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Sample records for sublexical sense ambiguity

  1. Sublexical Ambiguity Effect in Reading Chinese Disyllabic Compounds

    Science.gov (United States)

    Huang, Hsu-Wen; Lee, Chia-Ying; Tsai, Jie-Li; Tzeng, Ovid J.-L.

    2011-01-01

    For Chinese compounds, neighbors can share either both orthographic forms and meanings, or orthographic forms only. In this study, central presentation and visual half-field (VF) presentation methods were used in conjunction with ERP measures to investigate how readers solve the sublexical semantic ambiguity of the first constituent character in…

  2. The Lexicographic Treatment of Sublexical and Multilexical Lexical ...

    African Journals Online (AJOL)

    Information Technology

    Abstract: Dictionaries have in the past used a word-based approach in which sublexical and multilexical items were not regarded as lemmata. Metalexicography as the theoretical component of lexicography requires that sublexical and multilexical items be lemmatized and treated as inde- pendent lemmata in the ...

  3. Ambiguity of Quality in Remote Sensing Data

    Science.gov (United States)

    Lynnes, Christopher; Leptoukh, Greg

    2010-01-01

    This slide presentation reviews some of the issues in quality of remote sensing data. Data "quality" is used in several different contexts in remote sensing data, with quite different meanings. At the pixel level, quality typically refers to a quality control process exercised by the processing algorithm, not an explicit declaration of accuracy or precision. File level quality is usually a statistical summary of the pixel-level quality but is of doubtful use for scenes covering large areal extents. Quality at the dataset or product level, on the other hand, usually refers to how accurately the dataset is believed to represent the physical quantities it purports to measure. This assessment often bears but an indirect relationship at best to pixel level quality. In addition to ambiguity at different levels of granularity, ambiguity is endemic within levels. Pixel-level quality terms vary widely, as do recommendations for use of these flags. At the dataset/product level, quality for low-resolution gridded products is often extrapolated from validation campaigns using high spatial resolution swath data, a suspect practice at best. Making use of quality at all levels is complicated by the dependence on application needs. We will present examples of the various meanings of quality in remote sensing data and possible ways forward toward a more unified and usable quality framework.

  4. Implicit Sublexical Phonological Processing in an Acquired Dyslexic Patient.

    Science.gov (United States)

    Hildebrandt, Nancy; Sokol, Scott M.

    1993-01-01

    Reports a case study of an acquired dyslexic subject who showed no evidence of having any access to sublexical phonological information. Notes, however, that the subject showed normal effects of spelling regularity for low-frequency words, suggesting sublexical phonological processing. Suggests that the types of explicit tasks previously used are…

  5. Micro-Doppler Ambiguity Resolution Based on Short-Time Compressed Sensing

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    Jing-bo Zhuang

    2015-01-01

    Full Text Available When using a long range radar (LRR to track a target with micromotion, the micro-Doppler embodied in the radar echoes may suffer from ambiguity problem. In this paper, we propose a novel method based on compressed sensing (CS to solve micro-Doppler ambiguity. According to the RIP requirement, a sparse probing pulse train with its transmitting time random is designed. After matched filtering, the slow-time echo signals of the micromotion target can be viewed as randomly sparse sampling of Doppler spectrum. Select several successive pulses to form a short-time window and the CS sensing matrix can be built according to the time stamps of these pulses. Then performing Orthogonal Matching Pursuit (OMP, the unambiguous micro-Doppler spectrum can be obtained. The proposed algorithm is verified using the echo signals generated according to the theoretical model and the signals with micro-Doppler signature produced using the commercial electromagnetic simulation software FEKO.

  6. The influence of sense-contingent argument structure frequencies on ambiguity resolution in aphasia.

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    Huck, Anneline; Thompson, Robin L; Cruice, Madeline; Marshall, Jane

    2017-06-01

    Verbs with multiple senses can show varying argument structure frequencies, depending on the underlying sense. When acknowledge is used to mean 'recognise', it takes a direct object (DO), but when it is used to mean 'admit' it prefers a sentence complement (SC). The purpose of this study was to investigate whether people with aphasia (PWA) can exploit such meaning-structure probabilities during the reading of temporarily ambiguous sentences, as demonstrated for neurologically healthy individuals (NHI) in a self-paced reading study (Hare et al., 2003). Eleven people with mild or moderate aphasia and eleven neurologically healthy control participants read sentences while their eyes were tracked. Using adapted materials from the study by Hare et al. target sentences containing an SC structure (e.g. He acknowledged (that) his friends would probably help him a lot) were presented following a context prime that biased either a direct object (DO-bias) or sentence complement (SC-bias) reading of the verbs. Half of the stimuli sentences did not contain that so made the post verbal noun phrase (his friends) structurally ambiguous. Both groups of participants were influenced by structural ambiguity as well as by the context bias, indicating that PWA can, like NHI, use their knowledge of a verb's sense-based argument structure frequency during online sentence reading. However, the individuals with aphasia showed delayed reading patterns and some individual differences in their sensitivity to context and ambiguity cues. These differences compared to the NHI may contribute to difficulties in sentence comprehension in aphasia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Integration of lexical and sublexical processing in the spelling of regular words: a multiple single-case study in Italian dysgraphic patients.

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    Laiacona, Marcella; Capitani, Erminio; Zonca, Giusy; Scola, Ilaria; Saletta, Paola; Luzzatti, Claudio

    2009-01-01

    In this study we investigated 12 cases of "mixed dysgraphia", a spelling impairment where regular words are spelt better than either ambiguous words or regular non-words. Two explanations of mixed dysgraphia were formerly offered by Luzzatti et al. (1998): (i) a double functional lesion of the orthographic output lexicon (or damage to its access) and of the acoustic-to-phonological conversion; and (ii) some kind of interaction/summation between lexical and sublexical spelling routes when processing regular words. We first analysed whether a double functional lesion was sufficient to explain the mixed dysgraphia, checking acoustic-to-phonological conversion by means of the repetition of words and non-words: the answer was positive in five cases and uncertain in three. We tested the remaining four cases to see if there was an interaction between lexical and sublexical processing of regular words, quantifying for each patient, on a probabilistic basis, the separate contribution of the residual lexical and sublexical resources. We investigated whether the processing along these routes was simultaneous but independent ("independent cooperation") or if instead there was "interaction", i.e., the simultaneous activity led to an added increase of efficiency over and above the mere combination of separate success probabilities. For one case the processing along the two routes was independent, in the other three cases an interaction resulted. Following the same approach, we found that for the five cases with a double functional lesion, the observed success on regular word spelling was higher than that expected on a probabilistic basis, but the interpretation of this finding was different.

  8. Orthographic units in the absence of visual processing: Evidence from sublexical structure in braille.

    Science.gov (United States)

    Fischer-Baum, Simon; Englebretson, Robert

    2016-08-01

    Reading relies on the recognition of units larger than single letters and smaller than whole words. Previous research has linked sublexical structures in reading to properties of the visual system, specifically on the parallel processing of letters that the visual system enables. But whether the visual system is essential for this to happen, or whether the recognition of sublexical structures may emerge by other means, is an open question. To address this question, we investigate braille, a writing system that relies exclusively on the tactile rather than the visual modality. We provide experimental evidence demonstrating that adult readers of (English) braille are sensitive to sublexical units. Contrary to prior assumptions in the braille research literature, we find strong evidence that braille readers do indeed access sublexical structure, namely the processing of multi-cell contractions as single orthographic units and the recognition of morphemes within morphologically-complex words. Therefore, we conclude that the recognition of sublexical structure is not exclusively tied to the visual system. However, our findings also suggest that there are aspects of morphological processing on which braille and print readers differ, and that these differences may, crucially, be related to reading using the tactile rather than the visual sensory modality. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Neural correlates reveal sub-lexical orthography and phonology during reading aloud: A review

    Directory of Open Access Journals (Sweden)

    Kalinka eTimmer

    2014-08-01

    Full Text Available The sub-lexical conversion of graphemes-to-phonemes (GPC during reading has been investigated extensively with behavioral measures, as well as event-related potentials (ERPs. Most research utilizes silent reading (e.g., lexical decision task for which phonological activation is not a necessity. However, recent research employed reading aloud to capture sub-lexical GPC. The masked priming paradigm avoids strategic processing and is therefore well suitable for capturing sub-lexical processing instead of lexical effects. By employing ERPs, the on-line time course of sub-lexical GPC can be observed before the overt response. ERPs have revealed that besides phonological activation, as revealed by behavioral studies, there is also early orthographic activation. This review describes studies in one’s native language, in one’s second language, and in a cross-language situation. We discuss the implications the ERP results have on different (computational models. First, the ERP results show that computational models should assume an early locus of the grapheme-to-phoneme-conversion (GPC. Second, cross-language studies reveal that the phonological representations from both languages of a bilingual become activated automatically and the phonology belonging to the context is selected rapidly. Therefore, it is important to extend the scope of computational models of reading (aloud to multiple lexicons.

  10. Neural substrates of sublexical processing for spelling.

    Science.gov (United States)

    DeMarco, Andrew T; Wilson, Stephen M; Rising, Kindle; Rapcsak, Steven Z; Beeson, Pélagie M

    2017-01-01

    We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Treatment decisions under ambiguity.

    Science.gov (United States)

    Berger, Loïc; Bleichrodt, Han; Eeckhoudt, Louis

    2013-05-01

    Many health risks are ambiguous in the sense that reliable and credible information about these risks is unavailable. In health economics, ambiguity is usually handled through sensitivity analysis, which implicitly assumes that people are neutral towards ambiguity. However, empirical evidence suggests that people are averse to ambiguity and react strongly to it. This paper studies the effects of ambiguity aversion on two classical medical decision problems. If there is ambiguity regarding the diagnosis of a patient, ambiguity aversion increases the decision maker's propensity to opt for treatment. On the other hand, in the case of ambiguity regarding the effects of treatment, ambiguity aversion leads to a reduction in the propensity to choose treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Lexical and sublexical units in speech perception.

    Science.gov (United States)

    Giroux, Ibrahima; Rey, Arnaud

    2009-03-01

    Saffran, Newport, and Aslin (1996a) found that human infants are sensitive to statistical regularities corresponding to lexical units when hearing an artificial spoken language. Two sorts of segmentation strategies have been proposed to account for this early word-segmentation ability: bracketing strategies, in which infants are assumed to insert boundaries into continuous speech, and clustering strategies, in which infants are assumed to group certain speech sequences together into units (Swingley, 2005). In the present study, we test the predictions of two computational models instantiating each of these strategies i.e., Serial Recurrent Networks: Elman, 1990; and Parser: Perruchet & Vinter, 1998 in an experiment where we compare the lexical and sublexical recognition performance of adults after hearing 2 or 10 min of an artificial spoken language. The results are consistent with Parser's predictions and the clustering approach, showing that performance on words is better than performance on part-words only after 10 min. This result suggests that word segmentation abilities are not merely due to stronger associations between sublexical units but to the emergence of stronger lexical representations during the development of speech perception processes. Copyright © 2009, Cognitive Science Society, Inc.

  13. Ontology: ambiguity and accuracy

    Directory of Open Access Journals (Sweden)

    Marcelo Schiessl

    2012-08-01

    Full Text Available Ambiguity is a major obstacle to information retrieval. It is source of several researches in Information Science. Ontologies have been studied in order to solve problems related to ambiguities. Paradoxically, “ontology” term is also ambiguous and it is understood according to the use by the community. Philosophy and Computer Science seems to have the most accentuated difference related to the term sense. The former holds undisputed tradition and authority. The latter, in despite of being quite recent, holds an informal sense, but pragmatic. Information Science acts ranging from philosophical to computational approaches so as to get organized collections based on balance between users’ necessities and available information. The semantic web requires informational cycle automation and demands studies related to ontologies. Consequently, revisiting relevant approaches for the study of ontologies plays a relevant role as a way to provide useful ideas to researchers maintaining philosophical rigor, and convenience provided by computers.

  14. Evidence for the Modulation of Sub-Lexical Processing in Go No-Go Naming: The Elimination of the Frequency x Regularity Interaction

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    Cummine, Jacqueline; Amyotte, Josee; Pancheshen, Brent; Chouinard, Brea

    2011-01-01

    The Frequency (high vs. low) x Regularity (regular vs. exception) interaction found on naming response times is often taken as evidence for parallel processing of sub-lexical and lexical systems. Using a Go/No-go naming task, we investigated the effect of nonword versus pseudohomophone foils on sub-lexical processing and the subsequent Frequency x…

  15. Determinants of translation ambiguity

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    Degani, Tamar; Prior, Anat; Eddington, Chelsea M.; Arêas da Luz Fontes, Ana B.; Tokowicz, Natasha

    2016-01-01

    Ambiguity in translation is highly prevalent, and has consequences for second-language learning and for bilingual lexical processing. To better understand this phenomenon, the current study compared the determinants of translation ambiguity across four sets of translation norms from English to Spanish, Dutch, German and Hebrew. The number of translations an English word received was correlated across these different languages, and was also correlated with the number of senses the word has in English, demonstrating that translation ambiguity is partially determined by within-language semantic ambiguity. For semantically-ambiguous English words, the probability of the different translations in Spanish and Hebrew was predicted by the meaning-dominance structure in English, beyond the influence of other lexical and semantic factors, for bilinguals translating from their L1, and translating from their L2. These findings are consistent with models postulating direct access to meaning from L2 words for moderately-proficient bilinguals. PMID:27882188

  16. A sublexical training study for spelling in a biliterate Greek- and English-speaking child.

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    Niolaki, Georgia Z; Terzopoulos, Aris R; Masterson, Jackie

    2017-06-01

    RI is an emergent trilingual boy, literate in Greek and English, with difficulties in reading and spelling in both languages. Assessment with non-literacy tests revealed a deficit in phonological ability and in visual memory for sequentially presented characters. RI took part in a training programme that targeted sublexical spelling processes. Post-intervention assessment revealed improvement in reading and spelling in Greek but not in English. Assessments of lexical and sublexical skills showed improvement in nonword spelling and nonword reading for Greek. For English, there was some indication of improvement in nonword reading at delayed post-intervention testing, but no evidence of improvement in nonword spelling. Possible reasons for the difference in outcome for the two languages are considered, including the level of transparency of written Greek and English.

  17. Resolving the ambiguity: Making sense of intrinsic disorder when PDB structures disagree.

    Science.gov (United States)

    DeForte, Shelly; Uversky, Vladimir N

    2016-03-01

    Missing regions in X-ray crystal structures in the Protein Data Bank (PDB) have played a foundational role in the study of intrinsically disordered protein regions (IDPRs), especially in the development of in silico predictors of intrinsic disorder. However, a missing region is only a weak indication of intrinsic disorder, and this uncertainty is compounded by the presence of ambiguous regions, where more than one structure of the same protein sequence "disagrees" in terms of the presence or absence of missing residues. The question is this: are these ambiguous regions intrinsically disordered, or are they the result of static disorder that arises from experimental conditions, ensembles of structures, or domain wobbling? A novel way of looking at ambiguous regions in terms of the pattern between multiple PDB structures has been demonstrated. It was found that the propensity for intrinsic disorder increases as the level of ambiguity decreases. However, it is also shown that ambiguity is more likely to occur as the protein region is placed within different environmental conditions, and even the most ambiguous regions as a set display compositional bias that suggests flexibility. The results suggested that ambiguity is a natural result for many IDPRs crystallized under different conditions and that static disorder and wobbling domains are relatively rare. Instead, it is more likely that ambiguity arises because many of these regions were conditionally or partially disordered. © 2016 The Protein Society.

  18. Investigating the Prospective Sense of Agency: Effects of Processing Fluency, Stimulus Ambiguity, and Response Conflict

    Science.gov (United States)

    Sidarus, Nura; Vuorre, Matti; Metcalfe, Janet; Haggard, Patrick

    2017-01-01

    How do we know how much control we have over our environment? The sense of agency refers to the feeling that we are in control of our actions, and that, through them, we can control our external environment. Thus, agency clearly involves matching intentions, actions, and outcomes. The present studies investigated the possibility that processes of action selection, i.e., choosing what action to make, contribute to the sense of agency. Since selection of action necessarily precedes execution of action, such effects must be prospective. In contrast, most literature on sense of agency has focussed on the retrospective computation whether an outcome fits the action performed or intended. This hypothesis was tested in an ecologically rich, dynamic task based on a computer game. Across three experiments, we manipulated three different aspects of action selection processing: visual processing fluency, categorization ambiguity, and response conflict. Additionally, we measured the relative contributions of prospective, action selection-based cues, and retrospective, outcome-based cues to the sense of agency. Manipulations of action selection were orthogonally combined with discrepancy of visual feedback of action. Fluency of action selection had a small but reliable effect on the sense of agency. Additionally, as expected, sense of agency was strongly reduced when visual feedback was discrepant with the action performed. The effects of discrepant feedback were larger than the effects of action selection fluency, and sometimes suppressed them. The sense of agency is highly sensitive to disruptions of action-outcome relations. However, when motor control is successful, and action-outcome relations are as predicted, fluency or dysfluency of action selection provides an important prospective cue to the sense of agency. PMID:28450839

  19. The effect of the position of atypical character-to-sound correspondences on reading kanji words aloud: Evidence for a sublexical serially operating kanji reading process.

    Science.gov (United States)

    Sambai, Ami; Coltheart, Max; Uno, Akira

    2018-04-01

    In English, the size of the regularity effect on word reading-aloud latency decreases across position of irregularity. This has been explained by a sublexical serially operating reading mechanism. It is unclear whether sublexical serial processing occurs in reading two-character kanji words aloud. To investigate this issue, we studied how the position of atypical character-to-sound correspondences influenced reading performance. When participants read inconsistent-atypical words aloud mixed randomly with nonwords, reading latencies of words with an inconsistent-atypical correspondence in the initial position were significantly longer than words with an inconsistent-atypical correspondence in the second position. The significant difference of reading latencies for inconsistent-atypical words disappeared when inconsistent-atypical words were presented without nonwords. Moreover, reading latencies for words with an inconsistent-atypical correspondence in the first position were shorter than for words with a typical correspondence in the first position. This typicality effect was absent when the atypicality was in the second position. These position-of-atypicality effects suggest that sublexical processing of kanji occurs serially and that the phonology of two-character kanji words is generated from both a lexical parallel process and a sublexical serial process.

  20. Ambiguity Within Nursing Practice: An Evolutionary Concept Analysis.

    Science.gov (United States)

    McMahon, Michelle A; Dluhy, Nancy M

    2017-02-01

    To analyze the concept of ambiguity in a nursing context. Ambiguity is inherent within nursing practice. As health care becomes increasingly complex, nurses must continue to successfully deal with greater amounts of clinical ambiguity. Although ambiguity is discussed in nursing, minimal concept refinement exists to capture the contextual intricacies from a nursing lens. Nurse perception of an ambiguous clinical event, in combination with nurse tolerance level for ambiguity, can impact nurse response. Yet, little is known about what constitutes ambiguity within nursing practice (AWNP). Rodgers evolutionary method was used to explore AWNP, with emphasis on nurse thinking during ambiguous clinical situations. Literature searches across multiple databases yielded 38 articles for analysis. Attributes of AWNP include (a) variations in cues/available information, (b) multiple interpretations, (c) novel/nonroutine presentations, and (d) unpredictable. Antecedents include (a) a context-specific, clinical situation with ambiguous features needing evaluation and (b) an individual to sense a knowledge gap or perceive ambiguity. Consequences include ranges of (a) emotional, (b) behavioral, and (c) cognitive clinician responses. Preliminary findings support AWNP as a distinct concept in which ambiguity perceived by the nurse likely affects judgment, decision making, and clinical interventions. AWNP is a clinically relevant concept requiring continued development.

  1. The Lexicographic Treatment of Sublexical and Multilexical Items in a Northern Sotho Monolingual Dictionary: A Challenge for Lexicographers

    Directory of Open Access Journals (Sweden)

    Motlokwe Clifford Mphahlele

    2011-10-01

    Full Text Available

    Abstract: Dictionaries have in the past used a word-based approach in which sublexical and multilexical items were not regarded as lemmata. Metalexicography as the theoretical component of lexicography requires that sublexical and multilexical items be lemmatized and treated as independent lemmata in the macrostructure of dictionaries. One of the greater challenges for compiling a better and user-oriented Northern Sotho monolingual dictionary is to treat sublexical and multi-lexical items as macrostructural elements. Treating these items, the lexicographer faces quite a number of challenges. This article proposes possible ways in which sublexical and multilexical elements could be successfully treated in a Northern Sotho monolingual dictionary. Taking stock of these challenges, the writer comes with suggestions that would assist lexicographers in the compi-lation of a user-friendly, lexicon-based monolingual dictionary that would lead users to successful information retrieval.

    Keywords: SUBLEXICAL ITEMS, MULTILEXICAL ITEMS, AFFIXES, PREFIXAL MOR-PHEMES, SUFFIXAL MORPHEMES, INTEGRATED MICROSTRUCTURE, WORD-BASED APPROACH, LEMMATIZATION, COLLOCATIONS, COMPOUNDS, COMPLEXES, GROUP PREPOSITIONS, FIXED EXPRESSIONS, MORPHEMES, METALEXICOGRAPHICAL ASPECTS, WORD-FORMATION PROCESSES, WORD-INTERNAL FUNCTION, USER-ORIENTED MONO-LINGUAL DICTIONARY, GRAMMAR, HOMONYMOUS LEMMA, POLYSEMOUS LEMMA, DECODING, ENCODING, SEMANTIC COMMENT, SEMANTIC TRANSPARENCY

    Opsomming: Die leksikografiese behandeling van subleksikale en multi-leksikale items in 'n Noord-Sotho- eentalige woordeboek: 'n Uitdaging vir leksikograwe. Woordeboeke het in die verlede 'n woordgebaseerde benadering gevolg waar-by subleksikale en multileksikale items nie as lemmas beskou is nie. Die metaleksikografie as die teoretiese komponent van die leksikografie vereis dat subleksikale en multileksikale items gelem-matiseer word en as onafhanklike lemmas in die makrostuktuur van woordeboeke

  2. Resolving the range ambiguity in OFDR using digital signal processing

    International Nuclear Information System (INIS)

    Riesen, Nicolas; Lam, Timothy T-Y; Chow, Jong H

    2014-01-01

    A digitally range-gated variant of optical frequency domain reflectometry is demonstrated which overcomes the beat note ambiguity when sensing beyond a single frequency sweep. The range-gating is achieved using a spread spectrum technique involving time-stamping of the optical signal using high-frequency pseudorandom phase modulation. The reflections from different sections of fiber can then be isolated in the time domain by digitally inverting the phase modulation using appropriately-delayed copies of the pseudorandom noise code. Since the technique overcomes the range ambiguity in OFDR, it permits high sweep repetition rates without sacrificing range, thus allowing for high-bandwidth sensing over long lengths of fiber. This is demonstrated for the case of quasi-distributed sensing. (paper)

  3. Ambiguity

    DEFF Research Database (Denmark)

    Stein, Mari-Klara; Jensen, Tina Blegind

    Digitalization is changing the nature of work in knowledge professions in significant ways. One of the oft-observed, yet poorly understood, consequences of work digitalization in this context is increased ambiguity, frequently captured under the notion of blurred boundaries and paradoxes. While...... the introduction of ICTs is often credited with the potential to bring about ambiguity in a work context, we lack an in-depth understanding of how and why digitalization can introduce ambiguity, and what ambiguity actually means in this context. In this paper, we aim to further our current theorization...... of ambiguity in ICT-enabled work in knowledge professions. We offer a conceptual clarification of three related issues: (1) why does digitalization introduce ambiguity, (2) what kinds of ambiguities digitalization introduces, and (3) how workers act upon ambiguity....

  4. United we sense, divided we fail: context-driven perception of ambiguous visual stimuli.

    NARCIS (Netherlands)

    Klink, P.C.; van Wezel, R.J.A.; van Ee, R.

    2012-01-01

    Ambiguous visual stimuli provide the brain with sensory information that contains conflicting evidence for multiple mutually exclusive interpretations. Two distinct aspects of the phenomenological experience associated with viewing ambiguous visual stimuli are the apparent stability of perception

  5. United we sense, divided we fail: context-driven perception of ambiguous visual stimuli

    NARCIS (Netherlands)

    Klink, P. C; van Wezel, Richard Jack Anton; van Ee, R.

    2012-01-01

    Ambiguous visual stimuli provide the brain with sensory information that contains conflicting evidence for multiple mutually exclusive interpretations. Two distinct aspects of the phenomenological experience associated with viewing ambiguous visual stimuli are the apparent stability of perception

  6. Li Shangyin and the Art of Poetic Ambiguity

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    Maja Lavrač

    2016-12-01

    Full Text Available Li Shangyin (813–858, one of the most respected, mysterious, ambiguous and provocative of Chinese poets, lived during the late Tang period, when the glorious Tang dynasty was beginning to decline. It was a time of social riots, political division and painful general insecurity. Li Shangyin is famous as a highly original and committed poet who developed a unique style full of vague allusions and unusual images derived from the literary past (the traditional canon, myths and legends as well as from nature and personal experience. The second important feature of his poetry is a mysteriousness which finally leads to ambiguity. Ambiguity plays an essential role in most of his renowned poems, and he uses it to superbly connect present and past, reality and fantasy, and history and mythology. Thus, ambiguity and obscurity, respectively, often engender different interpretations among Chinese critics. These interpretations reflect the poems’ imaginative qualities, hypotheses and contradictions. Since each interpretive direction emphasizes but a single aspect of the poet’s character, it is more fitting to understand his ambiguous poems in symbolic terms. Such understanding entails that the meaning of the poem is not limited to one interpretation; rather, the poem’s poetic landscape opens itself up to various interpretations. Li Shangyin is actually most popular for his melancholic love poetry that reveals his ambiguous attitude to love. In this poetry, love is shrouded in a secret message. On the one hand, we can sense his moral disapproval of a secret but hopeless love; on the other, we can sense his passion. This leads to a paradox: the pleasing temptations of an illicit romance also exact a high price. In these love poems Li investigates various aspects of the worlds of passion which stoke in him feelings of rapture, satisfaction, joy and hope as well as feelings of doubt, frustration, despair and even thoughts of death.

  7. On the Relation between the General Affective Meaning and the Basic Sublexical, Lexical, and Inter-lexical Features of Poetic Texts-A Case Study Using 57 Poems of H. M. Enzensberger.

    Science.gov (United States)

    Ullrich, Susann; Aryani, Arash; Kraxenberger, Maria; Jacobs, Arthur M; Conrad, Markus

    2016-01-01

    The literary genre of poetry is inherently related to the expression and elicitation of emotion via both content and form. To explore the nature of this affective impact at an extremely basic textual level, we collected ratings on eight different general affective meaning scales-valence, arousal, friendliness, sadness, spitefulness, poeticity, onomatopoeia, and liking-for 57 German poems (" die verteidigung der wölfe ") which the contemporary author H. M. Enzensberger had labeled as either "friendly," "sad," or "spiteful." Following Jakobson's (1960) view on the vivid interplay of hierarchical text levels, we used multiple regression analyses to explore the specific influences of affective features from three different text levels (sublexical, lexical, and inter-lexical) on the perceived general affective meaning of the poems using three types of predictors: (1) Lexical predictor variables capturing the mean valence and arousal potential of words; (2) Inter-lexical predictors quantifying peaks, ranges, and dynamic changes within the lexical affective content; (3) Sublexical measures of basic affective tone according to sound-meaning correspondences at the sublexical level (see Aryani et al., 2016). We find the lexical predictors to account for a major amount of up to 50% of the variance in affective ratings. Moreover, inter-lexical and sublexical predictors account for a large portion of additional variance in the perceived general affective meaning . Together, the affective properties of all used textual features account for 43-70% of the variance in the affective ratings and still for 23-48% of the variance in the more abstract aesthetic ratings. In sum, our approach represents a novel method that successfully relates a prominent part of variance in perceived general affective meaning in this corpus of German poems to quantitative estimates of affective properties of textual components at the sublexical, lexical, and inter-lexical level.

  8. On the Relation between the General Affective Meaning and the Basic Sublexical, Lexical, and Inter-lexical Features of Poetic Texts—A Case Study Using 57 Poems of H. M. Enzensberger

    Science.gov (United States)

    Ullrich, Susann; Aryani, Arash; Kraxenberger, Maria; Jacobs, Arthur M.; Conrad, Markus

    2017-01-01

    The literary genre of poetry is inherently related to the expression and elicitation of emotion via both content and form. To explore the nature of this affective impact at an extremely basic textual level, we collected ratings on eight different general affective meaning scales—valence, arousal, friendliness, sadness, spitefulness, poeticity, onomatopoeia, and liking—for 57 German poems (“die verteidigung der wölfe”) which the contemporary author H. M. Enzensberger had labeled as either “friendly,” “sad,” or “spiteful.” Following Jakobson's (1960) view on the vivid interplay of hierarchical text levels, we used multiple regression analyses to explore the specific influences of affective features from three different text levels (sublexical, lexical, and inter-lexical) on the perceived general affective meaning of the poems using three types of predictors: (1) Lexical predictor variables capturing the mean valence and arousal potential of words; (2) Inter-lexical predictors quantifying peaks, ranges, and dynamic changes within the lexical affective content; (3) Sublexical measures of basic affective tone according to sound-meaning correspondences at the sublexical level (see Aryani et al., 2016). We find the lexical predictors to account for a major amount of up to 50% of the variance in affective ratings. Moreover, inter-lexical and sublexical predictors account for a large portion of additional variance in the perceived general affective meaning. Together, the affective properties of all used textual features account for 43–70% of the variance in the affective ratings and still for 23–48% of the variance in the more abstract aesthetic ratings. In sum, our approach represents a novel method that successfully relates a prominent part of variance in perceived general affective meaning in this corpus of German poems to quantitative estimates of affective properties of textual components at the sublexical, lexical, and inter-lexical level

  9. Ambiguity attitudes

    NARCIS (Netherlands)

    Trautmann, Stefan; van de Kuilen, Gijs; Keren, Gideon; Wu, George

    2015-01-01

    This chapter reviews the experimental literature on ambiguity attitudes, focusing on three topics. First, it considers various approaches to operationalize ambiguity in experiments. Second, the chapter reviews basic findings in the field regarding the prevalence of ambiguity aversion and ambiguity

  10. Are ambiguity aversion and ambiguity intolerance identical? A neuroeconomics investigation.

    Science.gov (United States)

    Tanaka, Yusuke; Fujino, Junya; Ideno, Takashi; Okubo, Shigetaka; Takemura, Kazuhisa; Miyata, Jun; Kawada, Ryosaku; Fujimoto, Shinsuke; Kubota, Manabu; Sasamoto, Akihiko; Hirose, Kimito; Takeuchi, Hideaki; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

    2014-01-01

    In recent years, there has been growing interest in understanding a person's reaction to ambiguous situations, and two similar constructs related to ambiguity, "ambiguity aversion" and "ambiguity intolerance," are defined in different disciplines. In the field of economic decision-making research, "ambiguity aversion" represents a preference for known risks relative to unknown risks. On the other hand, in clinical psychology, "ambiguity intolerance" describes the tendency to perceive ambiguous situations as undesirable. However, it remains unclear whether these two notions derived from different disciplines are identical or not. To clarify this issue, we combined an economic task, psychological questionnaires, and voxel-based morphometry (VBM) of structural brain magnetic resonance imaging (MRI) in a sample of healthy volunteers. The individual ambiguity aversion tendency parameter, as measured by our economic task, was negatively correlated with agreeableness scores on the self-reported version of the Revised NEO Personality Inventory. However, it was not correlated with scores of discomfort with ambiguity, one of the subscales of the Need for Closure Scale. Furthermore, the ambiguity aversion tendency parameter was negatively correlated with gray matter (GM) volume of areas in the lateral prefrontal cortex and parietal cortex, whereas ambiguity intolerance was not correlated with GM volume in any region. Our results suggest that ambiguity aversion, described in decision theory, may not necessarily be identical to ambiguity intolerance, referred to in clinical psychology. Cautious applications of decision theory to clinical neuropsychiatry are recommended.

  11. The effect of word length and other sublexical, lexical, and semantic variables on developmental reading deficits.

    Science.gov (United States)

    De Luca, Maria; Barca, Laura; Burani, Cristina; Zoccolotti, Pierluigi

    2008-12-01

    To examine the effect of word length and several sublexical, and lexico-semantic variables on the reading of Italian children with a developmental reading deficit. Previous studies indicated the role of word length in transparent orthographies. However, several factors that may interact with word length were not controlled for. Seventeen impaired and 34 skilled sixth-grade readers were presented words of different lengths, matched for initial phoneme, bigram frequency, word frequency, age of acquisition, and imageability. Participants were asked to read aloud, as quickly and as accurately as possible. Reaction times at the onset of pronunciation and mispronunciations were recorded. Impaired readers' reaction times indicated a marked effect of word length; in skilled readers, there was no length effect for short words but, rather, a monotonic increase from 6-letter words on. Regression analyses confirmed the role of word length and indicated the influence of word frequency (similar in impaired and skilled readers). No other variables predicted reading latencies. Word length differentially influenced word recognition in impaired versus skilled readers, irrespective of the action of (potentially interfering) sublexical, lexical, and semantic variables. It is proposed that the locus of the length effect is at a perceptual level of analysis. The independent influence of word frequency on the reading performance of both groups of participants indicates the sparing of lexical activation in impaired readers.

  12. Activation of semantic information at the sublexical level during handwriting production: Evidence from inhibition effects of Chinese semantic radicals in the picture-word interference paradigm.

    Science.gov (United States)

    Chen, Xuqian; Liao, Yuanlan; Chen, Xianzhe

    2017-08-01

    Using a non-alphabetic language (e.g., Chinese), the present study tested a novel view that semantic information at the sublexical level should be activated during handwriting production. Over 80% of Chinese characters are phonograms, in which semantic radicals represent category information (e.g., 'chair,' 'peach,' 'orange' are related to plants) while phonetic radicals represent phonetic information (e.g., 'wolf,' 'brightness,' 'male,' are all pronounced /lang/). Under different semantic category conditions at the lexical level (semantically related in Experiment 1; semantically unrelated in Experiment 2), the orthographic relatedness and semantic relatedness of semantic radicals in the picture name and its distractor were manipulated under different SOAs (i.e., stimulus onset asynchrony, the interval between the onset of the picture and the onset of the interference word). Two questions were addressed: (1) Is it possible that semantic information could be activated in the sublexical level conditions? (2) How are semantic and orthographic information dynamically accessed in word production? Results showed that both orthographic and semantic information were activated under the present picture-word interference paradigm, dynamically under different SOAs, which supported our view that discussions on semantic processes in the writing modality should be extended to the sublexical level. The current findings provide possibility for building new orthography-phonology-semantics models in writing. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  13. Children's Use of Gesture to Resolve Lexical Ambiguity

    Science.gov (United States)

    Kidd, Evan; Holler, Judith

    2009-01-01

    We report on a study investigating 3-5-year-old children's use of gesture to resolve lexical ambiguity. Children were told three short stories that contained two homonym senses; for example, "bat" (flying mammal) and "bat" (sports equipment). They were then asked to re-tell these stories to a second experimenter. The data were coded for the means…

  14. Symbol in View of Ambiguity

    Directory of Open Access Journals (Sweden)

    Mohamad reza Yousefi

    2013-11-01

    complex world.In general, in Persian poetry there are three types ofambiguity such as: uncertainty ambiguity, intentional and unintentional ambiguity.an effective literary texts, owes its origin to create multiple meanings and its levels of meaning. One serious differences literary work with other linguistic works is the plurality of meaning. Richness and depth range of literary texts and the creation of range meaning, in fact is ambiguity and uncertain.In this respect, by engaging the reader in creating meaning will be typicalinteraction between the audience and the text. Ambiguityprovidesopportunities for deep thinking and reacting of reader, so takes reader tobeyond Freedom of the text within its borders and freedom of thought has to be brought for its reader.   Having interaction betweentext and reader in the history has caused to different reactions and multiple conversations with generationswhich interpreted as dynamicliterary ofthe work. The ambiguity of the poem is creating by the symbols and symbolism.So the symbol isrhetorical element in addition to the apparentrealmeaning, suggests wide range of meaningto the reader.in classical Persian works ambiguity in text created differently such az:Allegory and metaphor and password which today symbolize are burdeningthis task .  In past Allegory in terms of clarity divided to the four categories:Implicitly, hint, password and widening.And allegories are codes allusions are hidden in them, so password knows asa symbol or a word that needed to understand. Metaphors are also due to the ambiguous, uncertain sense, to support new meaning to the traditional means in the appearance of metaphors (ie not considered true and apparentmeaning, but bymultiplevirtual semantics takesreadersto border suspicion of symbols.And generally are divided into two categories: metaphors that are close to the symbol and symbols that have been decoded.Since the natureof symbol is fundamentally ambiguous and multiple causes dynamics literary work

  15. Image Ambiguity and Fluency

    Science.gov (United States)

    Jakesch, Martina; Leder, Helmut; Forster, Michael

    2013-01-01

    Ambiguity is often associated with negative affective responses, and enjoying ambiguity seems restricted to only a few situations, such as experiencing art. Nevertheless, theories of judgment formation, especially the “processing fluency account”, suggest that easy-to-process (non-ambiguous) stimuli are processed faster and are therefore preferred to (ambiguous) stimuli, which are hard to process. In a series of six experiments, we investigated these contrasting approaches by manipulating fluency (presentation duration: 10ms, 50ms, 100ms, 500ms, 1000ms) and testing effects of ambiguity (ambiguous versus non-ambiguous pictures of paintings) on classification performance (Part A; speed and accuracy) and aesthetic appreciation (Part B; liking and interest). As indicated by signal detection analyses, classification accuracy increased with presentation duration (Exp. 1a), but we found no effects of ambiguity on classification speed (Exp. 1b). Fifty percent of the participants were able to successfully classify ambiguous content at a presentation duration of 100 ms, and at 500ms even 75% performed above chance level. Ambiguous artworks were found more interesting (in conditions 50ms to 1000ms) and were preferred over non-ambiguous stimuli at 500ms and 1000ms (Exp. 2a - 2c, 3). Importantly, ambiguous images were nonetheless rated significantly harder to process as non-ambiguous images. These results suggest that ambiguity is an essential ingredient in art appreciation even though or maybe because it is harder to process. PMID:24040172

  16. Measuring higher order ambiguity preferences.

    Science.gov (United States)

    Baillon, Aurélien; Schlesinger, Harris; van de Kuilen, Gijs

    2018-01-01

    We report the results from an experiment designed to measure attitudes towards ambiguity beyond ambiguity aversion. In particular, we implement recently-proposed model-free preference conditions of ambiguity prudence and ambiguity temperance. Ambiguity prudence has been shown to play an important role in precautionary behavior and the mere presence of ambiguity averse agents in markets. We observe that the majority of individuals' decisions are consistent with ambiguity aversion, ambiguity prudence and ambiguity temperance. This finding confirms the prediction of many popular (specifications of) ambiguity models and has important implications for models of prevention behavior.

  17. Risk, ambiguity and sovereign rating

    OpenAIRE

    Di Caro, Paolo

    2014-01-01

    Decisions of investing in sovereign assets involve both risk and ambiguity. Ambiguity arises from unknown elements characterizing the value of a generic sovereign. In presence of ambiguity, ambiguity-averse investors are prone to pay for obtaining summary information such as ratings which reduces ambiguity. Ambiguity-neutral and ambiguity-averse investors, then, make decisions on the basis of different informative sources. By presenting a simple model of sovereign rating under ambiguity, thre...

  18. Risk, ambiguity, and diversification

    OpenAIRE

    Sautua, Santiago-Ignacio

    2016-01-01

    Attitudes toward risk influence the decision to diversify among uncertain options. Yet, because in most situations the options are ambiguous, attitudes toward ambiguity may also play an important role. I conduct a laboratory experiment to investigate the effect of ambiguity on the decision to diversify. I find that diversification is more prevalent and more persistent under ambiguity than under risk. Moreover, excess diversification under ambiguity is driven by participants who stick with a s...

  19. Symbol in Point View of Ambiguity

    Directory of Open Access Journals (Sweden)

    Dr. M. R. Yousefi

    .In general, in Persian poetry there are three types ofambiguity such as: uncertainty ambiguity, intentional and unintentional ambiguity.an effective literary texts, owes its origin to create multiple meanings and its levels of meaning. One serious differences literary work with other linguistic works is the plurality of meaning. Richness and depth range of literary texts and the creation of range meaning, in fact is ambiguity and uncertain.In this respect, by engaging the reader in creating meaning will be typicalinteraction between the audience and the text. Ambiguityprovidesopportunities for deep thinking and reacting of reader, so takes reader tobeyond Freedom of the text within its borders and freedom of thought has to be brought for its reader. Having interaction betweentext and reader in the history has caused to different reactions and multiple conversations with generationswhich interpreted as dynamicliterary ofthe work. The ambiguity of the poem is creating by the symbols and symbolism.So the symbol isrhetorical element in addition to the apparentrealmeaning, suggests wide range of meaningto the reader.in classical Persian works ambiguity in text created differently such az:Allegory and metaphor and password ;which today symbolize are burdeningthis task .In past Allegory in terms of clarity divided to the four categories:Implicitly, hint, password and widening.And allegories are codes allusions are hidden in them, so password knows asa symbol or a word that needed to understand. Metaphors are also due to the ambiguous, uncertain sense, to support new meaning to the traditional means in the appearance of metaphors (ie not considered true and apparentmeaning, but bymultiplevirtual semantics takesreadersto border suspicion of symbols.And generally are divided into two categories: metaphors that are close to the symbol and symbols that have been decoded.Since the natureof symbol is fundamentally ambiguous and multiple causes dynamics literary work, poetry - especially

  20. Measuring higher order ambiguity preferences

    NARCIS (Netherlands)

    A. Baillon (Aurélien); Schlesinger, H. (Harris); G. van de Kuilen (Gijs)

    2017-01-01

    textabstractWe report the results from an experiment designed to measure attitudes towards ambiguity beyond ambiguity aversion. In particular, we implement recently-proposed model-free preference conditions of ambiguity prudence and ambiguity temperance. Ambiguity prudence has been shown to play an

  1. Phase-ambiguity resolution for QPSK modulation systems. Part 2: A method to resolve offset QPSK

    Science.gov (United States)

    Nguyen, Tien Manh

    1989-01-01

    Part 2 presents a new method to resolve the phase-ambiguity for Offset QPSK modulation systems. When an Offset Quaternary Phase-Shift-Keyed (OQPSK) communications link is utilized, the phase ambiguity of the reference carrier must be resolved. At the transmitter, two different unique words are separately modulated onto the quadrature carriers. At the receiver, the recovered carrier may have one of four possible phases, 0, 90, 180, or 270 degrees, referenced to the nominally correct phase. The IF portion of the channel may cause a phase-sense reversal, i.e., a reversal in the direction of phase rotation for a specified bit pattern. Hence, eight possible phase relationships (the so-called eight ambiguous phase conditions) between input and output of the demodulator must be resolved. Using the In-phase (I)/Quadrature (Q) channel reversal correcting property of an OQPSK Costas loop with integrated symbol synchronization, four ambiguous phase conditions are eliminated. Thus, only four possible ambiguous phase conditions remain. The errors caused by the remaining ambiguous phase conditions can be corrected by monitoring and detecting the polarity of the two unique words. The correction of the unique word polarities results in the complete phase-ambiguity resolution for the OQPSK system.

  2. Processing and Representation of Ambiguous Words in Chinese Reading: Evidence from Eye Movements.

    Science.gov (United States)

    Shen, Wei; Li, Xingshan

    2016-01-01

    In the current study, we used eye tracking to investigate whether senses of polysemous words and meanings of homonymous words are represented and processed similarly or differently in Chinese reading. Readers read sentences containing target words which was either homonymous words or polysemous words. The contexts of text preceding the target words were manipulated to bias the participants toward reading the ambiguous words according to their dominant, subordinate, or neutral meanings. Similarly, disambiguating regions following the target words were also manipulated to favor either the dominant or subordinate meanings of ambiguous words. The results showed that there were similar eye movement patterns when Chinese participants read sentences containing homonymous and polysemous words. The study also found that participants took longer to read the target word and the disambiguating text following it when the prior context and disambiguating regions favored divergent meanings rather than the same meaning. These results suggested that homonymy and polysemy are represented similarly in the mental lexicon when a particular meaning (sense) is fully specified by disambiguating information. Furthermore, multiple meanings (senses) are represented as separate entries in the mental lexicon.

  3. Ambiguous chair

    DEFF Research Database (Denmark)

    Manelius, Anne-Mette

    2011-01-01

    Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol.......Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol....

  4. The Ethics of Ambiguity

    Science.gov (United States)

    2016-01-01

    Understanding and embracing uncertainty are critical for effective teacher–learner relationships as well as for shared decision-making in the physician–patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity. PMID:28725771

  5. Exploring ambiguous realms

    DEFF Research Database (Denmark)

    Clemensen, Nana

    2016-01-01

    In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities in their intera...... in their interactions, testing social roles and conventions. This article explores the vigilance and creative agency displayed by Hang'ombe children, in an environment spurring their acquisition of distinct social and discursive skills.......In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities...

  6. SAR antenna design for ambiguity and multipath suppression

    DEFF Research Database (Denmark)

    Christensen, Erik Lintz; Dich, Mikael

    1993-01-01

    A high resolution airborne synthetic aperture radar (SAR) has been developed at the Electromagnetics Institute (EMI) for remote sensing applications. The paper considers the radiation of antennas for a SAR system from a systems perspective. The basic specifications of an idealised antenna...... are obtained from the required swath and the azimuth footprint needed for the SAR processing. The radiation from a real antenna causes unwanted signal returns that lead to intensity variations (multipath) and ghost echoes (ambiguity). Additional specifications are deduced by considering these signals...

  7. The Ethics of Ambiguity

    Directory of Open Access Journals (Sweden)

    Ronald E. Domen MD

    2016-06-01

    Full Text Available Understanding and embracing uncertainty are critical for effective teacher–learner relationships as well as for shared decision-making in the physician–patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity.

  8. Cooperative Learning, Responsibility, Ambiguity, Controversy and Support in Motivating Students

    Directory of Open Access Journals (Sweden)

    Ronald Brecke, PhD

    2007-08-01

    Full Text Available This paper argues that student motivation is nurtured more by intrinsic rather than extrinsic rewards. Rather than relying on grades alone to stimulate students, this paper explores how engendering a natural critical learning environment can give students a sense of ownership in their own learning and lead to their commitment to that learning. We examine uses of cooperative learning, shared responsibility, ambiguity, controversy and support in student motivation.

  9. Cooperative Learning, Responsibility, Ambiguity, Controversy and Support in Motivating Students

    Directory of Open Access Journals (Sweden)

    Ronald Brecke

    2007-01-01

    Full Text Available This paper argues that student motivation is nurtured more by intrinsic rather than extrinsic rewards. Rather than relying on grades alone to stimulate students, this paper explores how engendering a natural critical learning environment can give students a sense of ownership in their own learning and lead to their commitment to that learning. We examine uses of cooperative learning, shared responsibility, ambiguity, controversy and support in student motivation.

  10. Theory-Based Evaluation Meets Ambiguity

    DEFF Research Database (Denmark)

    Dahler-Larsen, Peter

    2017-01-01

    As theory-based evaluation (TBE) engages in situations where multiple stakeholders help develop complex program theory about dynamic phenomena in politically contested settings, it becomes difficult to develop and use program theory without ambiguity. The purpose of this article is to explore...... ambiguity as a fruitful perspective that helps TBE face current challenges. Literatures in organization theory and political theory are consulted in order to cultivate the concept of ambiguity. Janus variables (which work in two ways) and other ambiguous aspects of program theories are classified...... and exemplified. Stances towards ambiguity are considered, as are concrete steps that TBE evaluators can take to identify and deal with ambiguity in TBE....

  11. Ambiguity aversion in schizophrenia: An fMRI study of decision-making under risk and ambiguity.

    Science.gov (United States)

    Fujino, Junya; Hirose, Kimito; Tei, Shisei; Kawada, Ryosaku; Tsurumi, Kosuke; Matsukawa, Noriko; Miyata, Jun; Sugihara, Genichi; Yoshihara, Yujiro; Ideno, Takashi; Aso, Toshihiko; Takemura, Kazuhisa; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

    2016-12-01

    When making decisions in everyday life, we often have to choose between uncertain outcomes. Economic studies have demonstrated that healthy people tend to prefer options with known probabilities (risk) than those with unknown probabilities (ambiguity), which is referred to as "ambiguity aversion." However, it remains unclear how patients with schizophrenia behave under ambiguity, despite growing evidence of their altered decision-making under uncertainty. In this study, combining economic tools and functional magnetic resonance imaging (fMRI), we assessed the attitudes toward risk/ambiguity and investigated the neural correlates during decision-making under risk/ambiguity in schizophrenia. Although no significant difference in attitudes under risk was observed, patients with schizophrenia chose ambiguity significantly more often than the healthy controls. Attitudes under risk and ambiguity did not correlate across patients with schizophrenia. Furthermore, unlike in the healthy controls, activation of the left lateral orbitofrontal cortex was not increased during decision-making under ambiguity compared to under risk in schizophrenia. These results suggest that ambiguity aversion, a well-established subjective bias, is attenuated in patients with schizophrenia, highlighting the need to distinguish between risk and ambiguity when assessing decision-making under these situations. Our findings, comprising important clinical implications, contribute to improved understanding of the mechanisms underlying altered decision-making in patients with schizophrenia. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Writing nonsense: the interaction between lexical and sublexical knowledge in the priming of nonword spelling.

    Science.gov (United States)

    Martin, Daisy H; Barry, Christopher

    2012-08-01

    The task of spelling nonwords to dictation necessarily requires the operation of a sublexical or assembled sound-to-spelling conversion process. We report an experiment that shows a clear lexical priming effect on nonword spelling (e.g., /vi:m/ was spelled as VEME more often following the prime word "theme" and as VEAM more often following "dream"), which was larger for lexically low-probability (or low-contingency) than for common (or high-contingency) spellings. Priming diminished when an unrelated word intervened between the prime word and target nonword and did so more for the production of low- than for high-contingency spellings. We interpret these results within an interactive model of spelling production that proposes feedback from the graphemic level to both the lexical and assembled spelling processes.

  13. Ambiguity aversion in rhesus macaques

    Directory of Open Access Journals (Sweden)

    Benjamin eHayden

    2010-09-01

    Full Text Available People generally prefer risky options, which have fully specified outcome probabilities, to ambiguous options, which have unspecified probabilities. This preference, formalized in economics, is strong enough that people will reliably prefer a risky option to an ambiguous option with a greater expected value. Explanations for ambiguity aversion often invoke uniquely human faculties like language, self-justification, or a desire to avoid public embarrassment. Challenging these ideas, here we demonstrate that a preference for unambiguous options is shared with rhesus macaques. We trained four monkeys to choose between pairs of options that both offered explicitly cued probabilities of large and small juice outcomes. We then introduced occasional trials where one of the options was obscured and examined their resulting preferences; we ran humans in a parallel experiment on a nearly identical task. We found that monkeys reliably preferred risky options to ambiguous ones, even when this bias was costly, closely matching the behavior of humans in the analogous task. Notably, ambiguity aversion varied parametrically with the extent of ambiguity. As expected, ambiguity aversion gradually declined as monkeys learned the underlying probability distribution of rewards. These data indicate that ambiguity aversion reflects fundamental cognitive biases shared with other animals rather than uniquely human factors guiding decisions.

  14. Five-year-olds do not show ambiguity aversion in a risk and ambiguity task with physical objects.

    Science.gov (United States)

    Li, Rosa; Roberts, Rachel C; Huettel, Scott A; Brannon, Elizabeth M

    2017-07-01

    Ambiguity aversion arises when a decision maker prefers risky gambles with known probabilities over equivalent ambiguous gambles with unknown probabilities. This phenomenon has been consistently observed in adults across a large body of empirical work. Evaluating ambiguity aversion in young children, however, has posed methodological challenges because probabilistic representations appropriate for adults might not be understood by young children. Here, we established a novel method for representing risk and ambiguity with physical objects that overcomes previous methodological limitations and allows us to measure ambiguity aversion in young children. We found that individual 5-year-olds exhibited consistent choice preferences and, as a group, exhibited no ambiguity aversion in a task that evokes ambiguity aversion in adults. Across individuals, 5-year-olds exhibited greater variance in ambiguity preferences compared with adults tested under similar conditions. This suggests that ambiguity aversion is absent during early childhood and emerges over the course of development. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Ambiguity aversion is not universal

    NARCIS (Netherlands)

    Kocher, M.G.; Lahno, Amrei; Trautmann, Stefan

    Assuming universal ambiguity aversion, an extensive theoretical literature studies how ambiguity can account for market anomalies from the perspective of expected utility-based theories. We provide a systematic experimental assessment of ambiguity attitudes in different likelihood ranges, and in the

  16. Effective ambiguity checking in biosequence analysis

    Directory of Open Access Journals (Sweden)

    Giegerich Robert

    2005-06-01

    Full Text Available Abstract Background Ambiguity is a problem in biosequence analysis that arises in various analysis tasks solved via dynamic programming, and in particular, in the modeling of families of RNA secondary structures with stochastic context free grammars. Several types of analysis are invalidated by the presence of ambiguity. As this problem inherits undecidability (as we show here from the namely problem for context free languages, there is no complete algorithmic solution to the problem of ambiguity checking. Results We explain frequently observed sources of ambiguity, and show how to avoid them. We suggest four testing procedures that may help to detect ambiguity when present, including a just-in-time test that permits to work safely with a potentially ambiguous grammar. We introduce, for the special case of stochastic context free grammars and RNA structure modeling, an automated partial procedure for proving non-ambiguity. It is used to demonstrate non-ambiguity for several relevant grammars. Conclusion Our mechanical proof procedure and our testing methods provide a powerful arsenal of methods to ensure non-ambiguity.

  17. Vignettes of Ambiguity

    Science.gov (United States)

    Gotz, Ignacio L.

    2010-01-01

    This article is an exploration of ambiguity as it appears in various guises in philosophical, social, political, and educational situations. Among these situations is the experience of exile. The exploration is conducted by means of literary anecdotes and real-life instances, hence the use of vignettes. The suggestion is made that ambiguity can be…

  18. Properties of Ambiguity Functions

    OpenAIRE

    Mulcahy-Stanislawczyk, John

    2014-01-01

    The use of ambiguity functions in radar signal design and analysis is very common. Understanding the various properties and meanings of ambiguity functions allow a signal designer to understand the time delay and doppler shift properties of a given signal. Through the years, several different versions of the ambiguity function have been used. Each of these functions essentially have the same physical meaning; however, the use of different functions makes it difficult to be sure that certai...

  19. Lexical ambiguity resolution

    Energy Technology Data Exchange (ETDEWEB)

    Small, S.; Cottrell, G.; Tanenhaus, M.

    1987-01-01

    This book collects much of the best research currently available on the problem of lexical ambiguity resolution in the processing of human language. When taken out of context, sentences are usually ambiguous. When actually uttered in a dialogue or written in text, these same sentences often have unique interpretations. The inherent ambiguity of isolated sentences, becomes obvious in the attempt to write a computer program to understand them. Different views have emerged on the nature of context and the mechanisms by which it directs unambiguous understanding of words and sentences. These perspectives are represented and discussed. Eighteen original papers from a valuable source book for cognitive scientists in AI, psycholinguistics, neuropsychology, or theoretical linguistics.

  20. A Semantic Lexicon-Based Approach for Sense Disambiguation and Its WWW Application

    Science.gov (United States)

    di Lecce, Vincenzo; Calabrese, Marco; Soldo, Domenico

    This work proposes a basic framework for resolving sense disambiguation through the use of Semantic Lexicon, a machine readable dictionary managing both word senses and lexico-semantic relations. More specifically, polysemous ambiguity characterizing Web documents is discussed. The adopted Semantic Lexicon is WordNet, a lexical knowledge-base of English words widely adopted in many research studies referring to knowledge discovery. The proposed approach extends recent works on knowledge discovery by focusing on the sense disambiguation aspect. By exploiting the structure of WordNet database, lexico-semantic features are used to resolve the inherent sense ambiguity of written text with particular reference to HTML resources. The obtained results may be extended to generic hypertextual repositories as well. Experiments show that polysemy reduction can be used to hint about the meaning of specific senses in given contexts.

  1. Neural Mechanisms Underlying Risk and Ambiguity Attitudes.

    Science.gov (United States)

    Blankenstein, Neeltje E; Peper, Jiska S; Crone, Eveline A; van Duijvenvoorde, Anna C K

    2017-11-01

    Individual differences in attitudes to risk (a taste for risk, known probabilities) and ambiguity (a tolerance for uncertainty, unknown probabilities) differentially influence risky decision-making. However, it is not well understood whether risk and ambiguity are coded differently within individuals. Here, we tested whether individual differences in risk and ambiguity attitudes were reflected in distinct neural correlates during choice and outcome processing of risky and ambiguous gambles. To these ends, we developed a neuroimaging task in which participants ( n = 50) chose between a sure gain and a gamble, which was either risky or ambiguous, and presented decision outcomes (gains, no gains). From a separate task in which the amount, probability, and ambiguity level were varied, we estimated individuals' risk and ambiguity attitudes. Although there was pronounced neural overlap between risky and ambiguous gambling in a network typically related to decision-making under uncertainty, relatively more risk-seeking attitudes were associated with increased activation in valuation regions of the brain (medial and lateral OFC), whereas relatively more ambiguity-seeking attitudes were related to temporal cortex activation. In addition, although striatum activation was observed during reward processing irrespective of a prior risky or ambiguous gamble, reward processing after an ambiguous gamble resulted in enhanced dorsomedial PFC activation, possibly functioning as a general signal of uncertainty coding. These findings suggest that different neural mechanisms reflect individual differences in risk and ambiguity attitudes and that risk and ambiguity may impact overt risk-taking behavior in different ways.

  2. A storm is coming? Collective sensemaking and ambiguity in an inter-organizational team managing railway system disruptions

    NARCIS (Netherlands)

    Merkus, Sander; Willems, Thijs; Schipper, Danny; van Marrewijk, Alfons; Koppenjan, Joop; Veenswijk, Marcel; Bakker, H.L.M.

    2016-01-01

    This paper studies the ways in which members of inter-organizational teams collectively make sense of unexpected events and how they decide upon engaging in action. Frequently, ambiguity dominates such change processes aimed to create common understanding. Using the notion of the duality of

  3. WORD SENSE DISAMBIGUATION FOR TAMIL LANGUAGE USING PART-OF-SPEECH AND CLUSTERING TECHNIQUE

    Directory of Open Access Journals (Sweden)

    P. ISWARYA

    2017-09-01

    Full Text Available Word sense disambiguation is an important task in Natural Language Processing (NLP, and this paper concentrates on the problem of target word selection in machine translation. The proposed method called enhanced Word Sense Disambiguation with Part-of-Speech and Clustering based Sensecollocation (WSDPCS consists of two steps namely (i Part-of-Speech (POS tagger in disambiguating word senses and (ii Enhanced with Clustering and Sense-collocation dictionary based disambiguation. In the first step an ambiguous Tamil words are disambiguated using Tamil and English POS Tagger. If it has same type of POS category labels, then it passes the word to the next step. In the second step ambiguity is resolved using sense-collocation dictionary. The experimental analysis shows that the accuracy of proposed WSDPCS method achieves 1.86% improvement over an existing method.

  4. Sampling experience reverses preferences for ambiguity

    NARCIS (Netherlands)

    Ert, E.; Trautmann, S.T.

    People often need to choose between alternatives with known probabilities (risk) and alternatives with unknown probabilities (ambiguity). Such decisions are characterized by attitudes towards ambiguity, which are distinct from risk attitudes. Most studies of ambiguity attitudes have focused on the

  5. Ambiguity effects of rhyme and meter.

    Science.gov (United States)

    Wallot, Sebastian; Menninghaus, Winfried

    2018-04-23

    Previous research has shown that rhyme and meter-although enhancing prosodic processing ease and memorability-also tend to make semantic processing more demanding. Using a set of rhymed and metered proverbs, as well as nonrhymed and nonmetered versions of these proverbs, the present study reveals this hitherto unspecified difficulty of comprehension to be specifically driven by perceived ambiguity. Roman Jakobson was the 1st to propose this hypothesis, in 1960. He suggested that "ambiguity is an intrinsic, inalienable feature" of "parallelistic" diction of which the combination of rhyme and meter is a pronounced example. Our results show that ambiguity indeed explains a substantial portion of the rhyme- and meter-driven difficulty of comprehension. Longer word-reading times differentially reflected ratings for ambiguity and comprehension difficulty. However, the ambiguity effect is not "inalienable." Rather, many rhymed and metered sentences turned out to be low in ambiguity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  6. Phonological ambiguity modulates resolution of semantic ambiguity during reading: An fMRI study of Hebrew.

    Science.gov (United States)

    Bitan, Tali; Kaftory, Asaf; Meiri-Leib, Adi; Eviatar, Zohar; Peleg, Orna

    2017-10-01

    The current fMRI study examined the role of phonology in the extraction of meaning from print in each hemisphere by comparing homophonic and heterophonic homographs (ambiguous words in which both meanings have the same or different sounds respectively, e.g., bank or tear). The analysis distinguished between the first phase, in which participants read ambiguous words without context, and the second phase in which the context resolves the ambiguity. Native Hebrew readers were scanned during semantic relatedness judgments on pairs of words in which the first word was either a homophone or a heterophone and the second word was related to its dominant or subordinate meaning. In Phase 1 there was greater activation for heterophones in left inferior frontal gyrus (IFG), pars opercularis, and more activation for homophones in bilateral IFG pars orbitalis, suggesting that resolution of the conflict at the phonological level has abolished the semantic ambiguity for heterophones. Reduced activation for all ambiguous words in temporo-parietal regions suggests that although ambiguity enhances controlled lexical selection processes in frontal regions it reduces reliance on bottom-up mapping processes. After presentation of the context, a larger difference between the dominant and subordinate meaning was found for heterophones in all reading-related regions, suggesting a greater engagement for heterophones with the dominant meaning. Altogether these results are consistent with the prominent role of phonological processing in visual word recognition. Finally, despite differences in hemispheric asymmetry between homophones and heterophones, ambiguity resolution, even toward the subordinate meaning, is largely left lateralized. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. A Neural Signature Encoding Decisions under Perceptual Ambiguity.

    Science.gov (United States)

    Sun, Sai; Yu, Rongjun; Wang, Shuo

    2017-01-01

    People often make perceptual decisions with ambiguous information, but it remains unclear whether the brain has a common neural substrate that encodes various forms of perceptual ambiguity. Here, we used three types of perceptually ambiguous stimuli as well as task instructions to examine the neural basis for both stimulus-driven and task-driven perceptual ambiguity. We identified a neural signature, the late positive potential (LPP), that encoded a general form of stimulus-driven perceptual ambiguity. In addition to stimulus-driven ambiguity, the LPP was also modulated by ambiguity in task instructions. To further specify the functional role of the LPP and elucidate the relationship between stimulus ambiguity, behavioral response, and the LPP, we employed regression models and found that the LPP was specifically associated with response latency and confidence rating, suggesting that the LPP encoded decisions under perceptual ambiguity. Finally, direct behavioral ratings of stimulus and task ambiguity confirmed our neurophysiological findings, which could not be attributed to differences in eye movements either. Together, our findings argue for a common neural signature that encodes decisions under perceptual ambiguity but is subject to the modulation of task ambiguity. Our results represent an essential first step toward a complete neural understanding of human perceptual decision making.

  8. Defuzzification Strategies for Fuzzy Classifications of Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Peter Hofmann

    2016-06-01

    Full Text Available The classes in fuzzy classification schemes are defined as fuzzy sets, partitioning the feature space through fuzzy rules, defined by fuzzy membership functions. Applying fuzzy classification schemes in remote sensing allows each pixel or segment to be an incomplete member of more than one class simultaneously, i.e., one that does not fully meet all of the classification criteria for any one of the classes and is member of more than one class simultaneously. This can lead to fuzzy, ambiguous and uncertain class assignation, which is unacceptable for many applications, indicating the need for a reliable defuzzification method. Defuzzification in remote sensing has to date, been performed by “crisp-assigning” each fuzzy-classified pixel or segment to the class for which it best fulfills the fuzzy classification rules, regardless of its classification fuzziness, uncertainty or ambiguity (maximum method. The defuzzification of an uncertain or ambiguous fuzzy classification leads to a more or less reliable crisp classification. In this paper the most common parameters for expressing classification uncertainty, fuzziness and ambiguity are analysed and discussed in terms of their ability to express the reliability of a crisp classification. This is done by means of a typical practical example from Object Based Image Analysis (OBIA.

  9. Analyzing Ambiguity of Context-Free Grammars

    DEFF Research Database (Denmark)

    Brabrand, Claus; Giegerich, Robert; Møller, Anders

    2010-01-01

    It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. We...... observe that there is a simple linguistic characterization of the grammar ambiguity problem, and we show how to exploit this by presenting an ambiguity analysis framework based on conservative language approximations. As a concrete example, we propose a technique based on local regular approximations...

  10. Generative Learning: Adults Learning within Ambiguity

    Science.gov (United States)

    Nicolaides, Aliki

    2015-01-01

    This study explored the extent to which ambiguity can serve as a catalyst for adult learning. The purpose of this study is to understand learning that is generated when encountering ambiguity agitated by the complexity of liquid modernity. "Ambiguity," in this study, describes an encounter with an appearance of reality that is at first…

  11. Positive fEMG Patterns with Ambiguity in Paintings.

    Science.gov (United States)

    Jakesch, Martina; Goller, Juergen; Leder, Helmut

    2017-01-01

    Whereas ambiguity in everyday life is often negatively evaluated, it is considered key in art appreciation. In a facial EMG study, we tested whether the positive role of visual ambiguity in paintings is reflected in a continuous affective evaluation on a subtle level. We presented ambiguous (disfluent) and non-ambiguous (fluent) versions of Magritte paintings and found that M. Zygomaticus major activation was higher and M. corrugator supercilii activation was lower for ambiguous than for non-ambiguous versions. Our findings reflect a positive continuous affective evaluation to visual ambiguity in paintings over the 5 s presentation time. We claim that this finding is indirect evidence for the hypothesis that visual stimuli classified as art, evoke a safe state for indulging into experiencing ambiguity, challenging the notion that processing fluency is generally related to positive affect.

  12. Probability judgments under ambiguity and conflict.

    Science.gov (United States)

    Smithson, Michael

    2015-01-01

    Whether conflict and ambiguity are distinct kinds of uncertainty remains an open question, as does their joint impact on judgments of overall uncertainty. This paper reviews recent advances in our understanding of human judgment and decision making when both ambiguity and conflict are present, and presents two types of testable models of judgments under conflict and ambiguity. The first type concerns estimate-pooling to arrive at "best" probability estimates. The second type is models of subjective assessments of conflict and ambiguity. These models are developed for dealing with both described and experienced information. A framework for testing these models in the described-information setting is presented, including a reanalysis of a multi-nation data-set to test best-estimate models, and a study of participants' assessments of conflict, ambiguity, and overall uncertainty reported by Smithson (2013). A framework for research in the experienced-information setting is then developed, that differs substantially from extant paradigms in the literature. This framework yields new models of "best" estimates and perceived conflict. The paper concludes with specific suggestions for future research on judgment and decision making under conflict and ambiguity.

  13. Renormalon ambiguities in NRQCD operator matrix elements

    International Nuclear Information System (INIS)

    Bodwin, G.T.; Chen, Y.

    1999-01-01

    We analyze the renormalon ambiguities that appear in factorization formulas in QCD. Our analysis contains a simple argument that the ambiguities in the short-distance coefficients and operator matrix elements are artifacts of dimensional-regularization factorization schemes and are absent in cutoff schemes. We also present a method for computing the renormalon ambiguities in operator matrix elements and apply it to a computation of the ambiguities in the matrix elements that appear in the NRQCD factorization formulas for the annihilation decays of S-wave quarkonia. Our results, combined with those of Braaten and Chen for the short-distance coefficients, provide an explicit demonstration that the ambiguities cancel in the physical decay rates. In addition, we analyze the renormalon ambiguities in the Gremm-Kapustin relation and in various definitions of the heavy-quark mass. copyright 1999 The American Physical Society

  14. Neural Correlates of Decision-Making Under Ambiguity and Conflict.

    Science.gov (United States)

    Pushkarskaya, Helen; Smithson, Michael; Joseph, Jane E; Corbly, Christine; Levy, Ifat

    2015-01-01

    HIGHLIGHTS We use a simple gambles design in an fMRI study to compare two conditions: ambiguity and conflict.Participants were more conflict averse than ambiguity averse.Ambiguity aversion did not correlate with conflict aversion.Activation in the medial prefrontal cortex correlated with ambiguity level and ambiguity aversion.Activation in the ventral striatum correlated with conflict level and conflict aversion. Studies of decision making under uncertainty generally focus on imprecise information about outcome probabilities ("ambiguity"). It is not clear, however, whether conflicting information about outcome probabilities affects decision making in the same manner as ambiguity does. Here we combine functional magnetic resonance imaging (fMRI) and a simple gamble design to study this question. In this design the levels of ambiguity and conflict are parametrically varied, and ambiguity and conflict gambles are matched on expected value. Behaviorally, participants avoided conflict more than ambiguity, and attitudes toward ambiguity and conflict did not correlate across participants. Neurally, regional brain activation was differentially modulated by ambiguity level and aversion to ambiguity and by conflict level and aversion to conflict. Activation in the medial prefrontal cortex was correlated with the level of ambiguity and with ambiguity aversion, whereas activation in the ventral striatum was correlated with the level of conflict and with conflict aversion. These novel results indicate that decision makers process imprecise and conflicting information differently, a finding that has important implications for basic and clinical research.

  15. Reactive agents and perceptual ambiguity

    NARCIS (Netherlands)

    Dartel, M. van; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.; Herik, H.J. van den

    2005-01-01

    Reactive agents are generally believed to be incapable of coping with perceptual ambiguity (i.e., identical sensory states that require different responses). However, a recent finding suggests that reactive agents can cope with perceptual ambiguity in a simple model (Nolfi, 2002). This paper

  16. Alcohol reduces aversion to ambiguity

    Directory of Open Access Journals (Sweden)

    Tadeusz eTyszka

    2015-01-01

    Full Text Available Several years ago, Cohen, Dearnaley, and Hansel [1] demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly [2]. The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar, where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

  17. Alcohol reduces aversion to ambiguity.

    Science.gov (United States)

    Tyszka, Tadeusz; Macko, Anna; Stańczak, Maciej

    2014-01-01

    Several years ago, Cohen et al. (1958) demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly (Camerer and Weber, 1992). The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar), where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

  18. Word embeddings and recurrent neural networks based on Long-Short Term Memory nodes in supervised biomedical word sense disambiguation.

    Science.gov (United States)

    Jimeno Yepes, Antonio

    2017-09-01

    Word sense disambiguation helps identifying the proper sense of ambiguous words in text. With large terminologies such as the UMLS Metathesaurus ambiguities appear and highly effective disambiguation methods are required. Supervised learning algorithm methods are used as one of the approaches to perform disambiguation. Features extracted from the context of an ambiguous word are used to identify the proper sense of such a word. The type of features have an impact on machine learning methods, thus affect disambiguation performance. In this work, we have evaluated several types of features derived from the context of the ambiguous word and we have explored as well more global features derived from MEDLINE using word embeddings. Results show that word embeddings improve the performance of more traditional features and allow as well using recurrent neural network classifiers based on Long-Short Term Memory (LSTM) nodes. The combination of unigrams and word embeddings with an SVM sets a new state of the art performance with a macro accuracy of 95.97 in the MSH WSD data set. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Risk, Ambiguity, and Insurance.

    Science.gov (United States)

    1984-10-01

    California felt that once a severe earthquake occurs, it is le likely to occur in the near future (Kunreuther et al., 1978). When probabilities are...psychological model of how people assess probabilities In ambiguous circumstances. This model is based on three principles : (1) In assessing an ambiguous...TECHNICAL REPORTS DISTRIBUTION LIST 050 Department of the Navy CAPT Paul R. Chatelier Dr. Andrew Rachnitser Office of the Deputy Under Secretary Office of

  20. Recommendations for reducing ambiguity in written procedures.

    Energy Technology Data Exchange (ETDEWEB)

    Matzen, Laura E.

    2009-11-01

    Previous studies in the nuclear weapons complex have shown that ambiguous work instructions (WIs) and operating procedures (OPs) can lead to human error, which is a major cause for concern. This report outlines some of the sources of ambiguity in written English and describes three recommendations for reducing ambiguity in WIs and OPs. The recommendations are based on commonly used research techniques in the fields of linguistics and cognitive psychology. The first recommendation is to gather empirical data that can be used to improve the recommended word lists that are provided to technical writers. The second recommendation is to have a review in which new WIs and OPs and checked for ambiguities and clarity. The third recommendation is to use self-paced reading time studies to identify any remaining ambiguities before the new WIs and OPs are put into use. If these three steps are followed for new WIs and OPs, the likelihood of human errors related to ambiguity could be greatly reduced.

  1. The Ethics of Strategic Ambiguity.

    Science.gov (United States)

    Paul, Jim; Strbiak, Christy A.

    1997-01-01

    Examines the concept of strategic ambiguity in communication, and addresses the ethics of strategic ambiguity from an intrapersonal perspective that considers the congruity of communicators' espoused-ethics, ethics-in-use, and behavior, where ethical judgements are based on the congruity between espoused-ethics and actual behavior. Poses questions…

  2. Quantization ambiguity, ergodicity and semiclassics

    International Nuclear Information System (INIS)

    Kaplan, Lev

    2002-01-01

    It is well known that almost all eigenstates of a classically ergodic system are individually ergodic on coarse-grained scales. This has important implications for the quantization ambiguity in ergodic systems: the difference between alternative quantizations is suppressed compared with the O( h-bar 2 ) ambiguity in the integrable or regular case. For two-dimensional ergodic systems in the high-energy regime, individual eigenstates are independent of the choice of quantization procedure, in contrast with the regular case, where even the ordering of eigenlevels is ambiguous. Surprisingly, semiclassical methods are shown to be much more precise in any dimension for chaotic than for integrable systems

  3. What sense can the sense-making perspective make for economics?

    Science.gov (United States)

    Cortés, Mauricio; Londoño, Sandra

    2009-06-01

    A landscape of interdisciplinary decision theories is sketched with a tentative place for the sense-making approach presented by Salvatore et al (2009). Uncertainty and ambiguity are highlighted as key concepts in both, economics and sense-making perspectives aligning possible and useful conceptual coincidences among post Keynesian economics (Shackle 1974; Davidson 2005) cultural psychology (Salvatore et al. 2009) and organization theory (March 1978, 1994; Weick 1995). Few ideas for the construction of possible research agenda aimed to build a complex model of decision making are suggested. Finally a brief reflection on the study of underground economy is presented. The challenge for the link between psychology and economics is to figure out a descriptive general model of the process of decision making, perhaps by combining weighted elements of the different ways in which human rationality emerges--calculation, rule following, sense-making--for explaining singular and specific decisions.

  4. Semi-classical analysis of optical model ambiguities

    International Nuclear Information System (INIS)

    Cuer, M.

    1979-01-01

    The ambiguities in the inverse problem at fixed energy in quantum mechanics are analyzed in the framework of the JWKB method. When the classical turning point is unique for all values of the impact parameter (high energies region), the ambiguities proceed only from the quantization of the angular momentum. In the asymptotic region the difference between two particular equivalent potentials changes sign infinitely often. In addition, the set of equivalent potentials which have a given asymptotic form is bounded (except perhaps at the origin). When there are several turning points for small values of the impact parameter (low-energy region), new ambiguities arise from the fact that the parts of the potential that are located between turning points are not ''visible'' in the classical limit. The set of equivalent potentials wich have a given asymptotic form is then not bounded. Mumerical examples (of real and complex equivalent potentials) are given. The optical model ambiguities are studied. The potential depth ambiguities also appear in classical mechanics, but their discrete nature is a quantum property. The VR/sup p//sup( V/)=constant ambiguities can be explained by the quantum corrections to the spiral scattering phenomenon. An attempt to explain why ambiguities arise only with heavy particles scattering is also given

  5. Ambiguous walls

    DEFF Research Database (Denmark)

    Mody, Astrid

    2012-01-01

    The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how walls...... have encouraged architectural thinking of enclosure, materiality, construction and inhabitation in architectural history, the paper’s aim is to define new directions for the integration of LEDs in walls, challenging the thinking of inhabitation and program. This paper introduces the notion...... of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...

  6. A preliminary study of the Gribov ambiguity in lattice SU(3) Coulomb gauge

    Energy Technology Data Exchange (ETDEWEB)

    Parrinello, C. (Physics Dept., New York Univ., NY (United States)); Petrarca, S. (Dipt. di Fisica, Rome-1 Univ. (Italy) INFN, Rome (Italy)); Vladikas, A. (Dipt. di Fisica, Rome-2 Univ. (Italy) INFN, Rome (Italy))

    1991-10-10

    We report on simulations of pure SU(3) gauge theory on a 10{sup 3}x20 lattice at {beta}=6.0 in the Coulomb gauge, from which the Gribov ambiguity appears to be maximal, in the sense that the gauge-fixing process is highly unstable with respect to variations of the starting configuration via random gauge transformations. We give a heuristic explanation of the larger number of Gribov copies in such a gauge with respect to the Landau gauge. (orig.).

  7. Individual differences in using geometric and featural cues to maintain spatial orientation: cue quantity and cue ambiguity are more important than cue type.

    Science.gov (United States)

    Kelly, Jonathan W; McNamara, Timothy P; Bodenheimer, Bobby; Carr, Thomas H; Rieser, John J

    2009-02-01

    Two experiments explored the role of environmental cues in maintaining spatial orientation (sense of self-location and direction) during locomotion. Of particular interest was the importance of geometric cues (provided by environmental surfaces) and featural cues (nongeometric properties provided by striped walls) in maintaining spatial orientation. Participants performed a spatial updating task within virtual environments containing geometric or featural cues that were ambiguous or unambiguous indicators of self-location and direction. Cue type (geometric or featural) did not affect performance, but the number and ambiguity of environmental cues did. Gender differences, interpreted as a proxy for individual differences in spatial ability and/or experience, highlight the interaction between cue quantity and ambiguity. When environmental cues were ambiguous, men stayed oriented with either one or two cues, whereas women stayed oriented only with two. When environmental cues were unambiguous, women stayed oriented with one cue.

  8. Gauge-fixing ambiguity and monopole number

    International Nuclear Information System (INIS)

    Hioki, S.; Miyamura, O.

    1991-01-01

    Gauge-fixing ambiguities of lattice SU(2) QCD are studied in the maximally abelian and unitary gauges. In the former, we find local maxima of a gauge-fixing function which may correspond to Gribov copies. There is a definite anti-correlation between the number of monopoles and the value of the function. Errors of measured quantities coming from the ambiguity are found to be less than inherent dispersion in the ensemble average. No ambiguity is found in the unitary gauges. (orig.)

  9. Ambiguous Adaptation

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Lyngsie, Jacob

    and reciprocal adaptation of informal governance structure create ambiguity in situations of contingencies, which, subsequently, increases the likelihood of premature relationship termination. Using a large sample of exchange relationships in the global service provider industry, we find support for a hypothesis...

  10. Eliminating ambiguity in digital signals

    Science.gov (United States)

    Weber, W. J., III

    1979-01-01

    Multiamplitude minimum shift keying (mamsk) transmission system, method of differential encoding overcomes problem of ambiguity associated with advanced digital-transmission techniques with little or no penalty in transmission rate, error rate, or system complexity. Principle of method states, if signal points are properly encoded and decoded, bits are detected correctly, regardless of phase ambiguities.

  11. Productive Ambiguity in the Learning of Mathematics

    Science.gov (United States)

    Foster, Colin

    2011-01-01

    In this paper I take a positive view of ambiguity in the learning of mathematics. Following Grosholz (2007), I argue that it is not only the arts which exploit ambiguity for creative ends but science and mathematics too. By enabling the juxtaposition of multiple conflicting frames of reference, ambiguity allows novel connections to be made. I…

  12. Ambiguous Intimacy

    DEFF Research Database (Denmark)

    Houmøller, Kathrin

    2015-01-01

    relations and intimacy is riddled with inevitability and precarity. Here, it is argued, intimacy is ambiguous: allowed and resisted, longed for and feared - simultaneously encompassing practices of closeness and distance, connecting and disconnecting. To make a life in this particular place sometimes...

  13. Analyzing Ambiguity of Context-Free Grammars

    DEFF Research Database (Denmark)

    Brabrand, Claus; Giegerich, Robert; Møller, Anders

    2007-01-01

    It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. We...... observe that there is a simple linguistic characterization of the grammar ambiguity problem, and we show how to exploit this to conservatively approximate the problem based on local regular approximations and grammar unfoldings. As an application, we consider grammars that occur in RNA analysis...

  14. Perturbative ambiguities in Coulomb gauge QCD

    International Nuclear Information System (INIS)

    Doust, P.

    1987-01-01

    The naive Coulomb gauge Feynman rules in non-abelian gauge theory give rise to ambiguous integrals, in addition to the usual ultraviolet divergences. Generalizing the work of Cheng and Tsai, these ambiguities are resolved to all orders in perturbation theory, by defining a gauge that interpolates smoothly between the Feynman gauge and the Coulomb gauge. The extra terms V 1 +V 2 of Christ and Lee are identified with certain two-loop ambiguous terms. However, there still seem to be unsolved problems connected with renormalisation. copyright 1987 Academic Press, Inc

  15. Ambiguous Genitalia

    Science.gov (United States)

    ... that respond to testosterone. 5a-reductase deficiency. This enzyme defect impairs normal male hormone production. Ambiguous genitalia can also be a feature of certain rare, complex syndromes that affect many organ systems. Risk factors Family history may play a role in the development of ...

  16. Ambiguity and Volatility : Asset Pricing Implications

    NARCIS (Netherlands)

    Pataracchia, B.

    2011-01-01

    Using a simple dynamic consumption-based asset pricing model, this paper explores the implications of a representative investor with smooth ambiguity averse preferences [Klibano¤, Marinacci and Mukerji, Econometrica (2005)] and provides a comparative analysis of risk aversion and ambiguity aversion.

  17. Ambiguity attitudes in decisions for others

    NARCIS (Netherlands)

    König-Kersting, Christian; Trautmann, Stefan

    We probe the pattern of ambiguity aversion for moderate-likelihood gain prospects, and ambiguity seeking for low-likelihood gain prospects, if people make decisions not for themselves but as agents for others. We confirm the pattern both with and without accountability.

  18. Gene name ambiguity of eukaryotic nomenclatures.

    Science.gov (United States)

    Chen, Lifeng; Liu, Hongfang; Friedman, Carol

    2005-01-15

    With more and more scientific literature published online, the effective management and reuse of this knowledge has become problematic. Natural language processing (NLP) may be a potential solution by extracting, structuring and organizing biomedical information in online literature in a timely manner. One essential task is to recognize and identify genomic entities in text. 'Recognition' can be accomplished using pattern matching and machine learning. But for 'identification' these techniques are not adequate. In order to identify genomic entities, NLP needs a comprehensive resource that specifies and classifies genomic entities as they occur in text and that associates them with normalized terms and also unique identifiers so that the extracted entities are well defined. Online organism databases are an excellent resource to create such a lexical resource. However, gene name ambiguity is a serious problem because it affects the appropriate identification of gene entities. In this paper, we explore the extent of the problem and suggest ways to address it. We obtained gene information from 21 organisms and quantified naming ambiguities within species, across species, with English words and with medical terms. When the case (of letters) was retained, official symbols displayed negligible intra-species ambiguity (0.02%) and modest ambiguities with general English words (0.57%) and medical terms (1.01%). In contrast, the across-species ambiguity was high (14.20%). The inclusion of gene synonyms increased intra-species ambiguity substantially and full names contributed greatly to gene-medical-term ambiguity. A comprehensive lexical resource that covers gene information for the 21 organisms was then created and used to identify gene names by using a straightforward string matching program to process 45,000 abstracts associated with the mouse model organism while ignoring case and gene names that were also English words. We found that 85.1% of correctly retrieved mouse

  19. Word Domain Disambiguation via Word Sense Disambiguation

    Energy Technology Data Exchange (ETDEWEB)

    Sanfilippo, Antonio P.; Tratz, Stephen C.; Gregory, Michelle L.

    2006-06-04

    Word subject domains have been widely used to improve the perform-ance of word sense disambiguation al-gorithms. However, comparatively little effort has been devoted so far to the disambiguation of word subject do-mains. The few existing approaches have focused on the development of al-gorithms specific to word domain dis-ambiguation. In this paper we explore an alternative approach where word domain disambiguation is achieved via word sense disambiguation. Our study shows that this approach yields very strong results, suggesting that word domain disambiguation can be ad-dressed in terms of word sense disam-biguation with no need for special purpose algorithms.

  20. Does ambiguity aversion survive in experimental asset markets?

    NARCIS (Netherlands)

    Füllbrunn, Sascha; Rau, Holger A.; Weitzel, Utz

    2014-01-01

    Although a number of theoretical studies explain empirical puzzles in finance with ambiguity aversion, it is not a given that individual ambiguity attitudes survive in markets. In fact, despite ample evidence of ambiguity aversion in individual decision making, most studies find no or only limited

  1. Ambiguities and conventions in the perception of visual art.

    Science.gov (United States)

    Mamassian, Pascal

    2008-09-01

    Vision perception is ambiguous and visual arts play with these ambiguities. While perceptual ambiguities are resolved with prior constraints, artistic ambiguities are resolved by conventions. Is there a relationship between priors and conventions? This review surveys recent work related to these ambiguities in composition, spatial scale, illumination and color, three-dimensional layout, shape, and movement. While most conventions seem to have their roots in perceptual constraints, those conventions that differ from priors may help us appreciate how visual arts differ from everyday perception.

  2. Equity Trading under Heterogeneity in Ambiguity

    DEFF Research Database (Denmark)

    Alonso, Irasema; Prado, Mauricio

    -relevant, but hard-to-interpret information: a situation like that during the onset of the recent crisis in financial markets. During this episode, market participants appeared unsure of the values of a variety of assets, trading all but stopped. Ambiguity aversion, it appears to us, offers a tractable way......-participation - a drastic form of trading less - in the ambiguity-ridden market by certain agents (here we have in mind those with higher levels of ambiguity). This endogenous limited participation on the market also has implications for the relative wealth of agents in an economy. The dynamics of the wealth distribution...

  3. Precise Point Positioning with Partial Ambiguity Fixing.

    Science.gov (United States)

    Li, Pan; Zhang, Xiaohong

    2015-06-10

    Reliable and rapid ambiguity resolution (AR) is the key to fast precise point positioning (PPP). We propose a modified partial ambiguity resolution (PAR) method, in which an elevation and standard deviation criterion are first used to remove the low-precision ambiguity estimates for AR. Subsequently the success rate and ratio-test are simultaneously used in an iterative process to increase the possibility of finding a subset of decorrelated ambiguities which can be fixed with high confidence. One can apply the proposed PAR method to try to achieve an ambiguity-fixed solution when full ambiguity resolution (FAR) fails. We validate this method using data from 450 stations during DOY 021 to 027, 2012. Results demonstrate the proposed PAR method can significantly shorten the time to first fix (TTFF) and increase the fixing rate. Compared with FAR, the average TTFF for PAR is reduced by 14.9% for static PPP and 15.1% for kinematic PPP. Besides, using the PAR method, the average fixing rate can be increased from 83.5% to 98.2% for static PPP, from 80.1% to 95.2% for kinematic PPP respectively. Kinematic PPP accuracy with PAR can also be significantly improved, compared to that with FAR, due to a higher fixing rate.

  4. Semantic Ambiguity Effects in L2 Word Recognition.

    Science.gov (United States)

    Ishida, Tomomi

    2018-06-01

    The present study examined the ambiguity effects in second language (L2) word recognition. Previous studies on first language (L1) lexical processing have observed that ambiguous words are recognized faster and more accurately than unambiguous words on lexical decision tasks. In this research, L1 and L2 speakers of English were asked whether a letter string on a computer screen was an English word or not. An ambiguity advantage was found for both groups and greater ambiguity effects were found for the non-native speaker group when compared to the native speaker group. The findings imply that the larger ambiguity advantage for L2 processing is due to their slower response time in producing adequate feedback activation from the semantic level to the orthographic level.

  5. Processing subject-object ambiguities in Dutch

    NARCIS (Netherlands)

    Kaan, Edith

    1997-01-01

    Various clause types in Dutch and German are at least temporarily ambiguous with respect to the order of subject and object. A number of previous studies regarding the processing of such subject-object ambiguities have reported a preference for a subject-object interpretation. This order preference

  6. SAR Ambiguity Study for the Cassini Radar

    Science.gov (United States)

    Hensley, Scott; Im, Eastwood; Johnson, William T. K.

    1993-01-01

    The Cassini Radar's synthetic aperture radar (SAR) ambiguity analysis is unique with respect to other spaceborne SAR ambiguity analyses owing to the non-orbiting spacecraft trajectory, asymmetric antenna pattern, and burst mode of data collection. By properly varying the pointing, burst mode timing, and radar parameters along the trajectory this study shows that the signal-to-ambiguity ratio of better than 15 dB can be achieved for all images obtained by the Cassini Radar.

  7. Regularization ambiguities in loop quantum gravity

    International Nuclear Information System (INIS)

    Perez, Alejandro

    2006-01-01

    One of the main achievements of loop quantum gravity is the consistent quantization of the analog of the Wheeler-DeWitt equation which is free of ultraviolet divergences. However, ambiguities associated to the intermediate regularization procedure lead to an apparently infinite set of possible theories. The absence of an UV problem--the existence of well-behaved regularization of the constraints--is intimately linked with the ambiguities arising in the quantum theory. Among these ambiguities is the one associated to the SU(2) unitary representation used in the diffeomorphism covariant 'point-splitting' regularization of the nonlinear functionals of the connection. This ambiguity is labeled by a half-integer m and, here, it is referred to as the m ambiguity. The aim of this paper is to investigate the important implications of this ambiguity. We first study 2+1 gravity (and more generally BF theory) quantized in the canonical formulation of loop quantum gravity. Only when the regularization of the quantum constraints is performed in terms of the fundamental representation of the gauge group does one obtain the usual topological quantum field theory as a result. In all other cases unphysical local degrees of freedom arise at the level of the regulated theory that conspire against the existence of the continuum limit. This shows that there is a clear-cut choice in the quantization of the constraints in 2+1 loop quantum gravity. We then analyze the effects of the ambiguity in 3+1 gravity exhibiting the existence of spurious solutions for higher representation quantizations of the Hamiltonian constraint. Although the analysis is not complete in 3+1 dimensions - due to the difficulties associated to the definition of the physical inner product - it provides evidence supporting the definitions quantum dynamics of loop quantum gravity in terms of the fundamental representation of the gauge group as the only consistent possibilities. If the gauge group is SO(3) we find

  8. Ambiguity and violence in adolescent dating relationships.

    Science.gov (United States)

    Draucker, Claire Burke; Martsolf, Donna; Stephenson, Pam Shockey

    2012-08-01

    Little is known about dyadic processes that lead to adolescent dating violence. The purpose of this study was to examine the phenomenon of relationship ambiguity in adolescent dating relationships to better understand how ambiguity contributes to violence and aggression between dating partners. Data were drawn from 88 narratives of young adults who had participated in a study on adolescent dating violence. Interpretive phenomenology was used to produce an in-depth description of the phenomenon of relationship ambiguity. Relationship ambiguity results in differing expectations between partners regarding closeness and intimacy, fidelity, and obligation. These differences lead to conflicts that set the stage for violence and aggression in adolescent dating relationships. A series of recommendations for clinicians working with adolescents are presented. © 2012 Wiley Periodicals, Inc.

  9. Potential Ambiguity Translation Performances within Legal Language Institutional Nomenclature

    Directory of Open Access Journals (Sweden)

    Oţăt Diana

    2015-12-01

    Full Text Available Motivated by a paradoxical corollary of ambiguities in legal documents and especially in contract texts, the current paper underpins a dichotomy approach to unintended ambiguities aiming to establish a referential framework for the occurrence rate of translation ambiguities within the legal language nomenclature. The research focus is on a twofold situation since ambiguities may. on the one hand, arise dining the translation process, generated by the translator’s lack of competence, i.e. inadequate use of English regarding the special nature of legal language, or. on the other hand, they may be simply transferred from the source language into the target language without even noticing the potential ambiguous situation, i.e. culture-bound ambiguities. Hence, the paper proposes a contrastive analysis in order to localize the occurrence of lexical, structural, and socio-cultural ambiguities triggered by the use of the term performance and its Romanian equivalents in a number of sales contracts.

  10. Combined GPS/GLONASS Precise Point Positioning with Fixed GPS Ambiguities

    Science.gov (United States)

    Pan, Lin; Cai, Changsheng; Santerre, Rock; Zhu, Jianjun

    2014-01-01

    Precise point positioning (PPP) technology is mostly implemented with an ambiguity-float solution. Its performance may be further improved by performing ambiguity-fixed resolution. Currently, the PPP integer ambiguity resolutions (IARs) are mainly based on GPS-only measurements. The integration of GPS and GLONASS can speed up the convergence and increase the accuracy of float ambiguity estimates, which contributes to enhancing the success rate and reliability of fixing ambiguities. This paper presents an approach of combined GPS/GLONASS PPP with fixed GPS ambiguities (GGPPP-FGA) in which GPS ambiguities are fixed into integers, while all GLONASS ambiguities are kept as float values. An improved minimum constellation method (MCM) is proposed to enhance the efficiency of GPS ambiguity fixing. Datasets from 20 globally distributed stations on two consecutive days are employed to investigate the performance of the GGPPP-FGA, including the positioning accuracy, convergence time and the time to first fix (TTFF). All datasets are processed for a time span of three hours in three scenarios, i.e., the GPS ambiguity-float solution, the GPS ambiguity-fixed resolution and the GGPPP-FGA resolution. The results indicate that the performance of the GPS ambiguity-fixed resolutions is significantly better than that of the GPS ambiguity-float solutions. In addition, the GGPPP-FGA improves the positioning accuracy by 38%, 25% and 44% and reduces the convergence time by 36%, 36% and 29% in the east, north and up coordinate components over the GPS-only ambiguity-fixed resolutions, respectively. Moreover, the TTFF is reduced by 27% after adding GLONASS observations. Wilcoxon rank sum tests and chi-square two-sample tests are made to examine the significance of the improvement on the positioning accuracy, convergence time and TTFF. PMID:25237901

  11. Combined GPS/GLONASS Precise Point Positioning with Fixed GPS Ambiguities

    Directory of Open Access Journals (Sweden)

    Lin Pan

    2014-09-01

    Full Text Available Precise point positioning (PPP technology is mostly implemented with an ambiguity-float solution. Its performance may be further improved by performing ambiguity-fixed resolution. Currently, the PPP integer ambiguity resolutions (IARs are mainly based on GPS-only measurements. The integration of GPS and GLONASS can speed up the convergence and increase the accuracy of float ambiguity estimates, which contributes to enhancing the success rate and reliability of fixing ambiguities. This paper presents an approach of combined GPS/GLONASS PPP with fixed GPS ambiguities (GGPPP-FGA in which GPS ambiguities are fixed into integers, while all GLONASS ambiguities are kept as float values. An improved minimum constellation method (MCM is proposed to enhance the efficiency of GPS ambiguity fixing. Datasets from 20 globally distributed stations on two consecutive days are employed to investigate the performance of the GGPPP-FGA, including the positioning accuracy, convergence time and the time to first fix (TTFF. All datasets are processed for a time span of three hours in three scenarios, i.e., the GPS ambiguity-float solution, the GPS ambiguity-fixed resolution and the GGPPP-FGA resolution. The results indicate that the performance of the GPS ambiguity-fixed resolutions is significantly better than that of the GPS ambiguity-float solutions. In addition, the GGPPP-FGA improves the positioning accuracy by 38%, 25% and 44% and reduces the convergence time by 36%, 36% and 29% in the east, north and up coordinate components over the GPS-only ambiguity-fixed resolutions, respectively. Moreover, the TTFF is reduced by 27% after adding GLONASS observations. Wilcoxon rank sum tests and chi-square two-sample tests are made to examine the significance of the improvement on the positioning accuracy, convergence time and TTFF.

  12. Concept analysis: Role ambiguity in senior nursing students.

    Science.gov (United States)

    Kalkman, Beth

    2018-04-01

    Role ambiguity is a lack of clarity or uncertainty related to one's position or role. Role ambiguity has been documented in the literature in relationship to athletics, industry, business, education, and nursing. However, a concept analysis has not been performed. Therefore, the process of concept analysis outlined by Walker and Avant is now used to look at the concept of role ambiguity and its relevance to senior nursing students' socialization and education into the profession of nursing. Attributes, antecedents, consequences, and empiric referents are discussed and theories commonly associated with role ambiguity are presented. At the end of the analysis, an operational definition is provided for use in exploring the concept of role ambiguity as it relates to senior nursing students' articulation of the role of the professional nurse. © 2017 Wiley Periodicals, Inc.

  13. Ambiguous science and the visual representation of the real

    Science.gov (United States)

    Newbold, Curtis Robert

    The emergence of visual media as prominent and even expected forms of communication in nearly all disciplines, including those scientific, has raised new questions about how the art and science of communication epistemologically affect the interpretation of scientific phenomena. In this dissertation I explore how the influence of aesthetics in visual representations of science inevitably creates ambiguous meanings. As a means to improve visual literacy in the sciences, I call awareness to the ubiquity of visual ambiguity and its importance and relevance in scientific discourse. To do this, I conduct a literature review that spans interdisciplinary research in communication, science, art, and rhetoric. Furthermore, I create a paradoxically ambiguous taxonomy, which functions to exploit the nuances of visual ambiguities and their role in scientific communication. I then extrapolate the taxonomy of visual ambiguity and from it develop an ambiguous, rhetorical heuristic, the Tetradic Model of Visual Ambiguity. The Tetradic Model is applied to a case example of a scientific image as a demonstration of how scientific communicators may increase their awareness of the epistemological effects of ambiguity in the visual representations of science. I conclude by demonstrating how scientific communicators may make productive use of visual ambiguity, even in communications of objective science, and I argue how doing so strengthens scientific communicators' visual literacy skills and their ability to communicate more ethically and effectively.

  14. Clarity and ambiguity in strategic corporate communication

    DEFF Research Database (Denmark)

    Gulbrandsen, Ib Tunby

    2017-01-01

    as they are decoupled from the strategy itself. Research limitations/implications – As the findings are based on a study of the understanding and practice of corporate communication strategy in one concrete organization, the study points to the need for additional explorations and examinations of ambiguity in strategic...... how they perceived the writing, reading and enactment of their organization’s new corporate communication strategy. Findings – The analysis reveals the presence of both clarity and ambiguity in the employees’ understanding of the strategy. Both in terms of formulation and implementation. For instance...... corporate communication. Originality/value – Despite numerous studies on the presence of ambiguity in strategy making in the neighbouring field of strategic management, the majority of strategic corporate communication literature largely treats ambiguity as something that should be absent. This has caused...

  15. Clarity and ambiguity in strategic corporate communication

    DEFF Research Database (Denmark)

    Gulbrandsen, Ib Tunby

    2018-01-01

    as they are decoupled from the strategy itself. Research limitations/implications – As the findings are based on a study of the understanding and practice of corporate communication strategy in one concrete organization, the study points to the need for additional explorations and examinations of ambiguity in strategic...... how they perceived the writing, reading and enactment of their organization’s new corporate communication strategy. Findings – The analysis reveals the presence of both clarity and ambiguity in the employees’ understanding of the strategy. Both in terms of formulation and implementation. For instance...... corporate communication. Originality/value – Despite numerous studies on the presence of ambiguity in strategy making in the neighbouring field of strategic management, the majority of strategic corporate communication literature largely treats ambiguity as something that should be absent. This has caused...

  16. Risk Management and Insurance Decisions under Ambiguity

    DEFF Research Database (Denmark)

    Martínez-Correa, Jimmy

    I study the impact of ambiguity on insurance decisions and the optimality of insurance contracts. My tractable approach allows me to study the interaction between risk and ambiguity attitudes. When insurance decisions are made independently of other assets, for a given increase in wealth, both risk...... portfolio theory that assumes Subjective Expected Utility theory; however, it provides hints to a possible solution of the under-diversification puzzle of households. I also identify conditions under which more risk or ambiguity aversion decreases the demand for coinsurance. Additionally, I show...... a counterexample to a classical result in insurance economics where an insurance contract with straight deductible is dominated by a coinsurance contract. Finally, I find that a modified Borch rule characterizes the optimal insurance contract with bilateral risk and ambiguity attitudes and heterogeneity in beliefs....

  17. Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model.

    Science.gov (United States)

    Grau-Moya, Jordi; Ortega, Pedro A; Braun, Daniel A

    2016-01-01

    A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects' choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects' choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain.

  18. Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model.

    Directory of Open Access Journals (Sweden)

    Jordi Grau-Moya

    Full Text Available A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects' choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects' choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain.

  19. Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model

    Science.gov (United States)

    Grau-Moya, Jordi; Ortega, Pedro A.; Braun, Daniel A.

    2016-01-01

    A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects’ choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects’ choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain. PMID:27124723

  20. The Ethics of Strategic Ambiguity: Contrasting Teleologically and Deontologically Based Experiences.

    Science.gov (United States)

    Paul, Jim; And Others

    This paper describes ethical considerations in the use of strategic ambiguity in organizational communication. Ambiguity is defined as "experienced ambiguity" and is distinct from uncertainty and equivocality which are properties of a stimulus. Strategic ambiguity is the use of "calculated ambiguity" in organizations to achieve…

  1. Global optimization applied to GPS positioning by ambiguity functions

    International Nuclear Information System (INIS)

    Baselga, Sergio

    2010-01-01

    Differential GPS positioning with carrier-phase observables is commonly done in a process that involves determination of the unknown integer ambiguity values. An alternative approach, named the ambiguity function method, was already proposed in the early days of GPS positioning. By making use of a trigonometric function ambiguity unknowns are eliminated from the functional model before the estimation process. This approach has significant advantages, such as ease of use and insensitivity to cycle slips, but requires such high accuracy in the initial approximate coordinates that its use has been practically dismissed from consideration. In this paper a novel strategy is proposed so that the need for highly accurate initial coordinates disappears: the application of a global optimization method to the ambiguity functions model. The use of this strategy enables the ambiguity function method to compete with the present prevailing approach of ambiguity resolution

  2. Blunted Ambiguity Aversion During Cost-Benefit Decisions in Antisocial Individuals.

    Science.gov (United States)

    Buckholtz, Joshua W; Karmarkar, Uma; Ye, Shengxuan; Brennan, Grace M; Baskin-Sommers, Arielle

    2017-05-17

    Antisocial behavior is often assumed to reflect aberrant risk processing. However, many of the most significant forms of antisocial behavior, including crime, reflect the outcomes of decisions made under conditions of ambiguity rather than risk. While risk and ambiguity are formally distinct and experimentally dissociable, little is known about ambiguity sensitivity in individuals who engage in chronic antisocial behavior. We used a financial decision-making task in a high-risk community-based sample to test for associations between sensitivity to ambiguity, antisocial behavior, and arrest history. Sensitivity to ambiguity was lower in individuals who met diagnostic criteria for Antisocial Personality Disorder. Lower ambiguity sensitivity was also associated with higher externalizing (but not psychopathy) scores, and with higher levels of aggression (but not rule-breaking). Finally, blunted sensitivity to ambiguity also predicted a greater frequency of arrests. Together, these data suggest that alterations in cost-benefit decision-making under conditions of ambiguity may promote antisocial behavior.

  3. Pricing risk and ambiguity: the effect of perspective taking.

    Science.gov (United States)

    Trautmann, Stefan T; Schmidt, Ulrich

    2012-01-01

    In the valuation of uncertain prospects, a difference is often observed between selling and buying perspectives. This paper distinguishes between risk (known probabilities) and ambiguity (unknown probabilities) in decisions under uncertainty and shows that the valuation disparity increases under ambiguity compared to risk. It is found that both the comparative versus noncomparative evaluation of risky and ambiguous prospects and the uniqueness of the valuation perspective (either seller or buyer) moderate this increase in the disparity under ambiguity. The finding is consistent with recent theoretical accounts of pricing under uncertainty. We discuss implications for market behaviour and for the ambiguity paradigm as a research tool.

  4. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence*

    Science.gov (United States)

    Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

    2017-01-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks. PMID:28458446

  5. Ambiguity aversion and household portfolio choice puzzles: Empirical evidence.

    Science.gov (United States)

    Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

    2016-03-01

    We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks.

  6. Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

    DEFF Research Database (Denmark)

    Munk, Claus; Rubtsov, Alexey Vladimirovich

    2014-01-01

    prices. The investor is ambiguous about the inflation model and prefers a portfolio strategy which is robust to model misspecification. Ambiguity about the inflation dynamics is shown to affect the optimal portfolio fundamentally different than ambiguity about the price dynamics of traded assets...

  7. The segmentation of sub-lexical morphemes in English-learning 15-month-olds

    Directory of Open Access Journals (Sweden)

    Toben H. Mintz

    2013-02-01

    Full Text Available In most human languages, important components of linguistic structure are carried by affixes, also called bound morphemes. The affixes in a language comprise a relatively small but frequently occurring set of forms that surface as parts of words, but never occur without a stem. They combine productively with word stems and other grammatical entities in systematic and predictable ways. For example, the English suffix –ing occurs on verb stems, and in combination with a form of the auxiliary verb be, marks the verb with progressive aspect (e.g., was walking. In acquiring a language, learners must acquire rules of combination for affixes. However, prior to learning these combinatorial rules, learners are faced with discovering what the sub-lexical forms are over which the rules operate. That is, they have to discover the bound morphemes themselves. It is not known when English-learners begin to analyze words into morphological units. Previous research with learners of English found evidence that 18-month-olds have started to learn the combinatorial rules involving bound morphemes, and that 15-month-olds have not. However, it is not known whether 15-month-olds nevertheless represent the morphemes as distinct entities. This present study demonstrates that when 15-month-olds process words that end in ¬–ing, they segment ¬the suffix from the word, but they do not do so with endings that are not morphemes. Eight-month olds do not show this capacity. Thus, 15-month-olds have already started to identify bound morphemes and actively use them in processing speech.

  8. Discrete ambiguities in CP-violating asymmetries in B decays

    International Nuclear Information System (INIS)

    London, David

    1998-01-01

    The CP-angles α, β and γ can be extracted from CP-violating asymmetries in the B system, but only up to discrete ambiguities. These discrete ambiguities make it difficult to determine with certainty whether or not new physics is present. I show that, if the condition α+β+γ=π is imposed, there remains a twofold ambiguity in the CP-angle set (α,β,γ), and I discuss ways to cleanly resolve this final discrete ambiguity

  9. An ambiguity in fermionic string perturbation theory

    International Nuclear Information System (INIS)

    Atick, J.J.; Rabin, J.M.

    1988-01-01

    Recent investigation by Verlinde and Verlinde has shown that the fermionic string loop amplitudes change by a total derivative term in the moduli space under a change of basis of the supermoduli. This ambiguity is addressed in the context of the heterotic string theory, and shown to be a consequence of an inherent ambiguity in defining integration over the variables of a Grassmann algebra - in this case the Grassmann-valued coordinates of the supermoduli space. A resolution of this ambiguity in genus-two within this formalism is also presented. (orig.)

  10. Characteristics of a pure-state ambiguity function

    International Nuclear Information System (INIS)

    Praxmeyer, Ludmila; Vitanov, Nikolay; Stenholm, Stig

    2009-01-01

    We present the necessary and sufficient condition for a square integrable function on R 2N to be an ambiguity function corresponding to a square integrable function on R N . This condition has the form of an integral equation. We also list some easier to check necessary conditions that must be fulfilled by a function that is an ambiguity function of a pure state. We show how to construct a wavefunction corresponding to a given ambiguity function and we present examples of how our formal results can be used in practice.

  11. Comparing Tolerance of Ambiguity in Veterinary and Medical Students.

    Science.gov (United States)

    Hancock, Jason; Hammond, Jennifer A; Roberts, Martin; Mattick, Karen

    Current guidelines suggest that educators in both medical and veterinary professions should do more to ensure that students can tolerate ambiguity. Designing curricula to achieve this requires the ability to measure and understand differences in ambiguity tolerance among and within professional groups. Although scales have been developed to measure tolerance of ambiguity in both medical and veterinary professions, no comparative studies have been reported. We compared the tolerance of ambiguity of medical and veterinary students, hypothesizing that veterinary students would have higher tolerance of ambiguity, given the greater patient diversity and less well-established evidence base underpinning practice. We conducted a secondary analysis of questionnaire data from first- to fourth-year medical and veterinary students. Tolerance of ambiguity scores were calculated and compared using the TAMSAD scale (29 items validated for the medical student population), the TAVS scale (27 items validated for the veterinary student population), and a scale comprising the 22 items common to both scales. Using the TAMSAD and TAVS scales, medical students had a significantly higher mean tolerance of ambiguity score than veterinary students (56.1 vs. 54.1, pambiguity than veterinary students, although this depends on the scale used.

  12. Ambiguous Adaptation

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Lyngsie, Jacob

    2017-01-01

    We investigate the connection between contract duration, relational mechanisms, and premature relationship termination. Based on an analysis of a large sample of exchange relationships in the global service-provider industry, we argue that investments in either longer contract duration or more in...... ambiguous reference points for adaption and thus increase the likelihood of premature termination by restricting the parties' set of adaptive actions....

  13. Crichton ambiguities with infinitely many partial waves

    NARCIS (Netherlands)

    Atkinson, D.; Kok, L.P.; de Roo, M.

    We construct families of spin less two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are

  14. Ambiguity, Ambivalence and Extravagance in The Hunger Games

    OpenAIRE

    Oliver, Kelly

    2014-01-01

    I argue that Katniss Everdeen from The Hunger Games is an emblem of what Julia Kristeva calls the “extravagant girl” who wants to have it all and to be the best at everything. Katniss has an ambiguous gender identity, both masculine and feminine, paternal and maternal. And she has ambivalent desires. I conclude that this ambiguity and ambivalence open up new possibilities for girls and initiate an aesthetics of ambiguity.

  15. Children do not exhibit ambiguity aversion despite intact familiarity bias.

    Science.gov (United States)

    Li, Rosa; Brannon, Elizabeth M; Huettel, Scott A

    2014-01-01

    The phenomenon of ambiguity aversion, in which risky gambles with known probabilities are preferred over ambiguous gambles with unknown probabilities, has been thoroughly documented in adults but never measured in children. Here, we use two distinct tasks to investigate ambiguity preferences of children (8- to 9-year-olds) and a comparison group of adults (19- to 27-year-olds). Across three separate measures, we found evidence for significant ambiguity aversion in adults but not in children and for greater ambiguity aversion in adults compared to children. As ambiguity aversion in adults has been theorized to result from a preference to bet on the known and avoid the unfamiliar, we separately measured familiarity bias and found that children, like adults, are biased towards the familiar. Our findings indicate that ambiguity aversion emerges across the course of development between childhood and adolescence, while a familiarity bias is already present in childhood.

  16. Azimuth Phase Coding for Range Ambiguity Suppression in SAR

    DEFF Research Database (Denmark)

    Dall, Jørgen; Kusk, Anders

    2004-01-01

    A novel ambiguity suppression technique is proposed. Range ambiguities in synthetic aperture radar (SAR) images are eliminated with an azimuth filter after having applied an azimuth phase modulation to the transmitted pulses and a corresponding demodulation to the received pulses. The technique...... excels by actually eliminating the ambiguities rather than just defocusing them as most other techniques do. This makes the proposed technique applicable to distributed targets. The range ambiguity suppression permits the pulse repetition frequency (PRF) to exceed the upper limit otherwise defined...... by the antenna elevation dimension. The fundamental antenna area constraint still applies, but the PRF can be chosen with more freedom. In addition to ambiguity suppression, potential applications include nadir return elimination and signal-to-noise ratio improvement....

  17. Constraints and Ambiguity

    DEFF Research Database (Denmark)

    Dove, Graham; Biskjær, Michael Mose; Lundqvist, Caroline Emilie

    2017-01-01

    groups of students building three models each. We studied groups building with traditional plastic bricks and also using a digital environment. The building tasks students undertake, and our subsequent analysis, are informed by the role constraints and ambiguity play in creative processes. Based...

  18. Does ambiguity aversion influence the framing effect during decision making?

    Science.gov (United States)

    Osmont, Anaïs; Cassotti, Mathieu; Agogué, Marine; Houdé, Olivier; Moutier, Sylvain

    2015-04-01

    Decision-makers present a systematic tendency to avoid ambiguous options for which the level of risk is unknown. This ambiguity aversion is one of the most striking decision-making biases. Given that human choices strongly depend on the options' presentation, the purpose of the present study was to examine whether ambiguity aversion influences the framing effect during decision making. We designed a new financial decision-making task involving the manipulation of both frame and uncertainty levels. Thirty-seven participants had to choose between a sure option and a gamble depicting either clear or ambiguous probabilities. The results revealed a clear preference for the sure option in the ambiguity condition regardless of frame. However, participants presented a framing effect in both the risk and ambiguity conditions. Indeed, the framing effect was bidirectional in the risk condition and unidirectional in the ambiguity condition given that it did not involve preference reversal but only a more extreme choice tendency.

  19. Measuring Ambiguity in HLA Typing Methods

    Science.gov (United States)

    Madbouly, Abeer; Freeman, John; Maiers, Martin

    2012-01-01

    In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched), but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure objectively evaluates HLA

  20. Measuring ambiguity in HLA typing methods.

    Directory of Open Access Journals (Sweden)

    Vanja Paunić

    Full Text Available In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched, but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure

  1. Triple-frequency GPS precise point positioning with rapid ambiguity resolution

    Science.gov (United States)

    Geng, Jianghui; Bock, Yehuda

    2013-05-01

    At present, reliable ambiguity resolution in real-time GPS precise point positioning (PPP) can only be achieved after an initial observation period of a few tens of minutes. In this study, we propose a method where the incoming triple-frequency GPS signals are exploited to enable rapid convergences to ambiguity-fixed solutions in real-time PPP. Specifically, extra-wide-lane ambiguity resolution can be first achieved almost instantaneously with the Melbourne-Wübbena combination observable on L2 and L5. Then the resultant unambiguous extra-wide-lane carrier-phase is combined with the wide-lane carrier-phase on L1 and L2 to form an ionosphere-free observable with a wavelength of about 3.4 m. Although the noise of this observable is around 100 times the raw carrier-phase noise, its wide-lane ambiguity can still be resolved very efficiently, and the resultant ambiguity-fixed observable can assist much better than pseudorange in speeding up succeeding narrow-lane ambiguity resolution. To validate this method, we use an advanced hardware simulator to generate triple-frequency signals and a high-grade receiver to collect 1-Hz data. When the carrier-phase precisions on L1, L2 and L5 are as poor as 1.5, 6.3 and 1.5 mm, respectively, wide-lane ambiguity resolution can still reach a correctness rate of over 99 % within 20 s. As a result, the correctness rate of narrow-lane ambiguity resolution achieves 99 % within 65 s, in contrast to only 64 % within 150 s in dual-frequency PPP. In addition, we also simulate a multipath-contaminated data set and introduce new ambiguities for all satellites every 120 s. We find that when multipath effects are strong, ambiguity-fixed solutions are achieved at 78 % of all epochs in triple-frequency PPP whilst almost no ambiguities are resolved in dual-frequency PPP. Therefore, we demonstrate that triple-frequency PPP has the potential to achieve ambiguity-fixed solutions within a few minutes, or even shorter if raw carrier-phase precisions are

  2. Knowledge-based biomedical word sense disambiguation: comparison of approaches

    Directory of Open Access Journals (Sweden)

    Aronson Alan R

    2010-11-01

    Full Text Available Abstract Background Word sense disambiguation (WSD algorithms attempt to select the proper sense of ambiguous terms in text. Resources like the UMLS provide a reference thesaurus to be used to annotate the biomedical literature. Statistical learning approaches have produced good results, but the size of the UMLS makes the production of training data infeasible to cover all the domain. Methods We present research on existing WSD approaches based on knowledge bases, which complement the studies performed on statistical learning. We compare four approaches which rely on the UMLS Metathesaurus as the source of knowledge. The first approach compares the overlap of the context of the ambiguous word to the candidate senses based on a representation built out of the definitions, synonyms and related terms. The second approach collects training data for each of the candidate senses to perform WSD based on queries built using monosemous synonyms and related terms. These queries are used to retrieve MEDLINE citations. Then, a machine learning approach is trained on this corpus. The third approach is a graph-based method which exploits the structure of the Metathesaurus network of relations to perform unsupervised WSD. This approach ranks nodes in the graph according to their relative structural importance. The last approach uses the semantic types assigned to the concepts in the Metathesaurus to perform WSD. The context of the ambiguous word and semantic types of the candidate concepts are mapped to Journal Descriptors. These mappings are compared to decide among the candidate concepts. Results are provided estimating accuracy of the different methods on the WSD test collection available from the NLM. Conclusions We have found that the last approach achieves better results compared to the other methods. The graph-based approach, using the structure of the Metathesaurus network to estimate the relevance of the Metathesaurus concepts, does not perform well

  3. Isoclinic Ambiguity Unwrapping of Circular Ring under Diametric Compression

    Directory of Open Access Journals (Sweden)

    Huang M.-J.

    2010-06-01

    Full Text Available Isoclinic and isochromatic parameters in photoelastic analysis are formulated by arc tangent function of several phase shifting frames but for isochromatic calculation it is, in addition, in terms of isoclinic data also. Thus, any isoclinic phase ambiguity would also result in the phase inconsistencies of isochromatic calculation and cause unwrapping problems and difficulties. Many methods had been proposed to treat these kinds of isochromatic fringes but lots of treatments were needed for the correct retrieval. In this work, the isoclinic ambiguity problem is investigated and solved directly by a novel regional phase unwrapping technique. Once the isoclinic phase ambiguity problems are solved, a correct isoclinic result can be obtained. Then, substituting this result into the isochromatic formation yields an ambiguity free isochromatic phase map, which can be easily restored by any phase unwrapping algorithm. A stress frozen sample - circular ring under diametric compression verifies its effectiveness. Usually happened is that this kind of sample is with ambiguous isoclinic data which would cause phase ambiguities of the isochromatic formulation if not treated well first.

  4. Estimating ambiguity preferences and perceptions in multiple prior models: Evidence from the field.

    Science.gov (United States)

    Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

    2015-12-01

    We develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of moderate to high likelihood involving gains, but ambiguity seeking prevails for low likelihoods and for losses. We show that choices made under ambiguity in the gain domain are best explained by the α-MaxMin model, with one parameter measuring ambiguity aversion (ambiguity preferences) and a second parameter quantifying the perceived degree of ambiguity (perceptions about ambiguity). The ambiguity aversion parameter α is constant and prior probability sets are asymmetric for low and high likelihood events. The data reject several other models, such as MaxMin and MaxMax, as well as symmetric probability intervals. Ambiguity aversion and the perceived degree of ambiguity are both higher for men and for the college-educated. Ambiguity aversion (but not perceived ambiguity) is also positively related to risk aversion. In the loss domain, we find evidence of reflection, implying that ambiguity aversion for gains tends to reverse into ambiguity seeking for losses. Our model's estimates for preferences and perceptions about ambiguity can be used to analyze the economic and financial implications of such preferences.

  5. Estimating ambiguity preferences and perceptions in multiple prior models: Evidence from the field

    Science.gov (United States)

    Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

    2016-01-01

    We develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of moderate to high likelihood involving gains, but ambiguity seeking prevails for low likelihoods and for losses. We show that choices made under ambiguity in the gain domain are best explained by the α-MaxMin model, with one parameter measuring ambiguity aversion (ambiguity preferences) and a second parameter quantifying the perceived degree of ambiguity (perceptions about ambiguity). The ambiguity aversion parameter α is constant and prior probability sets are asymmetric for low and high likelihood events. The data reject several other models, such as MaxMin and MaxMax, as well as symmetric probability intervals. Ambiguity aversion and the perceived degree of ambiguity are both higher for men and for the college-educated. Ambiguity aversion (but not perceived ambiguity) is also positively related to risk aversion. In the loss domain, we find evidence of reflection, implying that ambiguity aversion for gains tends to reverse into ambiguity seeking for losses. Our model’s estimates for preferences and perceptions about ambiguity can be used to analyze the economic and financial implications of such preferences. PMID:26924890

  6. Betwixt and between: Role conflict, role ambiguity and role definition in project-based dual-leadership structures.

    Science.gov (United States)

    Ebbers, Joris J; Wijnberg, Nachoem M

    2017-11-01

    Project-based organizations in the film industry usually have a dual-leadership structure, based on a division of tasks between the dual leaders - the director and the producer - in which the former is predominantly responsible for the artistic and the latter for the commercial aspects of the film. These organizations also have a role hierarchically below and between the dual leaders: the 1st assistant director. This organizational constellation is likely to lead to role conflict and role ambiguity experienced by the person occupying that particular role. Although prior studies found negative effects of role conflict and role ambiguity, this study shows they can also have beneficial effects because they create space for defining the role expansively that, in turn, can be facilitated by the dual leaders defining their own roles more narrowly. In a more general sense, this study also shows the usefulness of analyzing the antecedents and consequences of roles, role definition, and role crafting in connection to the behavior of occupants of adjacent roles.

  7. Sense of place in natural resource recreation and tourism: an evaluation and assessment of research findings.

    Science.gov (United States)

    Jennifer Farnum; Troy Hall; Linda E. Kruger

    2005-01-01

    Understanding sense of place and related concepts often presents challenges for both managers and researchers. Inconsistent application of terms, questions regarding their origin, and a lack of awareness of research findings contribute to the ambiguity of these concepts. This integrative review of research provides relevant, current information on the role of sense of...

  8. The dark side of ambiguous discrimination: how state self-esteem moderates emotional and behavioural responses to ambiguous and unambiguous discrimination.

    Science.gov (United States)

    Cihangir, Sezgin; Barreto, Manuela; Ellemers, Naomi

    2010-03-01

    Two experiments examine how experimentally induced differences in state self-esteem moderate emotional and behavioural responses to ambiguous and unambiguous discrimination. Study 1 (N=108) showed that participants who were exposed to ambiguous discrimination report more negative self-directed emotions when they have low compared to high self-esteem. These differences did not emerge when participants were exposed to unambiguous discrimination. Study 2 (N=118) additionally revealed that self-esteem moderated the effect of ambiguous discrimination on self-concern, task performance, and self-stereotyping. Results show that ambiguous discrimination caused participants with low self-esteem to report more negative self-directed emotions, more self-concern, an inferior task performance, and more self-stereotyping, compared to participants in the high self-esteem condition. Emotional and behavioural responses to unambiguous discrimination did not depend on the induced level of self-esteem in these studies.

  9. Crichton ambiguities with infinitely many partial waves

    International Nuclear Information System (INIS)

    Atkinson, D.; Kok, L.P.; de Roo, M.

    1978-01-01

    We construct families of spinless two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are merely special cases of the newly constructed examples

  10. Coding of level of ambiguity within neural systems mediating choice.

    Science.gov (United States)

    Lopez-Paniagua, Dan; Seger, Carol A

    2013-01-01

    Data from previous neuroimaging studies exploring neural activity associated with uncertainty suggest varying levels of activation associated with changing degrees of uncertainty in neural regions that mediate choice behavior. The present study used a novel task that parametrically controlled the amount of information hidden from the subject; levels of uncertainty ranged from full ambiguity (no information about probability of winning) through multiple levels of partial ambiguity, to a condition of risk only (zero ambiguity with full knowledge of the probability of winning). A parametric analysis compared a linear model in which weighting increased as a function of level of ambiguity, and an inverted-U quadratic models in which partial ambiguity conditions were weighted most heavily. Overall we found that risk and all levels of ambiguity recruited a common "fronto-parietal-striatal" network including regions within the dorsolateral prefrontal cortex, intraparietal sulcus, and dorsal striatum. Activation was greatest across these regions and additional anterior and superior prefrontal regions for the quadratic function which most heavily weighs trials with partial ambiguity. These results suggest that the neural regions involved in decision processes do not merely track the absolute degree ambiguity or type of uncertainty (risk vs. ambiguity). Instead, recruitment of prefrontal regions may result from greater degree of difficulty in conditions of partial ambiguity: when information regarding reward probabilities important for decision making is hidden or not easily obtained the subject must engage in a search for tractable information. Additionally, this study identified regions of activity related to the valuation of potential gains associated with stimuli or options (including the orbitofrontal and medial prefrontal cortices and dorsal striatum) and related to winning (including orbitofrontal cortex and ventral striatum).

  11. Ambiguities in the reaction mechanism for (e,e'N)

    International Nuclear Information System (INIS)

    Forest, T. de Jr.

    1984-01-01

    The primary motivation for performing quasi-elastic (e,e'N) experiments revolves around the plane wave impulse approximation (PWIA) description of this reaction. Since the PWIA is an approximation, corrections are necessary in practice in order to extract the desired nuclear structure. Unless one understands the physics behind these corrections this introduces ambiguities. In fact the PWIA itself is an ambiguous prescription since a 'free' off-shell cross section is not a well-defined concept. It is these ambiguities which are discussed in this talk. Most of the paper is devoted to the ambiguities associated with the electromagnetic interaction. The author concentrates on four topics: (1) the interaction of the electron with the nucleus in general; (2) ambiguities in the application of the impulse approximation; (3) the sigma-omega model; and (4) the Coulomb sum rule. (Auth.)

  12. Gauge ambiguities in (rvec e,e'rvec N) reactions

    International Nuclear Information System (INIS)

    Kelly, J.J.

    1997-01-01

    We examine the sensitivity of the distorted-wave impulse approximation for single-nucleon electromagnetic knockout from valence orbitals to ambiguities in the one-body current operator. Violations of current conservation are classified as gauge ambiguities, whereas the elements of a particular class of structural differences off shell are labeled Gordon ambiguities. Gauge ambiguities in differential cross sections and longitudinal response functions are found to increase with missing momentum and to become particularly severe for low-Q 2 kinematical conditions that are far from quasifree but are sometimes used to investigate correlations. The azimuthal asymmetry may provide a useful experimental means for selecting a gauge. Gordon ambiguities increase with Q 2 and are larger for relativistic than for nonrelativistic approaches. Because ambiguities in the one-body current are at least as large as effects due to correlations and there are additional uncertainties due to two-body currents, final-state interactions, and relativistic distortion, we conclude that is unlikely that information about correlations can be extracted from single-nucleon knockout from valence orbitals at large missing momentum. On the other hand, gauge and Gordon ambiguities and uncertainties in final-state interactions have very little effect upon the helicity-dependent recoil polarization, which can be used to investigate the roles of two-body currents and/or possible medium modifications of the one-body current. copyright 1997 The American Physical Society

  13. There is a continuum ambiguity for elastic πN amplitudes

    International Nuclear Information System (INIS)

    Atkinson, D.; Roo, M. de; Polman, T.J.T.M.

    1984-01-01

    The implicit-function method of constructing phase-factor continuum ambiguities in phase-shift analysis is briefly reviewed, and new numerical examples are given of ambiguities in πN phase shifts at 1997 MeV. Since the ambiguous amplitudes differ by more than 5%, while the corresponding cross sections and polarizations are equal, to better than a computational accuracy of 0.007%, numerical credence is given to the theoretical claim that the continuum ambiguity exists. (orig.)

  14. The Communicative Function of Ambiguity in Language

    Science.gov (United States)

    Piantadosi, Steven T.; Tily, Harry; Gibson, Edward

    2012-01-01

    We present a general information-theoretic argument that all efficient communication systems will be ambiguous, assuming that context is informative about meaning. We also argue that ambiguity allows for greater ease of processing by permitting efficient linguistic units to be re-used. We test predictions of this theory in English, German, and…

  15. Localizing Expression of Ambiguity

    National Research Council Canada - National Science Library

    Bear, John; Hobbs, Sr, Jerry R

    1987-01-01

    In this paper we describe an implemented program for localizing the expression of many types of syntactic ambiguity, in the logical forms of sentences, in a manner convenient for subsequent inferential processing...

  16. Intolerance for approach of ambiguity in social anxiety disorder.

    Science.gov (United States)

    Kuckertz, Jennie M; Strege, Marlene V; Amir, Nader

    2017-06-01

    Previous research has utilised the approach-avoidance task (AAT) to measure approach and avoidance action tendencies in socially anxious individuals. "Neutral" social stimuli may be perceived as ambiguous and hence threatening to socially anxious individuals, however it is unclear whether this results in difficulty approaching ambiguous ("neutral") versus unambiguous threat (e.g. disgust) faces (i.e. intolerance of ambiguity). Thirty participants with social anxiety disorder (SADs) and 29 non-anxious controls completed an implicit AAT in which they were instructed to approach or avoid neutral and disgust faces (i.e. pull or push a joystick) based on colour of the picture border. Results indicated that SADs demonstrated greater difficulty approaching neutral relative to disgust faces. Moreover, intolerance for approach of ambiguity predicted social anxiety severity while controlling for the effects of trait anxiety and depression. Our results provide further support for the role of intolerance of ambiguity in SAD.

  17. Absence of the Gribov ambiguity in a quadratic gauge

    International Nuclear Information System (INIS)

    Raval, Haresh

    2016-01-01

    The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S 3 , when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

  18. Absence of the Gribov ambiguity in a quadratic gauge

    Energy Technology Data Exchange (ETDEWEB)

    Raval, Haresh [Indian Institute of Technology, Bombay, Department of Physics, Mumbai (India)

    2016-05-15

    The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S{sup 3}, when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

  19. Dealing With Uncertainty: Testing Risk- and Ambiguity-Attitude Across Adolescence.

    Science.gov (United States)

    Blankenstein, Neeltje E; Crone, Eveline A; van den Bos, Wouter; van Duijvenvoorde, Anna C K

    2016-01-01

    Attitudes to risk (known probabilities) and attitudes to ambiguity (unknown probabilities) are separate constructs that influence decision making, but their development across adolescence remains elusive. We administered a choice task to a wide adolescent age-range (N = 157, 10-25 years) to disentangle risk- and ambiguity-attitudes using a model-based approach. Additionally, this task was played in a social context, presenting choices from a high risk-taking peer. We observed age-related changes in ambiguity-attitude, but not risk-attitude. Also, ambiguity-aversion was negatively related to real-life risk taking. Finally, the social context influenced only risk-attitudes. These results highlight the importance of disentangling risk- and ambiguity-attitudes in adolescent risk taking.

  20. RELATION OF COACHING BEHAVIOR AND ROLE AMBIGUITY

    Directory of Open Access Journals (Sweden)

    Karamousalidis G.

    2010-08-01

    Full Text Available The purpose of this research was to investigate the relationship between coaching behavior and role ambiguity in defensive responsibilities using interdependent Greek sport teams. Athlete perceptions of role ambiguity (defense were assessed using a questionnaire developed by Beauchamp, Bray, Eys and Carron (2002 andcoaching behavior was assessed using the Coaching Behavior Questionnaire, (Williams, et. al., 2003. The sample consisted of 409 athletes of basketball, volleyball, handball and soccer. Confirmatory factor analysis provided the construct validity of the questionnaires and correlations among the scales confirmed construct validity. The implications of the results are discussed and future research should continue to investigate the multidimensional models of both coaching behavior and role ambiguity in sport settings.

  1. Quantization ambiguity and the Aharanov-Bohm effect

    International Nuclear Information System (INIS)

    Kunstatter, G.

    1983-01-01

    A brief review is given of the role of quantization ambiguity in both quantum mechanics and quantum field theory. The author points out that quantization ambiguity is not relevant to discussions of physical experiments designed to test the Aharanov-Bohm effect. A recent proposal for such an experiment involving Aharanov-Bohm currents in thin superconducting cylinders is mentioned. (Auth.)

  2. Performance management and goal ambiguity: managerial implications in a single payer system.

    Science.gov (United States)

    Calciolari, Stefano; Cantù, Elena; Fattore, Giovanni

    2011-01-01

    Goal ambiguity influences the effectiveness of performance management systems to drive organizations toward enhanced results. The literature analyzes the antecedents of goal ambiguity and shows the influence of goal ambiguity on the performance of U.S. federal agencies. However, no study has analyzed goal ambiguity in other countries or in health care systems. This study has three aims: to test the validity of a measurement instrument for goal ambiguity, to investigate its main antecedents, and to explore the relationship between goal ambiguity and organizational performance in a large, public, Beveridge-type health care system. A nationwide survey of general managers of the Italian national health system was performed. A factor analysis was used to validate the mono-dimensionality of an instrument that measured goal ambiguity. Structural equation modeling was used to test both the antecedents and the influence of goal ambiguity on organizational performance. Data from 135 health care organizations (53% response rate) were available for analysis. The results confirm the mono-dimensionality of the instrument, the existence of two environmental sources of ambiguity (political endorsement and governance commitment), and the negative relationship between goal ambiguity and organizational performance. Goal ambiguity matters because it may hamper organizational performance. Therefore, performance should be fostered by reducing goal ambiguity (e.g., goal-setting model, funding arrangements, and political support). Mutatis mutandis, our results may apply to public health care systems of other countries or other "public interest" sectors, such as social care and education.

  3. Inevitable ambiguity in perturbation around flat space-time

    International Nuclear Information System (INIS)

    Ichinose, S.; Kaminaga, Y.

    1989-01-01

    Perturbation of general-relativistic predictions around flat geometry, in general, introduces inevitable ambiguity. The ambiguity reflects the geometrical nature of general relativity and is never a difficulty of it. We explain it by taking a concrete example of the radar-echo experiment

  4. Hierarchical Morphological Structure and Ambiguity

    DEFF Research Database (Denmark)

    Vikner, Carl; Vikner, Sten

    2008-01-01

    English has a number of adjectives of the type unXable, adjectives that contain the prefix un- and the adjectivising suffix -able, e.g. unlockable or undoable. Many of these adjectives are ambiguous. If a door is unlockable, it may either mean that it cannot be locked (it is not lockable), as exp......English has a number of adjectives of the type unXable, adjectives that contain the prefix un- and the adjectivising suffix -able, e.g. unlockable or undoable. Many of these adjectives are ambiguous. If a door is unlockable, it may either mean that it cannot be locked (it is not lockable...

  5. Removing Ambiguities of IP Telephony Traffic Using Protocol Scrubbers

    Directory of Open Access Journals (Sweden)

    Bazara I. A. Barry

    2012-10-01

    Full Text Available Network intrusion detection systems (NIDSs face the serious challenge of attacks such as insertion and evasion attacks that are caused by ambiguous network traffic. Such ambiguity comes as a result of the nature of network traffic which includes protocol implementation variations and errors alongside legitimate network traffic. Moreover, attackers can intentionally introduce further ambiguities in the traffic. Consequently, NIDSs need to be aware of these ambiguities when detection is performed and make sure to differentiate between true attacks and protocol implementation variations or errors; otherwise, detection accuracy can be affected negatively. In this paper we present the design and implementation of tools that are called protocol scrubbers whose main functionality is to remove ambiguities from network traffic before it is presented to the NIDS. The proposed protocol scrubbers are designed for session initiation and data transfer protocols in IP telephony systems. They guarantee that the traffic presented to NIDSs is unambiguous by eliminating ambiguous behaviors of protocols using well-designed protocol state machines, and walking through packet headers of protocols to make sure packets will be interpreted in the desired way by the NIDS. The experimental results shown in this paper demonstrate the good quality and applicability of the introduced scrubbers.

  6. On the Other Hand : Nondominant Hand Use Increases Sense of Agency

    NARCIS (Netherlands)

    Damen, Tom G. E.; Dijksterhuis, Ap; van Baaren, Rick B.

    In two studies, we investigated the influence of hand dominance on the sense of self-causation or agency. Participants alternately used their dominant or nondominant hand to cause the occurrence of an effect (a tone) in a task in which agency was made ambiguous. Participants were subsequently asked

  7. PENGARUH ROLE AMBIGUITY DAN ROLE CONFLICT TERHADAP KOMITMEN INDEPENDENSI AUDITOR INTERNAL

    Directory of Open Access Journals (Sweden)

    Angga Prasetyo

    2011-05-01

    Full Text Available This study aims to determine the influence of role conflict (role conflict against the commitmentof internal auditors’ independence, and know the effect of role ambiguity (role ambiguity ofthe Internal Auditor independence commitment. Data was collected through primary method byusing a questionnaire. Then performed the data analysis that includes classical assumption test,F test, t test, and analysis of coefficient of determination (R2. To analyze using SPSS softwareversion 16. Based on research result shows that role conflict has a significant negative effect oncommitment to the independence of internal auditors, and role ambiguity (role ambiguity has asignificant negative effect on commitment to the independence of internal auditors. While basedon simultaneous test (F test, role conflict (role conflict and role ambiguity (role ambiguity havean influence on the commitment of internal auditor independence.

  8. Rainbow-shift mechanism behind discrete optical-potential ambiguities

    International Nuclear Information System (INIS)

    Brandan, M.E.; McVoy, K.W.

    1991-01-01

    Some years ago, Drisko et al. suggested that the discrete ambiguity often encountered for elastic scattering optical potentials could be understood as being due to the interior or small-l S-matrix elements for two ''equivalent'' potentials differing in phase by 2π, l-by-l. We point out that the absence of this phase change for peripheral partial waves is equally essential, and suggest that a deeper understanding of the ambiguity may be achieved by viewing it as a consequence of a farside interference between interior and peripheral partial waves. It is this interference which produces the broad ''Airy maxima'' of a nuclear rainbow, and we show that a Drisko-type phase-shift increment δ l →(δ l +π) for low-l phases relative to the high-l ones is exactly what is needed to shift a farside rainbow pattern by one Airy maximum, thus providing an equivalent ''rainbow-shift'' interpretation of the discrete ambiguity. The physical importance of both interpretations lies in the fact that the existence of discrete ambiguities (as well as of nuclear rainbows) is explicit evidence for low-l transparency in nucleus-nucleus collisions. The essential role played by low partial waves explains why peripheral reactions have generally not proven helpful in resolving this ambiguity

  9. Perceived ambiguity as a barrier to intentions to learn genome sequencing results.

    Science.gov (United States)

    Taber, Jennifer M; Klein, William M P; Ferrer, Rebecca A; Han, Paul K J; Lewis, Katie L; Biesecker, Leslie G; Biesecker, Barbara B

    2015-10-01

    Many variants that could be returned from genome sequencing may be perceived as ambiguous-lacking reliability, credibility, or adequacy. Little is known about how perceived ambiguity influences thoughts about sequencing results. Participants (n = 494) in an NIH genome sequencing study completed a baseline survey before sequencing results were available. We examined how perceived ambiguity regarding sequencing results and individual differences in medical ambiguity aversion and tolerance for uncertainty were associated with cognitions and intentions concerning sequencing results. Perceiving sequencing results as more ambiguous was associated with less favorable cognitions about results and lower intentions to learn and share results. Among participants low in tolerance for uncertainty or optimism, greater perceived ambiguity was associated with lower intentions to learn results for non-medically actionable diseases; medical ambiguity aversion did not moderate any associations. Results are consistent with the phenomenon of "ambiguity aversion" and may influence whether people learn and communicate genomic information.

  10. Cognitive Flexibility Supports Preschoolers' Detection of Communicative Ambiguity

    Science.gov (United States)

    Gillis, Randall; Nilsen, Elizabeth S.

    2014-01-01

    To become successful communicators, children must be sensitive to the clarity/ambiguity of language. Significant gains in children's ability to detect communicative ambiguity occur during the early school-age years. However, little is known about the cognitive abilities that support this development. Relations between cognitive flexibility and…

  11. On the ambiguity in relativistic tidal deformability

    Science.gov (United States)

    Gralla, Samuel E.

    2018-04-01

    The LIGO collaboration recently reported the first gravitational-wave constraints on the tidal deformability of neutron stars. I discuss an inherent ambiguity in the notion of relativistic tidal deformability that, while too small to affect the present measurement, may become important in the future. I propose a new way to understand the ambiguity and discuss future prospects for reliably linking observed gravitational waveforms to compact object microphysics.

  12. Relation between nonlinear models and gauge ambiguities

    International Nuclear Information System (INIS)

    Balachandran, A.P.; Ramachandran, R.; Rupertsberger, H.; Skagerstam, B.S.

    1980-01-01

    We show that the solutions of a class of nonlinear models also generate gauge ambiguities in the vacuum sector of Yang-Mills theories. Our results extend known connections between gauge ambiguities and certain nonlinear sigma-models, and clarify the underlying group theory. For many nonlinear models, we also give a simple, intrinsic parametrization of physical fields (which have values in a homogeneous space of a group). (orig.)

  13. Nonlinear Suppression of Range Ambiguity in Pulse Doppler Radar

    National Research Council Canada - National Science Library

    Anderson, Jon

    2001-01-01

    ... ambiguities in Doppler and range. First introduced by Palermo in 1962 using two conjugate LFM pulses, the primary nonlinear suppression objective involves reducing range ambiguity, given the waveform is nominally unambiguous...

  14. Biomedical word sense disambiguation with ontologies and metadata: automation meets accuracy

    Directory of Open Access Journals (Sweden)

    Hakenberg Jörg

    2009-01-01

    Full Text Available Abstract Background Ontology term labels can be ambiguous and have multiple senses. While this is no problem for human annotators, it is a challenge to automated methods, which identify ontology terms in text. Classical approaches to word sense disambiguation use co-occurring words or terms. However, most treat ontologies as simple terminologies, without making use of the ontology structure or the semantic similarity between terms. Another useful source of information for disambiguation are metadata. Here, we systematically compare three approaches to word sense disambiguation, which use ontologies and metadata, respectively. Results The 'Closest Sense' method assumes that the ontology defines multiple senses of the term. It computes the shortest path of co-occurring terms in the document to one of these senses. The 'Term Cooc' method defines a log-odds ratio for co-occurring terms including co-occurrences inferred from the ontology structure. The 'MetaData' approach trains a classifier on metadata. It does not require any ontology, but requires training data, which the other methods do not. To evaluate these approaches we defined a manually curated training corpus of 2600 documents for seven ambiguous terms from the Gene Ontology and MeSH. All approaches over all conditions achieve 80% success rate on average. The 'MetaData' approach performed best with 96%, when trained on high-quality data. Its performance deteriorates as quality of the training data decreases. The 'Term Cooc' approach performs better on Gene Ontology (92% success than on MeSH (73% success as MeSH is not a strict is-a/part-of, but rather a loose is-related-to hierarchy. The 'Closest Sense' approach achieves on average 80% success rate. Conclusion Metadata is valuable for disambiguation, but requires high quality training data. Closest Sense requires no training, but a large, consistently modelled ontology, which are two opposing conditions. Term Cooc achieves greater 90

  15. An Investigation into Ambiguity Tolerance in Iranian Senior EFL Undergraduates

    Science.gov (United States)

    Marzban, Amin; Barati, Hossein; Moinzadeh, Ahmad

    2012-01-01

    The present study aimed to explore how tolerant of ambiguity Iranian EFL learners at university level are and if gender plays a role in this regard. To this end, upon filling in the revised SLTAS scale of ambiguity tolerance 194 male and female Iranian teacher trainees were assigned to three ambiguity tolerance groups; namely, high, moderate and…

  16. Robust portfolio choice with ambiguity and learning about return predictability

    DEFF Research Database (Denmark)

    Larsen, Linda Sandris; Branger, Nicole; Munk, Claus

    2013-01-01

    We analyze the optimal stock-bond portfolio under both learning and ambiguity aversion. Stock returns are predictable by an observable and an unobservable predictor, and the investor has to learn about the latter. Furthermore, the investor is ambiguity-averse and has a preference for investment...... strategies that are robust to model misspecifications. We derive a closed-form solution for the optimal robust investment strategy. We find that both learning and ambiguity aversion impact the level and structure of the optimal stock investment. Suboptimal strategies resulting either from not learning...... or from not considering ambiguity can lead to economically significant losses....

  17. Surgical aspects of ambiguous genitalia associated with congenital ...

    African Journals Online (AJOL)

    Aim The aim of the study was to review the current approach to manage ambiguous genitalia caused by CAH. Methods This was a retrospective study of 30 patientswith CAH and ambiguous genitalia treated over 10 years. Age at presentation, degree of verilization, preoperative diagnostic studies, operative technique, ...

  18. Sensory memory for ambiguous vision.

    Science.gov (United States)

    Pearson, Joel; Brascamp, Jan

    2008-09-01

    In recent years the overlap between visual perception and memory has shed light on our understanding of both. When ambiguous images that normally cause perception to waver unpredictably are presented briefly with intervening blank periods, perception tends to freeze, locking into one interpretation. This indicates that there is a form of memory storage across the blank interval. This memory trace codes low-level characteristics of the stored stimulus. Although a trace is evident after a single perceptual instance, the trace builds over many separate stimulus presentations, indicating a flexible, variable-length time-course. This memory shares important characteristics with priming by non-ambiguous stimuli. Computational models now provide a framework to interpret many empirical observations.

  19. Ambiguity resolution in systems using Omega for position location

    Science.gov (United States)

    Frenkel, G.; Gan, D. G.

    1974-01-01

    The lane ambiguity problem prevents the utilization of the Omega system for many applications such as locating buoys and balloons. The method of multiple lines of position introduced herein uses signals from four or more Omega stations for ambiguity resolution. The coordinates of the candidate points are determined first through the use of the Newton iterative procedure. Subsequently, a likelihood function is generated for each point, and the ambiguity is resolved by selecting the most likely point. The method was tested through simulation.

  20. A Lexical Analysis Tool with Ambiguity Support

    OpenAIRE

    Quesada, Luis; Berzal, Fernando; Cortijo, Francisco J.

    2012-01-01

    Lexical ambiguities naturally arise in languages. We present Lamb, a lexical analyzer that produces a lexical analysis graph describing all the possible sequences of tokens that can be found within the input string. Parsers can process such lexical analysis graphs and discard any sequence of tokens that does not produce a valid syntactic sentence, therefore performing, together with Lamb, a context-sensitive lexical analysis in lexically-ambiguous language specifications.

  1. De morseir syndrome presenting as ambiguous genitalia

    OpenAIRE

    Anubhav Thukral; S Chitra; Partho P Chakraborty; Ajitesh Roy; Soumik Goswami; Rana Bhattacharjee; Deep Dutta; Indira Maisnam; Sujoy Ghosh; Satinath Mukherjee; Subhankar Chowdhury

    2012-01-01

    Background: A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. Materials and Methods: The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficie...

  2. Betwixt and between: Role conflict, role ambiguity and role definition in project-based dual-leadership structures

    Science.gov (United States)

    Ebbers, Joris J; Wijnberg, Nachoem M

    2017-01-01

    Project-based organizations in the film industry usually have a dual-leadership structure, based on a division of tasks between the dual leaders – the director and the producer – in which the former is predominantly responsible for the artistic and the latter for the commercial aspects of the film. These organizations also have a role hierarchically below and between the dual leaders: the 1st assistant director. This organizational constellation is likely to lead to role conflict and role ambiguity experienced by the person occupying that particular role. Although prior studies found negative effects of role conflict and role ambiguity, this study shows they can also have beneficial effects because they create space for defining the role expansively that, in turn, can be facilitated by the dual leaders defining their own roles more narrowly. In a more general sense, this study also shows the usefulness of analyzing the antecedents and consequences of roles, role definition, and role crafting in connection to the behavior of occupants of adjacent roles. PMID:29081536

  3. Decision ambiguity is mediated by a late positive potential originating from cingulate cortex.

    Science.gov (United States)

    Sun, Sai; Zhen, Shanshan; Fu, Zhongzheng; Wu, Daw-An; Shimojo, Shinsuke; Adolphs, Ralph; Yu, Rongjun; Wang, Shuo

    2017-08-15

    People often make decisions in the face of ambiguous information, but it remains unclear how ambiguity is represented in the brain. We used three types of ambiguous stimuli and combined EEG and fMRI to examine the neural representation of perceptual decisions under ambiguity. We identified a late positive potential, the LPP, which differentiated levels of ambiguity, and which was specifically associated with behavioral judgments about choices that were ambiguous, rather than passive perception of ambiguous stimuli. Mediation analyses together with two further control experiments confirmed that the LPP was generated only when decisions are made (not during mere perception of ambiguous stimuli), and only when those decisions involved choices on a dimension that is ambiguous. A further control experiment showed that a stronger LPP arose in the presence of ambiguous stimuli compared to when only unambiguous stimuli were present. Source modeling suggested that the LPP originated from multiple loci in cingulate cortex, a finding we further confirmed using fMRI and fMRI-guided ERP source prediction. Taken together, our findings argue for a role of an LPP originating from cingulate cortex in encoding decisions based on task-relevant perceptual ambiguity, a process that may in turn influence confidence judgment, response conflict, and error correction. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Ambiguity tolerance in organizations: definitional clarification and perspectives on future research.

    Science.gov (United States)

    McLain, David L; Kefallonitis, Efstathios; Armani, Kimberly

    2015-01-01

    Ambiguity tolerance is an increasingly popular subject for study in a wide variety of fields. The definition of ambiguity tolerance has changed since its inception, and accompanying that change are changes in measurement and the research questions that interest researchers. There is a wealth of opportunity for research related to ambiguity tolerance and recent advances in neuroscience, measurement, trait research, perception, problem solving, and other fields highlight areas of interest and point to issues that need further attention. The future of ambiguity tolerance research is promising and it is expected that future studies will yield new insights into individual differences in reactions to the complex, unfamiliar, confusing, indeterminate, and incomplete stimuli that fall within the conceptual domain of ambiguity.

  5. Finding meaning in art: Preferred levels of ambiguity in art appreciation

    Science.gov (United States)

    Jakesch, Martina; Leder, Helmut

    2011-01-01

    Uncertainty is typically not desirable in everyday experiences, but uncertainty in the form of ambiguity may be a defining feature of aesthetic experiences of modern art. In this study, we examined different hypotheses concerning the quantity and quality of information appreciated in art. Artworks were shown together with auditorily presented statements. We tested whether the amount of information, the amount of matching information, or the proportion of matching to nonmatching statements apparent in a picture (levels of ambiguity) affect liking and interestingness. Only the levels of ambiguity predicted differences in the two dependent variables. These findings reveal that ambiguity is an important determinant of aesthetic appreciation and that a certain level of ambiguity is appreciable. PMID:19565431

  6. Children's Comprehension of Two Types of Syntactic Ambiguity

    Science.gov (United States)

    Zimmer, Elly Jane

    2017-01-01

    This study asks whether children accept both interpretations of ambiguous sentences with contexts supporting each option. Twenty-six 3- to 5-year-old English-speaking children and a control group of 30 English-speaking adults participated in a truth value judgment task. As a step towards evaluating the complexity of syntactic ambiguity, the…

  7. Ambiguous sets of partial wave amplitudes can intersect

    International Nuclear Information System (INIS)

    Kok, L.P.; Roo, M. de

    1976-01-01

    Continuation in energy as a method to resolve ambiguities in phase-shift analysis is discussed. It is shown that continuity in energy is not in all cases sufficient to resolve ambiguities, and examples are given of such cases for both spin 0 - spin 0 and spin 0 - spin 1/2 scattering. (author)

  8. Development of a New Scale to Measure Ambiguity Tolerance in Veterinary Students.

    Science.gov (United States)

    Hammond, Jennifer A; Hancock, Jason; Martin, Margaret S; Jamieson, Susan; Mellor, Dominic J

    The ability to cope with ambiguity and feelings of uncertainty is an essential part of professional practice. Research with physicians has identified that intolerance of ambiguity or uncertainty is linked to stress, and some authors have hypothesized that there could be an association between intolerance of ambiguity and burnout. We describe the adaptation of the TAMSAD (Tolerance of Ambiguity in Medical Students and Doctors) scale for use with veterinary students. Exploratory factor analysis supports a uni-dimensional structure for the Ambiguity tolerance construct. Although internal reliability of the 29-item TAMSAD scale is reasonable (α=.50), an alternative 27-item scale (drawn from the original 41 items used to develop TAMSAD) shows higher internal reliability for veterinary students (α=.67). We conclude that there is good evidence to support the validity of this latter TAVS (Tolerance of Ambiguity in Veterinary Students) scale to study ambiguity tolerance in veterinary students.

  9. An ambiguity in one-loop quantum gravity

    International Nuclear Information System (INIS)

    Capper, D.M.; Kimber, D.P.

    1980-01-01

    It is argued that the application of the dimensional regularisation technique to one-loop quantum gravity calculations is ambiguous. However, for the calculation of on-mass-shell S-matrix elements, this ambiguity can be resolved by requiring consistency with results obtained from other regularisation schemes. Some discussion is also given of the implications of this work for recent attempts to use higher derivative Lagrangians to solve the renormalisability problem in quantum gravity. (author)

  10. Generalized dynamic model and control of ambiguous mono axial vehicle robot

    Directory of Open Access Journals (Sweden)

    Frantisek Duchon

    2016-09-01

    Full Text Available This article deals with the novel concept of ambiguous mono axial vehicle robot. Such robot is a combination of Segway and dicycle, which utilizes the advantages of each chassis. The advantage of dicycle is lower energy consumption during the movement and the higher safety of carried payload. The movable platform inside the ambiguous mono axial vehicle allows using the various sensors or devices. This will change the ambiguous mono axial vehicle to the Segway type robot. Both these modes are necessary to control in the stable mode to ensure the safety of the ambiguous mono axial vehicle’s movement. The main contents of the article contain description of generalized dynamic model of ambiguous mono axial vehicle and related control of ambiguous mono axial vehicle. The proposal is unique in that the same controller is used for both modes. Several simulations verify proposed control schemes and identified parameters. Moreover, the dicycle type of platform has never been used in robotics and that is another novelty.

  11. Scheme-scale ambiguity in analysis of QCD observable

    International Nuclear Information System (INIS)

    Mirjalili, A.; Kniehl, B.A.

    2010-01-01

    The scheme-scale ambiguity that has plagued perturbative analysis in QCD remains on obstacle to making precise tests of the theory. Many attempts have been done to resolve the scale ambiguity. In this regard the BLM, EC, PMS and CORGI approaches are more distinct. We try to employ these methods to fix the scale ambiguity at NLO, NNLO and even in more higher order approximations. By optimizing the renormalization scale, there will be a possibility to predicate higher order terms. We present general results for predicted terms at any order, using different optimization methods. Some observable as specific examples will be used to indicate the validity of scale fixing to predicate the higher order terms. (authors)

  12. Renormalization ambiguities and conformal anomaly in metric-scalar backgrounds

    International Nuclear Information System (INIS)

    Asorey, M.; Berredo-Peixoto, G. de; Shapiro, I. L.

    2006-01-01

    We analyze the problem of the existing ambiguities in the conformal anomaly in theories with an external scalar field in curved backgrounds. In particular, we consider the anomaly of a self-interacting massive scalar field theory and of a Yukawa model in the massless conformal limit. In all cases the ambiguities are related to finite renormalizations of local nonminimal terms in the effective action. We point out the generic nature of this phenomenon and provide a general method to identify the theories where such an ambiguity can arise

  13. Functionally distinct contributions of the anterior and posterior putamen during sublexical and lexical reading

    Directory of Open Access Journals (Sweden)

    Marion eOberhuber

    2013-11-01

    Full Text Available Previous studies have investigated orthographic-to-phonological mapping during reading by comparing brain activation for (1 reading words to object naming, or (2 reading pseudowords (e.g. phume to words (e.g. plume. Here we combined both approaches to provide new insights into the underlying neural mechanisms. In fMRI data from 25 healthy adult readers, we first identified activation that was greater for reading words and pseudowords relative to picture and color naming. The most significant effect was observed in the left putamen, extending to both anterior and posterior borders. Second, consistent with previous studies, we show that both the anterior and posterior putamen are involved in articulating speech with greater activation during our overt speech production tasks (reading, repetition, object naming and color naming than silent one-back-matching on the same stimuli. Third, we compared putamen activation for words versus pseudowords during overt reading and auditory repetition. This revealed that the anterior putamen was most activated by reading pseudowords, whereas the posterior putamen was most activated by words irrespective of whether the task was reading words or auditory word repetition. The pseudoword effect in the anterior putamen is consistent with prior studies that associated this region with the initiation of novel sequences of movements. In contrast, the heightened word response in the posterior putamen is consistent with other studies that associated this region with memory guided movement. Our results illustrate how the functional dissociation between the anterior and posterior putamen supports sublexical and lexical processing during reading.

  14. A method of undifferenced ambiguity resolution for GPS+GLONASS precise point positioning.

    Science.gov (United States)

    Yi, Wenting; Song, Weiwei; Lou, Yidong; Shi, Chuang; Yao, Yibin

    2016-05-25

    Integer ambiguity resolution is critical for achieving positions of high precision and for shortening the convergence time of precise point positioning (PPP). However, GLONASS adopts the signal processing technology of frequency division multiple access and results in inter-frequency code biases (IFCBs), which are currently difficult to correct. This bias makes the methods proposed for GPS ambiguity fixing unsuitable for GLONASS. To realize undifferenced GLONASS ambiguity fixing, we propose an undifferenced ambiguity resolution method for GPS+GLONASS PPP, which considers the IFCBs estimation. The experimental result demonstrates that the success rate of GLONASS ambiguity fixing can reach 75% through the proposed method. Compared with the ambiguity float solutions, the positioning accuracies of ambiguity-fixed solutions of GLONASS-only PPP are increased by 12.2%, 20.9%, and 10.3%, and that of the GPS+GLONASS PPP by 13.0%, 35.2%, and 14.1% in the North, East and Up directions, respectively.

  15. Ambiguity and Investment Decisions: An Empirical Analysis on Mutual Fund Investor Behaviour

    Directory of Open Access Journals (Sweden)

    Chao Tang

    2017-09-01

    Full Text Available The paper empirically studies the relationship between ambiguity and mutual fund investor behaviour. Theoretical models for investment decisions incorporating ambiguity motivate our analyses. While the models indicate that investors would less likely to invest in financial markets when ambiguity increases, there is rare empirical evidence in natural occurring financial data to examine this hypothesis. In this paper, we test the hypothesis with equity fund flow data as for investment decisions and ambiguity with the degree of disagreement in equity analysts’ prediction about asset returns. Our results support the hypothesis that increases in ambiguity could lead to less fund flows and this result remains consistently when adding various control variables affecting fund flows. Besides, we find that heterogeneous impacts of ambiguity: equity funds with high yield targets and active management style are affected more than funds investing in stable stocks; funds with larger proportion of institutional investors are more sensitive and affected by the ambiguity.

  16. Ambiguities of the phase analysis of the proton-proton scattering amplitude

    International Nuclear Information System (INIS)

    Grebenyuk, O.G.; Shklyarevskij, G.M.

    1980-01-01

    Ambiguities of the phase analysis of the proton-proton scattering amplitude are analysed. It is shown that for five measurements of polarization parameters sets there are ambiguities similar to the Gersten ambiguities in the phase analysis of πN scattering. A problem on additional experiments needed to eliminate these ambiguities is investigated. It is shown that for this purpose it suffices to measure three total cross sections with polarized and nonpolarized protons, thus determining the imaginary parts of amplitudes at THETA=0 and polarization parameters

  17. Ambiguity Tolerance in Organizations: Definitional Clarification and Perspectives on Future Research

    Directory of Open Access Journals (Sweden)

    David L Mclain

    2015-04-01

    Full Text Available Ambiguity tolerance is an increasingly popular subject for study in a wide variety of fields. The definition of ambiguity tolerance has changed since its inception, and accompanying that change are changes in measurement and the research questions that interest researchers. There is a wealth of opportunity for research related to ambiguity tolerance and recent advances in neuroscience, measurement, trait research, perception, problem solving, and other fields highlight areas of interest and point to issues that need further attention. The future of ambiguity tolerance research is promising and it is expected that future studies will yield new insights into individual differences in reactions to the complex, unfamiliar, confusing, indeterminate, and incomplete stimuli that fall within the conceptual domain of ambiguity.

  18. Ambiguity in urban belonging

    DEFF Research Database (Denmark)

    Koefoed, Lasse Martin; Simonsen, Kirsten

    2015-01-01

    mapping of life as an ethnic minority in the city. It revolves around three issues. First, it focuses on the narrators’ experiences of exclusions and blockages in everyday life. This is followed by a focus on urban belonging emphasizing its differential character. Finally, the ambiguity of experiences...

  19. Crichton's phase-shift ambiguity

    NARCIS (Netherlands)

    Atkinson, D.; Johnson, P.W.; Mehta, N.; Roo, M. de

    1973-01-01

    A re-examination of the SPD phase-shift ambiguity is made with a view to understanding certain singular features of the elastic unitarity constraint. An explicit solution of Crichton's equations is presented, and certain features of this solution are displayed graphically. In particular, it is shown

  20. Ambiguity and Nominal Group Multiple Post modification in the ...

    African Journals Online (AJOL)

    Administrator

    students of The Federal Polytechnic, Ede, Nigeria offering. English courses as .... “a piece of land along a river” or “a place for keeping money and valuables”. ... ambiguity. Attachment ambiguity occurs when a modifier may be logically or ...

  1. Ambiguity of non-systematic chemical identifiers within and between small-molecule databases.

    Science.gov (United States)

    Akhondi, Saber A; Muresan, Sorel; Williams, Antony J; Kors, Jan A

    2015-01-01

    A wide range of chemical compound databases are currently available for pharmaceutical research. To retrieve compound information, including structures, researchers can query these chemical databases using non-systematic identifiers. These are source-dependent identifiers (e.g., brand names, generic names), which are usually assigned to the compound at the point of registration. The correctness of non-systematic identifiers (i.e., whether an identifier matches the associated structure) can only be assessed manually, which is cumbersome, but it is possible to automatically check their ambiguity (i.e., whether an identifier matches more than one structure). In this study we have quantified the ambiguity of non-systematic identifiers within and between eight widely used chemical databases. We also studied the effect of chemical structure standardization on reducing the ambiguity of non-systematic identifiers. The ambiguity of non-systematic identifiers within databases varied from 0.1 to 15.2 % (median 2.5 %). Standardization reduced the ambiguity only to a small extent for most databases. A wide range of ambiguity existed for non-systematic identifiers that are shared between databases (17.7-60.2 %, median of 40.3 %). Removing stereochemistry information provided the largest reduction in ambiguity across databases (median reduction 13.7 percentage points). Ambiguity of non-systematic identifiers within chemical databases is generally low, but ambiguity of non-systematic identifiers that are shared between databases, is high. Chemical structure standardization reduces the ambiguity to a limited extent. Our findings can help to improve database integration, curation, and maintenance.

  2. Evaluating cognitive models of visual word recognition using fMRI: Effects of lexical and sublexical variables.

    Science.gov (United States)

    Protopapas, Athanassios; Orfanidou, Eleni; Taylor, J S H; Karavasilis, Efstratios; Kapnoula, Efthymia C; Panagiotaropoulou, Georgia; Velonakis, Georgios; Poulou, Loukia S; Smyrnis, Nikolaos; Kelekis, Dimitrios

    2016-03-01

    In this study predictions of the dual-route cascaded (DRC) model of word reading were tested using fMRI. Specifically, patterns of co-localization were investigated: (a) between pseudoword length effects and a pseudowords vs. fixation contrast, to reveal the sublexical grapho-phonemic conversion (GPC) system; and (b) between word frequency effects and a words vs. pseudowords contrast, to reveal the orthographic and phonological lexicon. Forty four native speakers of Greek were scanned at 3T in an event-related lexical decision task with three event types: (a) 150 words in which frequency, length, bigram and syllable frequency, neighborhood, and orthographic consistency were decorrelated; (b) 150 matched pseudowords; and (c) fixation. Whole-brain analysis failed to reveal the predicted co-localizations. Further analysis with participant-specific regions of interest defined within masks from the group contrasts revealed length effects in left inferior parietal cortex and frequency effects in the left middle temporal gyrus. These findings could be interpreted as partially consistent with the existence of the GPC system and phonological lexicon of the model, respectively. However, there was no evidence in support of an orthographic lexicon, weakening overall support for the model. The results are discussed with respect to the prospect of using neuroimaging in cognitive model evaluation. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Good luck, bad luck, and ambiguity aversion

    OpenAIRE

    Briony D. Pulford; Poonam Gill

    2014-01-01

    We report a series of experiments investigating the influence of feeling lucky or unlucky on people's choice of known-risk or ambiguous options using the traditional Ellsberg Urns decision-making task. We induced a state of feeling lucky or unlucky in subjects by using a rigged wheel-of-fortune game, which just missed either the bankrupt or the jackpot outcome. In the first experiment a large reversal of the usual ambiguity aversion effect was shown, indicating that feeling ...

  4. Quantization ambiguity and non-trivial vacuum structure

    International Nuclear Information System (INIS)

    Rothe, H.J.; Swieca, J.A.

    1978-01-01

    It is pointed out that there is an ambiguity in quantization of any system whose configuration space has a non-trivial topology characterized by a Chern number. In field theories this ambiguity manifests itself through the existence of theta-sectors. The point of view adopted gives a simple interpretation of the difference between the temporal and Coulomb gauge descriptions of instantons. The general ideas are exemplified in the O(3) non-linear sigma-model in two dimensions [pt

  5. Making sense of global warming: Norwegians appropriating knowledge of anthropogenic climate change.

    Science.gov (United States)

    Ryghaug, Marianne; Sørensen, Knut Holtan; Naess, Robert

    2011-11-01

    This paper studies how people reason about and make sense of human-made global warming, based on ten focus group interviews with Norwegian citizens. It shows that the domestication of climate science knowledge was shaped through five sense-making devices: news media coverage of changes in nature, particularly the weather, the coverage of presumed experts' disagreement about global warming, critical attitudes towards media, observations of political inaction, and considerations with respect to everyday life. These sense-making devices allowed for ambiguous outcomes, and the paper argues four main outcomes with respect to the domestication processes: the acceptors, the tempered acceptors, the uncertain and the sceptics.

  6. Attitudes toward risk and ambiguity in patients with autism spectrum disorder.

    Science.gov (United States)

    Fujino, Junya; Tei, Shisei; Hashimoto, Ryu-Ichiro; Itahashi, Takashi; Ohta, Haruhisa; Kanai, Chieko; Okada, Rieko; Kubota, Manabu; Nakamura, Motoaki; Kato, Nobumasa; Takahashi, Hidehiko

    2017-01-01

    Although the ability to make optimal decisions under uncertainty is an integral part of everyday life, individuals with autism spectrum disorder (ASD) frequently report that they experience difficulties with this skill. In behavioral economics, researchers distinguish two types of uncertainty to understand decision-making in this setting: risk (known probabilities) and ambiguity (unknown probabilities). However, it remains unclear how individuals with ASD behave under risk and ambiguity, despite growing evidence of their altered decision-making under uncertainty. We therefore extended previous research by studying the attitudes of those with ASD toward risk and ambiguity in both positive and negative contexts (i.e., gain and loss). In gain contexts, no significant difference was observed between the groups in risk attitudes, but ambiguity aversion was attenuated in ASD. In loss contexts, ambiguity attitudes did not significantly differ between the groups, but the ASD participants were less risk-seeking compared with the controls. In addition, insensitivity to the context change under risk and ambiguity in ASD was both significantly associated with poor social skills. These results improve our understanding of altered decision-making under uncertainty by disentangling the attitudes toward risk and ambiguity in ASD individuals. Applying behavioral economic tools may provide insights into the mechanisms underlying behavioral disturbances in ASD.

  7. Computational Humour : Utilizing Cross-Reference Ambiguity for Conversational Jokes

    NARCIS (Netherlands)

    Tinholt, Hans Wim; Nijholt, Anton; Masulli, Francesco; Mitra, Sushmita; Pasi, Gabriella

    2007-01-01

    This paper presents a computer implementation that utilizes cross-reference ambiguity in utterances for simple conversational jokes. The approach is based on the SSTH. Using a simple script representation, it is shown that cross-reference ambiguities always satisfy the SSTH requirement for script

  8. Roles of frontal and temporal regions in reinterpreting semantically ambiguous sentences

    Directory of Open Access Journals (Sweden)

    Sylvia eVitello

    2014-07-01

    Full Text Available Semantic ambiguity resolution is an essential and frequent part of speech comprehension because many words map onto multiple meanings (e.g., bark, bank. Neuroimaging research highlights the importance of the left inferior frontal gyrus (LIFG and the left posterior temporal cortex in this process but the roles they serve in ambiguity resolution are uncertain. One possibility is that both regions are engaged in the processes of semantic reinterpretation that follows incorrect interpretation of an ambiguous word. Here we used fMRI to investigate this hypothesis. 20 native British English monolinguals were scanned whilst listening to sentences that contained an ambiguous word. To induce semantic reinterpretation, the disambiguating information was presented after the ambiguous word and delayed until the end of the sentence (e.g., the teacher explained that the BARK was going to be very damp. These sentences were compared to well-matched unambiguous sentences. Supporting the reinterpretation hypothesis, these ambiguous sentences produced more activation in both the LIFG and the left posterior inferior temporal cortex. Importantly, all but one subject showed ambiguity-related peaks within both regions, demonstrating that the group-level results were driven by high inter-subject consistency. Further support came from the finding that activation in both regions was modulated by meaning dominance. Specifically, sentences containing biased ambiguous words, which have one more dominant meaning, produced greater activation than those with balanced ambiguous words, which have two equally frequent meanings. Because the context always supported the less frequent meaning, the biased words require reinterpretation more often than balanced words. This is the first evidence of dominance effects in the spoken modality and provides strong support that frontal and temporal regions support the updating of semantic representations during speech comprehension.

  9. The Learning Teacher: Role of Ambiguity in Education

    Science.gov (United States)

    Suzawa, Gilbert S.

    2013-01-01

    Life is full of ambiguities, but as teachers we generally try to teach our students in a manner that sanitizes knowledge of all of its ambiguities. In doing so, we create an educational environment which forces students to learn in a rather meaningless fashion and this in turn leads to a lack of vitality and relevance within the academy. This need…

  10. Attitude Toward Ambiguity: Empirically Robust Factors in Self-Report Personality Scales.

    Science.gov (United States)

    Lauriola, Marco; Foschi, Renato; Mosca, Oriana; Weller, Joshua

    2016-06-01

    Two studies were conducted to examine the factor structure of attitude toward ambiguity, a broad personality construct that refers to personal reactions to perceived ambiguous stimuli in a variety of context and situations. Using samples from two countries, Study 1 mapped the hierarchical structure of 133 items from seven tolerance-intolerance of ambiguity scales (N = 360, Italy; N = 306, United States). Three major factors-Discomfort with Ambiguity, Moral Absolutism/Splitting, and Need for Complexity and Novelty-were recovered in each country with high replicability coefficients across samples. In Study 2 (N = 405, Italian community sample; N =366, English native speakers sample), we carried out a confirmatory analysis on selected factor markers. A bifactor model had an acceptable fit for each sample and reached the construct-level invariance for general and group factors. Convergent validity with related traits was assessed in both studies. We conclude that attitude toward ambiguity can be best represented a multidimensional construct involving affective (Discomfort with Ambiguity), cognitive (Moral Absolutism/Splitting), and epistemic (Need for Complexity and Novelty) components. © The Author(s) 2015.

  11. Semantic ambiguity effects on traditional Chinese character naming: A corpus-based approach.

    Science.gov (United States)

    Chang, Ya-Ning; Lee, Chia-Ying

    2017-11-09

    Words are considered semantically ambiguous if they have more than one meaning and can be used in multiple contexts. A number of recent studies have provided objective ambiguity measures by using a corpus-based approach and have demonstrated ambiguity advantages in both naming and lexical decision tasks. Although the predictive power of objective ambiguity measures has been examined in several alphabetic language systems, the effects in logographic languages remain unclear. Moreover, most ambiguity measures do not explicitly address how the various contexts associated with a given word relate to each other. To explore these issues, we computed the contextual diversity (Adelman, Brown, & Quesada, Psychological Science, 17; 814-823, 2006) and semantic ambiguity (Hoffman, Lambon Ralph, & Rogers, Behavior Research Methods, 45; 718-730, 2013) of traditional Chinese single-character words based on the Academia Sinica Balanced Corpus, where contextual diversity was used to evaluate the present semantic space. We then derived a novel ambiguity measure, namely semantic variability, by computing the distance properties of the distinct clusters grouped by the contexts that contained a given word. We demonstrated that semantic variability was superior to semantic diversity in accounting for the variance in naming response times, suggesting that considering the substructure of the various contexts associated with a given word can provide a relatively fine scale of ambiguity information for a word. All of the context and ambiguity measures for 2,418 Chinese single-character words are provided as supplementary materials.

  12. A method to reduce ambiguities of qualitative reasoning for conceptual design applications

    NARCIS (Netherlands)

    D'Amelio, V.; Chmarra, M.K.; Tomiyama, T.

    2013-01-01

    Qualitative reasoning can generate ambiguous behaviors due to the lack of quantitative information. Despite many different research results focusing on ambiguities reduction, fundamentally it is impossible to totally remove ambiguities with only qualitative methods and to guarantee the consistency

  13. Ambiguous Loss in a Non-Western Context: Families of the Disappeared in Postconflict Nepal

    Science.gov (United States)

    Robins, Simon

    2010-01-01

    Ambiguous loss has become a standard theory for understanding the impact of situations where the presence of a family member is subject to ambiguity. A number of studies of ambiguous loss have been made in a range of situations of ambiguity, but almost all have been firmly located within a Western cultural context. Here, ambiguous loss is explored…

  14. SAR Cross-Ambiguities in SAOCOM-CS Large Baseline Bistatic Configuration

    OpenAIRE

    Bordoni, Federica; Rodriguez-Cassola, Marc; Younis, Marwan; Prats-Iraola, Pau; Lopez-Dekker, Paco; Krieger, Gerhard

    2016-01-01

    The evaluation of the ambiguous signal level, the Ambiguity-to-Signal Ratio (ASR), plays a key role in the Synthetic Aperture Radar (SAR) design and performance prediction. In conventional SAR acquisition scenarios, the computation of the ASR is based on the evaluation of the range and azimuth ambiguous contributes. Though appealing for its simplicity, this approach could be inaccurate in case of complex SAR acquisition geometries. In this paper we focus on the ASR performance of the SAOCOM-...

  15. De morseir syndrome presenting as ambiguous genitalia

    Directory of Open Access Journals (Sweden)

    Anubhav Thukral

    2012-01-01

    Full Text Available Background: A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. Materials and Methods: The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficient as suggested by auxology, low IGF1, and poor response to clonidine stimulation. MRI brain shows hypoplastic corpus callosum, hypoplastic anterior pituitary, and ectopic posterior pituitary bright spot. Results: The patient underwent laparoscopic removal of right intrabdominal testis and orchidoplexy was performed on the left one. Testicular biopsy revealed no malignancy and growth hormone replacement was initiated. The patient awaits definitive repair of hypospadias. Conclusion: As a provisional diagnosis of combined growth hormone and gonadotropin deficiency, most probable diagnosis is septo-optic dysplasia or de moseir syndrome leading to genital ambiguity.

  16. De morseir syndrome presenting as ambiguous genitalia.

    Science.gov (United States)

    Thukral, Anubhav; Chitra, S; Chakraborty, Partho P; Roy, Ajitesh; Goswami, Soumik; Bhattacharjee, Rana; Dutta, Deep; Maisnam, Indira; Ghosh, Sujoy; Mukherjee, Satinath; Chowdhury, Subhankar

    2012-12-01

    A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficient as suggested by auxology, low IGF1, and poor response to clonidine stimulation. MRI brain shows hypoplastic corpus callosum, hypoplastic anterior pituitary, and ectopic posterior pituitary bright spot. The patient underwent laparoscopic removal of right intrabdominal testis and orchidoplexy was performed on the left one. Testicular biopsy revealed no malignancy and growth hormone replacement was initiated. The patient awaits definitive repair of hypospadias. As a provisional diagnosis of combined growth hormone and gonadotropin deficiency, most probable diagnosis is septo-optic dysplasia or de moseir syndrome leading to genital ambiguity.

  17. Discriminating Between Models of Ambiguity Attitude : A Qualitative Test

    NARCIS (Netherlands)

    Cubitt, Robin; van de Kuilen, Gijs; Mukerji, Sujoy

    The exchange between Epstein (2010) and Klibanoff et al. (2012) identified a behavioral issue that sharply distinguishes between two classes of models of ambiguity sensitivity, exemplified by the 훼- MEU model and the smooth ambiguity model, respectively. The issue in question is whether a subject’s

  18. Neural responses to ambiguity involve domain-general and domain-specific emotion processing systems.

    Science.gov (United States)

    Neta, Maital; Kelley, William M; Whalen, Paul J

    2013-04-01

    Extant research has examined the process of decision making under uncertainty, specifically in situations of ambiguity. However, much of this work has been conducted in the context of semantic and low-level visual processing. An open question is whether ambiguity in social signals (e.g., emotional facial expressions) is processed similarly or whether a unique set of processors come on-line to resolve ambiguity in a social context. Our work has examined ambiguity using surprised facial expressions, as they have predicted both positive and negative outcomes in the past. Specifically, whereas some people tended to interpret surprise as negatively valenced, others tended toward a more positive interpretation. Here, we examined neural responses to social ambiguity using faces (surprise) and nonface emotional scenes (International Affective Picture System). Moreover, we examined whether these effects are specific to ambiguity resolution (i.e., judgments about the ambiguity) or whether similar effects would be demonstrated for incidental judgments (e.g., nonvalence judgments about ambiguously valenced stimuli). We found that a distinct task control (i.e., cingulo-opercular) network was more active when resolving ambiguity. We also found that activity in the ventral amygdala was greater to faces and scenes that were rated explicitly along the dimension of valence, consistent with findings that the ventral amygdala tracks valence. Taken together, there is a complex neural architecture that supports decision making in the presence of ambiguity: (a) a core set of cortical structures engaged for explicit ambiguity processing across stimulus boundaries and (b) other dedicated circuits for biologically relevant learning situations involving faces.

  19. Resolution of ambiguities in perturbative QCD

    International Nuclear Information System (INIS)

    Nakkagawa, Hisao; Niegawa, Akira.

    1984-01-01

    In the perturbative QCD analyses of the deeply inelastic processes, the coupling constant depends on at least two mass-scales, the renormalization scale and the factorization scale. By integrating the coupled renormalization group equations with respect to these two mass-scales, the running coupling constant is defined. A perturbative approximation then introduces a new ambiguity, the integration-path dependence, into the theory. We show that the problem of this new ambiguity is resolved by imposing Stevenson's principle of minimal sensitivity. Together with the analogous analysis of the operator matrix element or the cut vertex, we can completely solve the problem of getting an unambiguous perturbative QCD prediction. (author)

  20. Increasing Statistical Literacy by Exploiting Lexical Ambiguity of Technical Terms

    Directory of Open Access Journals (Sweden)

    Jennifer Kaplan

    2018-01-01

    Full Text Available Instructional inattention to language poses a barrier for students in entry-level science courses, in part because students may perceive a subject as difficult solely based on the lack of understanding of the vocabulary. In addition, the technical use of terms that have different everyday meanings may cause students to misinterpret statements made by instructors, leading to an incomplete or incorrect understanding of the domain. Terms that have different technical and everyday meanings are said to have lexical ambiguity and statistics, as a discipline, has many lexically ambiguous terms. This paper presents a cyclic process for designing activities to address lexical ambiguity in statistics. In addition, it describes three short activities aimed to have high impact on student learning associated with two different lexically ambiguous words or word pairs in statistics. Preliminary student-level data are used to assess the efficacy of the activities, and future directions for development of activities and research about lexical ambiguity in statistics in particular and STEM in general are discussed.

  1. Neural correlates of sublexical processing in phonological working memory.

    Science.gov (United States)

    McGettigan, Carolyn; Warren, Jane E; Eisner, Frank; Marshall, Chloe R; Shanmugalingam, Pradheep; Scott, Sophie K

    2011-04-01

    This study investigated links between working memory and speech processing systems. We used delayed pseudoword repetition in fMRI to investigate the neural correlates of sublexical structure in phonological working memory (pWM). We orthogonally varied the number of syllables and consonant clusters in auditory pseudowords and measured the neural responses to these manipulations under conditions of covert rehearsal (Experiment 1). A left-dominant network of temporal and motor cortex showed increased activity for longer items, with motor cortex only showing greater activity concomitant with adding consonant clusters. An individual-differences analysis revealed a significant positive relationship between activity in the angular gyrus and the hippocampus, and accuracy on pseudoword repetition. As models of pWM stipulate that its neural correlates should be activated during both perception and production/rehearsal [Buchsbaum, B. R., & D'Esposito, M. The search for the phonological store: From loop to convolution. Journal of Cognitive Neuroscience, 20, 762-778, 2008; Jacquemot, C., & Scott, S. K. What is the relationship between phonological short-term memory and speech processing? Trends in Cognitive Sciences, 10, 480-486, 2006; Baddeley, A. D., & Hitch, G. Working memory. In G. H. Bower (Ed.), The psychology of learning and motivation: Advances in research and theory (Vol. 8, pp. 47-89). New York: Academic Press, 1974], we further assessed the effects of the two factors in a separate passive listening experiment (Experiment 2). In this experiment, the effect of the number of syllables was concentrated in posterior-medial regions of the supratemporal plane bilaterally, although there was no evidence of a significant response to added clusters. Taken together, the results identify the planum temporale as a key region in pWM; within this region, representations are likely to take the form of auditory or audiomotor "templates" or "chunks" at the level of the syllable

  2. Preferences for 'New' Treatments Diminish in the Face of Ambiguity.

    Science.gov (United States)

    Harrison, Mark; Marra, Carlo A; Bansback, Nick

    2017-06-01

    New products usually offer advantages over existing products, but in health care, most new drugs are 'me-too', comparable in effectiveness and side effects to existing drugs, but with a more ambiguous evidence base around adverse effects. Despite this, new treatments drive increased health care spending, suggesting a preference for 'newness' in this setting. We explore (1) whether preferences for treatments labeled 'new' exist and (2) persist once the ambiguity in the evidence base reflecting newness is described. We use a Canadian general population sample (n = 2837) characterized by their innovativeness in adopting new products in normal markets. We found that innovators/early adopters (n = 173) had significant preferences for 'newer' treatments (B = 0.162, p = 0.038) irrespective of comparable benefits and side effects and all respondents had significant preferences for less ambiguity in benefit/side effect estimates. Notably, when 'newness' was combined with ambiguity, no significant preferences for new treatments were observed regardless of respondent innovativeness. We conclude that preferences for new products exist for some people in health care markets but disappear when the implication of ambiguity in the evidence base for new treatments is communicated. Physicians should avoid describing treatments as 'new' or be mindful to qualify the implications of 'new' treatments in terms of evidence ambiguity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. PRF Ambiguity Detrmination for Radarsat ScanSAR System

    Science.gov (United States)

    Jin, Michael Y.

    1998-01-01

    PRF ambiguity is a potential problem for a spaceborne SAR operated at high frequencies. For a strip mode SAR, there were several approaches to solve this problem. This paper, however, addresses PRF ambiguity determination algorithms suitable for a burst mode SAR system such as the Radarsat ScanSAR. The candidate algorithms include the wavelength diversity algorithm, range look cross correlation algorithm, and multi-PRF algorithm.

  4. Confronting Ambiguity in Science

    Science.gov (United States)

    Emery, Katherine; Harlow, Danielle; Whitmer, Ali; Gaines, Steven

    2015-01-01

    People are regularly confronted with environmental and science-related issues presented to them in newspapers, on television, or even in their own doctor's office. Often the information they use to inform their decisions on matters of science may be ambiguous and contradictory. This article presents an activity that investigates how students deal…

  5. ‘Everything revolves around gymnastics’: athletes and parents make sense of elite youth sport.

    NARCIS (Netherlands)

    Smits, Froukje; Jacobs, F.M.; Knoppers, A.E.

    2017-01-01

    The continuation of emotional abuse as a normalized practice in elite youth sport has received scholarly attention, often with the use of a Foucauldian framework. The use of sense-making, a theoretical framework that focuses on how meaning is created in ambiguous situations, may give additional

  6. ‘Everything revolves around gymnastics’: athletes and parents make sense of elite youth sport

    NARCIS (Netherlands)

    Froukje Smits; Frank Jacobs; Annelies Knoppers

    2017-01-01

    The continuation of emotional abuse as a normalized practice in elite youth sport has received scholarly attention, often with the use of a Foucauldian framework. The use of sense-making, a theoretical framework that focuses on how meaning is created in ambiguous situations, may give additional

  7. Process ambiguities in Sino-Danish Business Negotiations

    DEFF Research Database (Denmark)

    Kumar, Rajesh; Worm, Verner

    2004-01-01

    . These ambiguities stem from differences in negotiation scripts across Danish and Chinese cultures. The essential argument being advanced here is that it is the effective and/or the ineffective management of process ambiguities that shapes the evolution of the negotiating dynamic between the Danish and the Chinese...... businesspeople. An inductive model of sino-Danish negotiations is developed that is based on 24 interviews conducted with Danish expatriate managers in China and 4 interviews with Chinese working in Danish companies. Implications for research and practice are discussed...

  8. The classification of ambiguity in polarimetric reconstruction of coronal mass ejection

    International Nuclear Information System (INIS)

    Dai, Xinghua; Wang, Huaning; Huang, Xin; Du, Zhanle; He, Han

    2014-01-01

    The Thomson scattering theory indicates that there exist explicit and implicit ambiguities in polarimetric analyses of coronal mass ejection (CME) observations. We suggest a classification for these ambiguities in CME reconstruction. Three samples, including double explicit, mixed, and double implicit ambiguity, are shown with the polarimetric analyses of STEREO CME observations. These samples demonstrate that this classification is helpful for improving polarimetric reconstruction.

  9. U.S./Arab Reflections on Our Tolerance for Ambiguity

    Science.gov (United States)

    Bright, Larry K.; Mahdi, Ghada S.

    2012-01-01

    As the authors, a Midwestern American educational administration professor and a Middle Eastern Iraqi doctoral candidate, have continued to interact over the past 3 years, both have come to appreciate the importance of increasing their tolerance for ambiguity--ambiguities in examining cultural, linguistic, and religious customs and complexities in…

  10. Effective potential for bilocal composite fields and its ambiguity

    International Nuclear Information System (INIS)

    Muta, T.

    1988-01-01

    It is discussed that an ambiguity exists in the definition of the effective potential for bilocal composite fields which is an indispensable tool to discuss dynamical symmetry breaking. The ambiguity gives warning to arguments on the stability of ground states based on the curvature of the effective potential

  11. Examining English-German Translation Ambiguity Using Primed Translation Recognition

    Science.gov (United States)

    Eddington, Chelsea M.; Tokowicz, Natasha

    2013-01-01

    Many words have more than one translation across languages. Such "translation-ambiguous" words are translated more slowly and less accurately than their unambiguous counterparts. We examine the extent to which word context and translation dominance influence the processing of translation-ambiguous words. We further examine how these factors…

  12. Quantification Scope Ambiguity Resolution: Evidence from Persian and English

    Science.gov (United States)

    Asadollahfam, Hassan; Lotfi, Ahmad Reza

    2010-01-01

    This study investigates the interpretation of scopally ambiguous sentences containing noun phrases with double quantified constituents from a processing perspective. The questions this study tried to answer were: whether or not the preferred interpretation for doubly quantified ambiguous sentences in English was influenced by English learners' L1…

  13. Azimuth Ambiguities Removal in Littoral Zones Based on Multi-Temporal SAR Images

    Directory of Open Access Journals (Sweden)

    Xiangguang Leng

    2017-08-01

    Full Text Available Synthetic aperture radar (SAR is one of the most important techniques for ocean monitoring. Azimuth ambiguities are a real problem in SAR images today, which can cause performance degradation in SAR ocean applications. In particular, littoral zones can be strongly affected by land-based sources, whereas they are usually regions of interest (ROI. Given the presence of complexity and diversity in littoral zones, azimuth ambiguities removal is a tough problem. As SAR sensors can have a repeat cycle, multi-temporal SAR images provide new insight into this problem. A method for azimuth ambiguities removal in littoral zones based on multi-temporal SAR images is proposed in this paper. The proposed processing chain includes co-registration, local correlation, binarization, masking, and restoration steps. It is designed to remove azimuth ambiguities caused by fixed land-based sources. The idea underlying the proposed method is that sea surface is dynamic, whereas azimuth ambiguities caused by land-based sources are constant. Thus, the temporal consistence of azimuth ambiguities is higher than sea clutter. It opens up the possibilities to use multi-temporal SAR data to remove azimuth ambiguities. The design of the method and the experimental procedure are based on images from the Sentinel data hub of Europe Space Agency (ESA. Both Interferometric Wide Swath (IW and Stripmap (SM mode images are taken into account to validate the proposed method. This paper also presents two RGB composition methods for better azimuth ambiguities visualization. Experimental results show that the proposed method can remove azimuth ambiguities in littoral zones effectively.

  14. Phase ambiguity resolution for offset QPSK modulation systems

    Science.gov (United States)

    Nguyen, Tien M. (Inventor)

    1991-01-01

    A demodulator for Offset Quaternary Phase Shift Keyed (OQPSK) signals modulated with two words resolves eight possible combinations of phase ambiguity which may produce data error by first processing received I(sub R) and Q(sub R) data in an integrated carrier loop/symbol synchronizer using a digital Costas loop with matched filters for correcting four of eight possible phase lock errors, and then the remaining four using a phase ambiguity resolver which detects the words to not only reverse the received I(sub R) and Q(sub R) data channels, but to also invert (complement) the I(sub R) and/or Q(sub R) data, or to at least complement the I(sub R) and Q(sub R) data for systems using nontransparent codes that do not have rotation direction ambiguity.

  15. Semantic Ambiguity: Do Multiple Meanings Inhibit or Facilitate Word Recognition?

    Science.gov (United States)

    Haro, Juan; Ferré, Pilar

    2018-06-01

    It is not clear whether multiple unrelated meanings inhibit or facilitate word recognition. Some studies have found a disadvantage for words having multiple meanings with respect to unambiguous words in lexical decision tasks (LDT), whereas several others have shown a facilitation for such words. In the present study, we argue that these inconsistent findings may be due to the approach employed to select ambiguous words across studies. To address this issue, we conducted three LDT experiments in which we varied the measure used to classify ambiguous and unambiguous words. The results suggest that multiple unrelated meanings facilitate word recognition. In addition, we observed that the approach employed to select ambiguous words may affect the pattern of experimental results. This evidence has relevant implications for theoretical accounts of ambiguous words processing and representation.

  16. The Benefit of Ambiguity in Understanding Goals in Requirements Modelling

    DEFF Research Database (Denmark)

    Paay, Jeni; Pedell, Sonja; Sterling, Leon

    2011-01-01

    This paper examines the benefit of ambiguity in describing goals in requirements modelling for the design of socio-technical systems using concepts from Agent-Oriented Software Engineering (AOSE) and ethnographic and cultural probe methods from Human Computer Interaction (HCI). The authors’ aim...... ambiguity in the process of elicitation and analysis through the use of empirically informed quality goals attached to functional goals. The authors demonstrate the benefit of articulating a quality goal without turning it into a functional goal. Their study shows that quality goals kept at a high level...... of abstraction, ambiguous and open for conversations through the modelling process add richness to goal models, and communicate quality attributes of the interaction being modelled to the design phase, where this ambiguity is regarded as a resource for design....

  17. Extent of the Immirzi ambiguity in quantum general relativity

    International Nuclear Information System (INIS)

    Marugan, Guillermo A Mena

    2002-01-01

    The Ashtekar-Barbero formulation of general relativity admits a one-parameter family of canonical transformations that preserves the expressions of the Gauss and diffeomorphism constraints. The loop quantization of the connection formalism based on each of these canonical sets leads to different predictions. This phenomenon is called the Immirzi ambiguity. It has been recently argued that this ambiguity could be generalized to the extent of a spatially dependent function instead of a parameter. This would ruin the predictability of loop quantum gravity. We prove that such expectations are not realized, so that the Immirzi ambiguity introduces exclusively a freedom in the choice of a real number. (letter to the editor)

  18. Children's Understanding of Ambiguous Idioms and Conversational Perspective-Taking

    Science.gov (United States)

    Le Sourn-Bissaoui, Sandrine; Caillies, Stephanie; Bernard, Stephane; Deleau, Michel; Brule, Lauriane

    2012-01-01

    The aim of this study was to test the hypothesis that conversational perspective-taking is a determinant of unfamiliar ambiguous idiom comprehension. We investigated two types of ambiguous idiom, decomposable and nondecomposable expressions, which differ in the degree to which the literal meanings of the individual words contribute to the overall…

  19. Semantic ambiguity processing in sentence context: Evidence from event-related fMRI

    NARCIS (Netherlands)

    Zempleni, Monika-Zita; Renken, Remco; Hoeks, John C. J.; Hoogduin, Johannes M.; Stowe, Laurie A.

    2007-01-01

    Lexical semantic ambiguity is the phenomenon when a word has multiple meanings (e.g. 'bank'). The aim of this event-related functional MRI study was to identify those brain areas, which are involved in contextually driven ambiguity resolution. Ambiguous words were selected which have a most

  20. High energy collisions and the proton structure: an ambiguity

    International Nuclear Information System (INIS)

    Franca, H.M.

    1980-01-01

    It is pointed out an ambiguity in the determination of the sign of the imaginary part of the proton-proton elastic-scattering amplitude for ]t]>]t min . Some implications of such and ambiguity concerning the proton structure are discussed and finally, an experimental analysis which could solve it is suggested. (L.C.) [pt

  1. Instructor Strategic Ambiguity: Delineation of the Construct and Development of a Measure

    Science.gov (United States)

    Klyukovski, Andrei A.; Medlock-Klyukovski, Amanda L.

    2016-01-01

    This article presents research to delineate the construct of instructor strategic ambiguity (ISA) and develop a measure. The first study analyzed instructor uses of ambiguity, identified 18 strategies, and classified them into four categories. The second study developed an Instructor Strategic Ambiguity Measure (ISAM) for the college classroom.…

  2. Making sense of war : Using the interpretation comparison model to understand the Iraq conflict

    NARCIS (Netherlands)

    Stapel, Diederik A.; Marx, David M.

    2007-01-01

    The current research addressed the issue of how people use the past to compare and interpret the present. Using the logic of the Interpretation Comparison Model (ICM) we examined two factors (distinctness of past events and ambiguity of target event) that may influence how people make sense of a

  3. Three-dimensional sensing methodology combining stereo vision and phase-measuring profilometry based on dynamic programming

    Science.gov (United States)

    Lee, Hyunki; Kim, Min Young; Moon, Jeon Il

    2017-12-01

    Phase measuring profilometry and moiré methodology have been widely applied to the three-dimensional shape measurement of target objects, because of their high measuring speed and accuracy. However, these methods suffer from inherent limitations called a correspondence problem, or 2π-ambiguity problem. Although a kind of sensing method to combine well-known stereo vision and phase measuring profilometry (PMP) technique simultaneously has been developed to overcome this problem, it still requires definite improvement for sensing speed and measurement accuracy. We propose a dynamic programming-based stereo PMP method to acquire more reliable depth information and in a relatively small time period. The proposed method efficiently fuses information from two stereo sensors in terms of phase and intensity simultaneously based on a newly defined cost function of dynamic programming. In addition, the important parameters are analyzed at the view point of the 2π-ambiguity problem and measurement accuracy. To analyze the influence of important hardware and software parameters related to the measurement performance and to verify its efficiency, accuracy, and sensing speed, a series of experimental tests were performed with various objects and sensor configurations.

  4. Human Perception of Ambiguous Inertial Motion Cues

    Science.gov (United States)

    Zhang, Guan-Lu

    2010-01-01

    Human daily activities on Earth involve motions that elicit both tilt and translation components of the head (i.e. gazing and locomotion). With otolith cues alone, tilt and translation can be ambiguous since both motions can potentially displace the otolithic membrane by the same magnitude and direction. Transitions between gravity environments (i.e. Earth, microgravity and lunar) have demonstrated to alter the functions of the vestibular system and exacerbate the ambiguity between tilt and translational motion cues. Symptoms of motion sickness and spatial disorientation can impair human performances during critical mission phases. Specifically, Space Shuttle landing records show that particular cases of tilt-translation illusions have impaired the performance of seasoned commanders. This sensorimotor condition is one of many operational risks that may have dire implications on future human space exploration missions. The neural strategy with which the human central nervous system distinguishes ambiguous inertial motion cues remains the subject of intense research. A prevailing theory in the neuroscience field proposes that the human brain is able to formulate a neural internal model of ambiguous motion cues such that tilt and translation components can be perceptually decomposed in order to elicit the appropriate bodily response. The present work uses this theory, known as the GIF resolution hypothesis, as the framework for experimental hypothesis. Specifically, two novel motion paradigms are employed to validate the neural capacity of ambiguous inertial motion decomposition in ground-based human subjects. The experimental setup involves the Tilt-Translation Sled at Neuroscience Laboratory of NASA JSC. This two degree-of-freedom motion system is able to tilt subjects in the pitch plane and translate the subject along the fore-aft axis. Perception data will be gathered through subject verbal reports. Preliminary analysis of perceptual data does not indicate that

  5. Bank risk, bailouts and ambiguity

    NARCIS (Netherlands)

    Nijskens, R.G.M.

    2012-01-01

    The theoretical analysis in the second part investigates the effect of liquidity assistance and bailouts on bank risk taking and liquidity choice. Furthermore, it explores the possibilities for central banks to create ambiguity about liquidity assistance, thereby influencing bank choices. The

  6. The ambiguity of simplicity in quantum and classical simulation

    International Nuclear Information System (INIS)

    Aghamohammadi, Cina; Mahoney, John R.; Crutchfield, James P.

    2017-01-01

    Highlights: • Simplicity depends on whether a system is represented classically or quantally. • We demonstrate that simplicity is unavoidably ambiguous. • Relative simplicity changes order moving between classical and quantum descriptions. • Ambiguity of simplicity bears directly on model selection. - Abstract: A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the “elegance” of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

  7. Ambiguity resolution for satellite Doppler positioning systems

    Science.gov (United States)

    Argentiero, P.; Marini, J.

    1979-01-01

    The implementation of satellite-based Doppler positioning systems frequently requires the recovery of transmitter position from a single pass of Doppler data. The least-squares approach to the problem yields conjugate solutions on either side of the satellite subtrack. It is important to develop a procedure for choosing the proper solution which is correct in a high percentage of cases. A test for ambiguity resolution which is the most powerful in the sense that it maximizes the probability of a correct decision is derived. When systematic error sources are properly included in the least-squares reduction process to yield an optimal solution the test reduces to choosing the solution which provides the smaller valuation of the least-squares loss function. When systematic error sources are ignored in the least-squares reduction, the most powerful test is a quadratic form comparison with the weighting matrix of the quadratic form obtained by computing the pseudoinverse of a reduced-rank square matrix. A formula for computing the power of the most powerful test is provided. Numerical examples are included in which the power of the test is computed for situations that are relevant to the design of a satellite-aided search and rescue system.

  8. Chains of phase-shift ambiguities in elastic spin-0-spin-1/2 scattering

    International Nuclear Information System (INIS)

    Berends, F.A.; Reisen, J.C.J.M. van

    1977-01-01

    It is shown, that a previously constructed phase-shift ambiguity for an arbitrary number, 2L + 1, of partial waves can be connected to L - 1 other ambiguities. The two sets of phase shifts defined by the chain of ambiguities become equal (modulo π) at the endpoints of the chain, but in general not at the endpoints of the ambiguities. Also other examples of such chains are given. (Auth.)

  9. Origin of the Gribov ambiguity

    International Nuclear Information System (INIS)

    Takahashi, Y.; Kobayashi, M.

    1978-01-01

    It is pointed out that the Gribov ambiguity for the non-abelian transverse gauge field has the same origin as the Johnson-Sudarshan problem for the spin-3/2 field as well as the propagation problem discovered by Velo and Zwanziger. (Auth.)

  10. The known unknowns: neural representation of second-order uncertainty, and ambiguity

    Science.gov (United States)

    Bach, Dominik R.; Hulme, Oliver; Penny, William D.; Dolan, Raymond J.

    2011-01-01

    Predictions provided by action-outcome probabilities entail a degree of (first-order) uncertainty. However, these probabilities themselves can be imprecise and embody second-order uncertainty. Tracking second-order uncertainty is important for optimal decision making and reinforcement learning. Previous functional magnetic resonance imaging investigations of second-order uncertainty in humans have drawn on an economic concept of ambiguity, where action-outcome associations in a gamble are either known (unambiguous) or completely unknown (ambiguous). Here, we relaxed the constraints associated with a purely categorical concept of ambiguity and varied the second-order uncertainty of gambles continuously, quantified as entropy over second-order probabilities. We show that second-order uncertainty influences decisions in a pessimistic way by biasing second-order probabilities, and that second-order uncertainty is negatively correlated with posterior cingulate cortex activity. The category of ambiguous (compared to non-ambiguous) gambles also biased choice in a similar direction, but was associated with distinct activation of a posterior parietal cortical area; an activation that we show reflects a different computational mechanism. Our findings indicate that behavioural and neural responses to second-order uncertainty are distinct from those associated with ambiguity and may call for a reappraisal of previous data. PMID:21451019

  11. Top-Down Influence in Young Children's Linguistic Ambiguity Resolution

    Science.gov (United States)

    Rabagliati, Hugh; Pylkkanen, Liina; Marcus, Gary F.

    2013-01-01

    Language is rife with ambiguity. Do children and adults meet this challenge in similar ways? Recent work suggests that while adults resolve syntactic ambiguities by integrating a variety of cues, children are less sensitive to top-down evidence. We test whether this top-down insensitivity is specific to syntax or a general feature of children's…

  12. Degenerate gauge conditions, generalized Gribov's ambiguity and BRST symmetry

    International Nuclear Information System (INIS)

    Fabbrichesi, M.E.

    1987-01-01

    The BFS-BRST approach to gauge theories is considered. It is argued that the BRST-invariant boundary conditions ordinarily used do not maintain the necessary degeneracy in the gauge fixing. As a by-product of this discussion, the existence of a generalized Gribov-like ambiguity is suggested. This ambiguity is however shown to be just a particular BRST transformation

  13. Pericentric Inversion of Chromosome 9 in an Infant With Ambiguous Genitalia.

    Science.gov (United States)

    Sotoudeh, Arya; Rostami, Parastoo; Nakhaeimoghadam, Maryam; Mohsenipour, Reihaneh; Rezaei, Nima

    2017-10-01

    Pericentric inversion of Chromosome 9 is one of the most common chromosomal abnormalities, which could be associated with various manifestations in some cases. Herein, a patient is presented with ambiguous genitalia that karyotyping revealed pericentric inversion of Chromosome 9 (p12,q13). Pericentric inversion of Chromosome 9 could be considered in the list of differential diagnosis of those with ambiguous genitalia, while chromosomal karyotype and culture could be recommended in children with ambiguous genitalia.

  14. Comparing the ambiguity reduction abilities of probabilistic context-free grammars

    NARCIS (Netherlands)

    Infante-Lopez, G.G.; de Rijke, M.

    2004-01-01

    We present a measure for evaluating Probabilistic Context Free Grammars (PCFG) based on their ambiguity resolution capabilities.Probabilities in a PCFG can be seen as a filtering mechanism: For an ambiguous sentence, the trees bearing maximum probability aresingle out, while all others are

  15. A study of potential sources of linguistic ambiguity in written work instructions.

    Energy Technology Data Exchange (ETDEWEB)

    Matzen, Laura E.

    2009-11-01

    This report describes the results of a small experimental study that investigated potential sources of ambiguity in written work instructions (WIs). The English language can be highly ambiguous because words with different meanings can share the same spelling. Previous studies in the nuclear weapons complex have shown that ambiguous WIs can lead to human error, which is a major cause for concern. To study possible sources of ambiguity in WIs, we determined which of the recommended action verbs in the DOE and BWXT writer's manuals have numerous meanings to their intended audience, making them potentially ambiguous. We used cognitive psychology techniques to conduct a survey in which technicians who use WIs in their jobs indicated the first meaning that came to mind for each of the words. Although the findings of this study are limited by the small number of respondents, we identified words that had many different meanings even within this limited sample. WI writers should pay particular attention to these words and to their most frequent meanings so that they can avoid ambiguity in their writing.

  16. Optimal observables and phase-space ambiguities

    International Nuclear Information System (INIS)

    Nachtmann, O.; Nagel, F.

    2005-01-01

    Optimal observables are known to lead to minimal statistical errors on parameters for a given normalised event distribution of a physics reaction. Thereby all statistical correlations are taken into account. Therefore, on the one hand they are a useful tool to extract values on a set of parameters from measured data. On the other hand one can calculate the minimal constraints on these parameters achievable by any data-analysis method for the specific reaction. In case the final states can be reconstructed without ambiguities optimal observables have a particularly simple form. We give explicit formulae for the optimal observables for generic reactions in case of ambiguities in the reconstruction of the final state and for general parameterisation of the final-state phase space. (orig.)

  17. On ambiguities in the exponentiation of large QCD perturbative corrections

    International Nuclear Information System (INIS)

    Chyla, Jiri

    1986-01-01

    Ambiguities and some practical questions connected with the exponentiation of higher-order QCD perturbative corrections are discussed for the case of deep inelastic lepton-hadron scattering in the non-singlet channel. The importance of still higher-order calculations for resolving these ambiguities is stressed. (author)

  18. Sense and Respond Logistics: Integrating Prediction, Responsiveness, and Control Capabilities

    Science.gov (United States)

    2006-01-01

    location. In the current environment, increased ambiguity has diminished this advantage and increased the need for a sense and respond combat...readily be applied to system dynamics prob- lems in business and organization processes. ABMs bring the “natu- ralness” advantage (which allows more...negotiation) as part of eCommerce applications being achieved by 2007. In the general opinion of AgentLink’s respondents, as well as our technology

  19. Ambiguities of the natural gauge in Yang-Mills theories

    International Nuclear Information System (INIS)

    Lazarides, G.

    1978-01-01

    We study the ambiguities of the natural gauge condition for the Euclidean SU(2) Yang-Mills theory in four dimensions. Then, we show that, in the stationary-phase approximation, these ambiguities do not affect the contribution of the sector with Pontryagin index q = 1 to the correlation functions of gauge-invariant operators. They affect only the higher-order corrections to this contribution

  20. Clock ambiguity and the emergence of physical laws

    International Nuclear Information System (INIS)

    Albrecht, Andreas; Iglesias, Alberto

    2008-01-01

    The process of identifying a time variable in time-reparameterization invariant theories results in great ambiguities about the actual laws of physics described by a given theory. A theory set up to describe one set of physical laws can equally well be interpreted as describing any other laws of physics by making a different choice of time variable or clock. In this article we demonstrate how this 'clock ambiguity' arises and then discuss how one might still hope to extract specific predictions about the laws of physics even when the clock ambiguity is present. We argue that a requirement of quasiseparability should play a critical role in such an analysis. As a step in this direction, we compare the Hamiltonian of a local quantum field theory with a completely random Hamiltonian. We find that any random Hamiltonian (constructed in a sufficiently large space) can yield a 'good enough' approximation to a local field theory. Based on this result we argue that theories that suffer from the clock ambiguity may in the end provide a viable fundamental framework for physics in which locality can be seen as a strongly favored (or predicted) emergent behavior. We also speculate on how other key aspects of known physics such as gauge symmetries and Poincare invariance might be predicted to emerge in this framework.

  1. DIFFERENCES OF THE ROLE AMBIGUITY IN OFFENSE RESPONSIBILITIES OF TEAM SPORTS

    Directory of Open Access Journals (Sweden)

    Karamousalidis, G.

    2009-10-01

    Full Text Available The purpose of this research was to investigate the differences of the role ambiguity in offense responsibilitiesfor athletes of team sports. As sample were used 421 athletes of basketball (n=125, handball (n=106, volleyball(n=78 and soccer (n=112. We used the role ambiguity questionnaire (Role Ambiguity Scale, Beauchamp et al.,2002 and referred to the athletes’ responsibilities in offense.The correlations of items were high and ranged from .57 to .75, p <.01 whereas from the one way analysis (oneway, Anova appeared some statistically serious differences in one factor of role ambiguity (ambiguity inrelation to the scope of responsibilities in offense, F (3,415 = 4,416, p <.005. The volleyball and the handballathletes had more well defined roles regardless the scope of their responsibilities in offense, in relation to thoseof soccer. On the whole we come to the conclusion that among team sports there are not any differences in roleambiguity in offense responsibilities, except in one factor. More researches are necessary in connection to othervariables.

  2. Ambiguity Tolerance and Perceptual Learning Styles of Chinese EFL Learners

    Science.gov (United States)

    Li, Haishan; He, Qingshun

    2016-01-01

    Ambiguity tolerance and perceptual learning styles are the two influential elements showing individual differences in EFL learning. This research is intended to explore the relationship between Chinese EFL learners' ambiguity tolerance and their preferred perceptual learning styles. The findings include (1) the learners are sensitive to English…

  3. Tracking Down the Origins of Ambiguity in Context-Free Grammars

    NARCIS (Netherlands)

    H.J.S. Basten (Bas)

    2010-01-01

    htmlabstractContext-free grammars are widely used but still hindered by ambiguity. This stresses the need for detailed detection methods that point out the sources of ambiguity in a grammar. In this paper we show how the approximative Noncanonical Unambiguity Test by Schmitz can be extended to

  4. Ambiguity: A new way of thinking about responses to climate change.

    Science.gov (United States)

    Fleming, A; Howden, S M

    2016-11-15

    Diversity, interdisciplinarity and transdisciplinarity are now recognized as vital to tackling wicked problems such as those presented by a changing climate (Nature editorial 2015, Ledford 2015; Dick et al., 2016). Including diverse disciplines in science projects enables a range of different views which often facilitate the creation of innovative solutions. Supporting multiple views and options requires a different way of working beyond traditional reductionist approaches to science, communication and decision-making. To embrace diversity in scientific project teams in order to tackle complex, integrated and urgent issues but to expect singular and linear pathways forward is paradoxical. Much has been written about the need for the scientific community to embrace uncertainty (e.g. Popper, Lempert & Bankes 2005; Lempert et al., 2004; Nelson, Howden & Hayman 2013; Bammer & Smithson 2008). We argue that this in itself will not suffice, and that there is also a need to embrace ambiguity in certain situations. Thus, in this article we explore: (1) what ambiguity is, including the benefits it can offer to climate adaptation in particular, using existing approaches to ambiguity in the arts and humanities as examples (2), we discuss practical meanings of ambiguity in relation to climate change, (3) we propose possible next steps for bringing ambiguity into interdisciplinary practice, and (4) we identify some challenges and necessary preconditions to successfully and appropriately embracing ambiguity. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. The ambiguity of simplicity in quantum and classical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Aghamohammadi, Cina, E-mail: caghamohammadi@ucdavis.edu; Mahoney, John R., E-mail: jrmahoney@ucdavis.edu; Crutchfield, James P., E-mail: chaos@ucdavis.edu

    2017-04-11

    Highlights: • Simplicity depends on whether a system is represented classically or quantally. • We demonstrate that simplicity is unavoidably ambiguous. • Relative simplicity changes order moving between classical and quantum descriptions. • Ambiguity of simplicity bears directly on model selection. - Abstract: A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the “elegance” of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

  6. The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language.

    Science.gov (United States)

    Lu, Yao; Wu, Junjie; Dunlap, Susan; Chen, Baoguo

    2017-01-01

    Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2) learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese-English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning) and half were ambiguous (had two semantically unrelated meanings learned in sequence). Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

  7. The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language

    Directory of Open Access Journals (Sweden)

    Baoguo Chen

    2017-04-01

    Full Text Available Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2 learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese–English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning and half were ambiguous (had two semantically unrelated meanings learned in sequence. Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

  8. Phase-ambiguity resolution for QPSK modulation systems. Part 1: A review

    Science.gov (United States)

    Nguyen, Tien Manh

    1989-01-01

    Part 1 reviews the current phase-ambiguity resolution techniques for QPSK coherent modulation systems. Here, those known and published methods of resolving phase ambiguity for QPSK with and without Forward-Error-Correcting (FEC) are discussed. The necessary background is provided for a complete understanding of the second part where a new technique will be discussed. An appropriate technique to the Consultative Committee for Space Data Systems (CCSDS) is recommended for consideration in future standards on phase-ambiguity resolution for QPSK coherent modulation systems.

  9. Ambiguous taxa: Effects on the characterization and interpretation of invertebrate assemblages

    Science.gov (United States)

    Cuffney, T.F.; Bilger, Michael D.; Haigler, A.M.

    2007-01-01

    Damaged and immature specimens often result in macroinvertebrate data that contain ambiguous parent-child pairs (i.e., abundances associated with multiple related levels of the taxonomic hierarchy such as Baetis pluto and the associated ambiguous parent Baetis sp.). The choice of method used to resolve ambiguous parent-child pairs may have a very large effect on the characterization of invertebrate assemblages and the interpretation of responses to environmental change because very large proportions of taxa richness (73-78%) and abundance (79-91%) can be associated with ambiguous parents. To address this issue, we examined 16 variations of 4 basic methods for resolving ambiguous taxa: RPKC (remove parent, keep child), MCWP (merge child with parent), RPMC (remove parent or merge child with parent depending on their abundances), and DPAC (distribute parents among children). The choice of method strongly affected assemblage structure, assemblage characteristics (e.g., metrics), and the ability to detect responses along environmental (urbanization) gradients. All methods except MCWP produced acceptable results when used consistently within a study. However, the assemblage characteristics (e.g., values of assemblage metrics) differed widely depending on the method used, and data should not be combined unless the methods used to resolve ambiguous taxa are well documented and are known to be comparable. The suitability of the methods was evaluated and compared on the basis of 13 criteria that considered conservation of taxa richness and abundance, consistency among samples, methods, and studies, and effects on the interpretation of the data. Methods RPMC and DPAC had the highest suitability scores regardless of whether ambiguous taxa were resolved for each sample separately or for a group of samples. Method MCWP gave consistently poor results. Methods MCWP and DPAC approximate the use of family-level identifications and operational taxonomic units (OTU), respectively. Our

  10. Estimating Ambiguity Preferences and Perceptions in Multiple Prior Models: Evidence from the Field

    NARCIS (Netherlands)

    S.G. Dimmock (Stephen); R.R.P. Kouwenberg (Roy); O.S. Mitchell (Olivia); K. Peijnenburg (Kim)

    2015-01-01

    markdownabstractWe develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of

  11. Evaluation of ambiguous genitalia with MR imaging

    International Nuclear Information System (INIS)

    Secaf, E.; Nuruddin, R.; Hricak, H.; Conte, F.A.

    1989-01-01

    To assess the potential of MR imaging in the evaluation of patients with ambiguous genitalia. Twenty-three consecutive patients with ambiguous genitalia at birth or phenotypic anomalies at puberty were included in this study. MR imaging was performed on a 1.5-T unit using T1- (600/30) and T2- (2,500/70) weighted sequences. In patients aged 5 years or less, 3-mm contiguous sagittal and transaxial sections were obtained. The same imaging planes at 5-mm intervals were obtained in older patients. MR findings were compared to those of surgery (n = 14) or biochemical assays (n = 9). Diagnoses included true hermaphroditism (n = 2), pseudohermaphroditism (n = 6), Turner syndrome (n = 2), testicular feminization (n = 2), adrenogenital syndrome (n = 3), vaginal agenesis (n = 3), cloacal abnormality (n = 2), microphallus (n = 2), and double phallus (n = 1. MR imaging correctly identified the presence or absence of the vagina (n = 10) and uterus (n = 9), thus helping in the diagnosis and management of patients with ambiguous genitalia. Demonstration of development of corpora cavernosa, corpora spongiosa, undescended testis, or partial vaginal agenesis assisted in the surgical approach

  12. New Times, New Heroes : Ambiguity, Socio-Political Issues and Post Modernism in Frank Miller's Graphic Novel The Dark Knight Returns

    OpenAIRE

    Axelsson, Jan

    2013-01-01

    Frank Miller’s The Dark Knight Returns is one of the first graphic novels to redraw the map for this kind of literature but perhaps first and foremost for the characteristics of superheroes and villains. It is a story which we have read before in the sense that Batman, the eternal crime fighter, chases his arch enemies Two Face and the Joker, but it is also a new story in which we meet an ambiguous and complex superhero. Batman has become an old man tormented by his past, in which his side ki...

  13. Lexical ambiguity resolution during sentence processing in Parkinson's disease: An event-related potential study.

    Directory of Open Access Journals (Sweden)

    Anthony J Angwin

    Full Text Available Event-related potentials (ERPs were recorded to investigate lexical ambiguity resolution during sentence processing in 16 people with Parkinson's disease (PD and 16 healthy controls. Sentences were presented word-by-word on computer screen, and participants were required to decide if a subsequent target word was related to the meaning of the sentence. The task consisted of related, unrelated and ambiguous trials. For the ambiguous trials, the sentence ended with an ambiguous word and the target was related to one of the meanings of that word, but not the one captured by the sentence context (e.g., 'He dug with the spade', Target 'ACE'. Both groups demonstrated slower reaction times and lower accuracy for the ambiguous condition relative to the unrelated condition, however accuracy was impacted by the ambiguous condition to a larger extent in the PD group. These results suggested that PD patients experience increased difficulties with contextual ambiguity resolution. The ERP results did not reflect increased ambiguity resolution difficulties in PD, as a similar N400 effect was evident for the unrelated and ambiguous condition in both groups. However, the magnitude of the N400 for these conditions was correlated with a measure of inhibition in the PD group, but not the control group. The ERP results suggest that semantic processing may be more compromised in PD patients with increased response inhibition deficits.

  14. Theory-Based Evaluation Meets Ambiguity: The Role of Janus Variables

    Science.gov (United States)

    Dahler-Larsen, Peter

    2018-01-01

    As theory-based evaluation (TBE) engages in situations where multiple stakeholders help develop complex program theory about dynamic phenomena in politically contested settings, it becomes difficult to develop and use program theory without ambiguity. The purpose of this article is to explore ambiguity as a fruitful perspective that helps TBE face…

  15. Identification and Definition of Lexically Ambiguous Words in Statistics by Tutors and Students

    Science.gov (United States)

    Richardson, Alice M.; Dunn, Peter K.; Hutchins, Rene

    2013-01-01

    Lexical ambiguity arises when a word from everyday English is used differently in a particular discipline, such as statistics. This paper reports on a project that begins by identifying tutors' perceptions of words that are potentially lexically ambiguous to students, in two different ways. Students' definitions of nine lexically ambiguous words…

  16. Spectral Ambiguity of Allan Variance

    Science.gov (United States)

    Greenhall, C. A.

    1996-01-01

    We study the extent to which knowledge of Allan variance and other finite-difference variances determines the spectrum of a random process. The variance of first differences is known to determine the spectrum. We show that, in general, the Allan variance does not. A complete description of the ambiguity is given.

  17. Ambiguity in Speaking Chemistry and Other STEM Content: Educational Implications

    Science.gov (United States)

    Isaacson, Mick D.; Michaels, Michelle

    2015-01-01

    Ambiguity in speech is a possible barrier to the acquisition of knowledge for students who have print disabilities (such as blindness, visual impairments, and some specific learning disabilities) and rely on auditory input for learning. Chemistry appears to have considerable potential for being spoken ambiguously and may be a barrier to accessing…

  18. Electrodermal responses during appetitive conditioning are sensitive to contingency instruction ambiguity.

    Science.gov (United States)

    van den Akker, Karolien; Nederkoorn, Chantal; Jansen, Anita

    2017-08-01

    Studies on human appetitive conditioning using food rewards can benefit from including psychophysiological outcome measures. The present study tested whether the skin conductance response can function as a measure of differential responding in an appetitive conditioning paradigm including an acquisition and extinction phase, and examined which time window during a trial is most sensitive to conditioning effects. As a secondary aim, the effects of ambiguous vs. non-ambiguous contingency instructions on conditioned responses (skin conductance responses, US expectancies, chocolate desires, and CS evaluations) were assessed. Results indicated differential skin conductance responses in an anticipatory time window and during unexpected omission of the US in early extinction. Interestingly however, anticipatory responses were only found for participants who received ambiguous contingency instructions - possibly indicating a call for additional processing resources in response to the ambiguous CS+. Further, ambiguous instructions slowed the extinction of US expectancies but did not influence chocolate desires and CS evaluations. It is concluded that skin conductance can function as a sensitive measure of differential responding in appetitive conditioning, though its sensitivity might depend on the specific task context. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Logic without unique readability - a study of semantic and syntactic ambiguity

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    One of the main reasons for introducing a formal language is to remove ambiguity, the possibility of assigning several meanings to a linguistic expression. Typically, this is achieved through ensuring unique readability of formulas by using brackets (or another convention, such as Polish notation...... not hold true universally. Whereas e.g. scope ambiguities in natural languages have been studied extensively, ambiguous formal languages have not been the focus of in depth research. Here, we lift the assumption of unique readability by omitting the brackets from propositional logic, making it possible...... to formally distinguish between syntactic and semantic ambiguity. A valuation then amounts to a semantic disambiguation, and rather than a unique valuation (truth value), there is a set of valuations corresponding to ways a formula could have been constructed. We show what happens to familiar concepts...

  20. The real potential continuous ambiguity for 90 MeV Li ions

    International Nuclear Information System (INIS)

    Cook, J.; Barnwell, J.M.; Clarke, N.M.; Griffiths, R.J.

    1980-01-01

    The features of discrete and continuous ambiguities in the real phenomenological optical potential are clarified. The continuous ambiguity in the real potential for the scattering of 90 MeV 6 Li and 7 Li ions from 27 Al is investigated. For 6 Li the ambiguity is of Igo (Phys. Rev. Lett.; 1: 72 (1958) and Phys. Rev.; 115: 1665 (1959)) type but for 7 Li it is of Vrsup(n) = constant type. The implications of this are that 7 Li is less strongly absorbed than 6 Li. (author)

  1. The impact of ambiguous economic news on uncertainty and consumer confidence

    NARCIS (Netherlands)

    Svensson, H.M.; Albæk, E.; van Dalen, A.; de Vreese, C.H.

    Journalistic practice emphasizes both positive and negative aspects of news stories. Nevertheless, the effects of ambiguous news, which includes both positive and negative information, are under-investigated. This study examines how exposure to ambiguous economic news affects uncertainty and

  2. When in doubt, seize the day? Security values, prosocial values, and proactivity under ambiguity.

    Science.gov (United States)

    Grant, Adam M; Rothbard, Nancy P

    2013-09-01

    Researchers have suggested that both ambiguity and values play important roles in shaping employees' proactive behaviors, but have not theoretically or empirically integrated these factors. Drawing on theories of situational strength and values, we propose that ambiguity constitutes a weak situation that strengthens the relationship between the content of employees' values and their proactivity. A field study of 204 employees and their direct supervisors in a water treatment plant provided support for this contingency perspective. Ambiguity moderated the relationship between employees' security and prosocial values and supervisor ratings of proactivity. Under high ambiguity, security values predicted lower proactivity, whereas prosocial values predicted higher proactivity. Under low ambiguity, values were not associated with proactivity. We replicated these findings in a laboratory experiment with 232 participants in which we measured proactivity objectively as initiative taken to correct errors: Participants with strong security values were less proactive, and participants with strong prosocial values were more proactive, but only when performance expectations were ambiguous. We discuss theoretical implications for research on proactivity, values, and ambiguity and uncertainty. PsycINFO Database Record (c) 2013 APA, all rights reserved

  3. Sadder but wiser : the effects of emotional states on ambiguity attitudes

    NARCIS (Netherlands)

    Baillon, A.; Koelinger, P.; Treffers, T.

    “Many important decisions are made without precise information about the probabilities of the outcomes. In such situations, individual ambiguity attitudes influence decision making. The present study identifies emotions as a transient cause of ambiguity attitudes. We conducted two random-assignment,

  4. Psychophsyiological reactivity during uncertainty and ambiguity processing in high and low worriers.

    Science.gov (United States)

    Kirschner, Hans; Hilbert, Kevin; Hoyer, Jana; Lueken, Ulrike; Beesdo-Baum, Katja

    2016-03-01

    Intolerance of uncertainty (IU) has been linked to Generalized Anxiety Disorder (GAD), but studies experimentally manipulating uncertainty have mostly failed to find differences between GAD patients and controls, possible due to a lack of distinction between uncertainty and ambiguity. This study therefore investigated reactivity to ambiguity in addition to uncertainty in high worriers (HW) and low worriers (LW). We hypothesized an interpretation bias between the groups during ambiguity tasks, while uncertainty would facilitate threat processing of subsequent aversive stimuli. HW (N = 23) and LW (N = 23) completed a paradigm comprising the anticipation and perception of pictures with dangerous, safe, or ambiguous content. Anticipatory cues were certain (always correct information about the following picture) or uncertain (no information). Subjective ratings, reaction times and skin conductance responses (SCRs) were recorded. HW rated particularly ambiguous pictures as more aversive and showed longer reaction times to all picture conditions compared to LW. SCRs were also larger in HW compared to LW, particularly during uncertain but also safe anticipation. No group differences were observed during perception of stimuli. All participants were female. HW was used as subclinical phenotype of GAD. Intolerance of ambiguity seems to be related to individual differences in worry and possibly to the development of GAD. Threat-related interpretations differentiating HW and LW occurred particularly for ambiguous pictures but were not accompanied by increased autonomic arousal during the picture viewing. This disparity between subjective rating and arousal may be the result of worrying in response to intolerance of uncertainty, restraining physiological responses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Relation of tolerance of ambiguity to global and specific paranormal experience.

    Science.gov (United States)

    Houran, J; Williams, C

    1998-12-01

    We examined the relationship of tolerance of ambiguity to severe global factors and specific types of anomalous or paranormal experience. 107 undergraduate students completed MacDonald's 1970 AT-20 and the Anomalous Experiences Inventory of Kumar, Pekala, and Gallagher. Scores on the five subscales of the Anomalous Experiences Inventory correlated differently with tolerance of ambiguity. Global paranormal beliefs, abilities, experiences, and drug use were positively associated with tolerance of ambiguity, whereas a fear of paranormal experience showed a negative relation. The specific types of anomalous experiences that correlated with tolerance of ambiguity often involved internal or physiological experience, e.g., precognitive dreams, memories of reincarnation, visual apparitions, and vestibular alterations. We generally found no effects of age of sex. These results are consistent with the idea that some paranormal experiences are misattributions of internal experience to external ('paranormal') sources, a process analogous to mechanisms underpinning delusions and hallucinations.

  6. The ambiguity of altruism in nursing: A qualitative study.

    Science.gov (United States)

    Slettmyr, Anna; Schandl, Anna; Arman, Maria

    2017-01-01

    For a long time, altruism was the basis for caring. Today, when society is more individualized, it is of interest to explore the meaning of altruism in nursing. In all, 13 nurses from a Swedish acute care setting participated in two focus group interviews performed as Socratic dialogues. Data were analyzed using a phenomenological hermeneutical method. Ethical considerations: Ethical issues were considered throughout the process according to established ethical principles. Informed consent was obtained from all participants, confidentiality regarding the data was guaranteed and quotations anonymized. Altruism created a sense of ambivalence and ambiguity, described as a rise of sovereign expressions of life caused by "the other's" need, but also unwillingness to take unconditional responsibility for "the other." Society's expectations of altruism and nurses' perception of their work as a salaried job collide in modern healthcare. Nurses are not willing to fully respond to the ethical demand of the patients. In case of a disaster, when nurses personal safety, life and health may be at risk, there might be reasons to question whether the healthcare organization would be able to fulfill its obligations of providing healthcare to an entire population.

  7. A mixture approach to vagueness and ambiguity.

    Directory of Open Access Journals (Sweden)

    Steven Verheyen

    Full Text Available When asked to indicate which items from a set of candidates belong to a particular natural language category inter-individual differences occur: Individuals disagree which items should be considered category members. The premise of this paper is that these inter-individual differences in semantic categorization reflect both ambiguity and vagueness. Categorization differences are said to be due to ambiguity when individuals employ different criteria for categorization. For instance, individuals may disagree whether hiking or darts is the better example of sports because they emphasize respectively whether an activity is strenuous and whether rules apply. Categorization differences are said to be due to vagueness when individuals employ different cut-offs for separating members from non-members. For instance, the decision to include hiking in the sports category or not, may hinge on how strenuous different individuals require sports to be. This claim is supported by the application of a mixture model to categorization data for eight natural language categories. The mixture model can identify latent groups of categorizers who regard different items likely category members (i.e., ambiguity with categorizers within each of the groups differing in their propensity to provide membership responses (i.e., vagueness. The identified subgroups are shown to emphasize different sets of category attributes when making their categorization decisions.

  8. POSTTRAUMATIC STRESS SYMPTOMS AND AVERSION TO AMBIGUOUS LOSSES IN COMBAT VETERANS.

    Science.gov (United States)

    Ruderman, Lital; Ehrlich, Daniel B; Roy, Alicia; Pietrzak, Robert H; Harpaz-Rotem, Ilan; Levy, Ifat

    2016-07-01

    Psychiatric symptoms typically cut across traditional diagnostic categories. In order to devise individually tailored treatments, there is a need to identify the basic mechanisms that underlie these symptoms. Behavioral economics provides a framework for studying these mechanisms at the behavioral level. Here, we utilized this framework to examine a widely ignored aspect of trauma-related symptomatology-individual uncertainty attitudes-in combat veterans with and without posttraumatic stress disorder (PTSD). Fifty-seven combat veterans, including 30 with PTSD and 27 without PTSD, completed a risk and ambiguity decision-making task that characterizes individual uncertainty attitudes, distinguishing between attitudes toward uncertain outcomes with known ("risk") and unknown ("ambiguity") probabilities, and between attitudes toward uncertain gains and uncertain losses. Participants' choices were used to estimate risk and ambiguity attitudes in the gain and loss domains. Veterans with PTSD were more averse to ambiguity, but not risk, compared to veterans without PTSD, when making choices between possible losses, but not gains. The degree of aversion was associated with anxious arousal (e.g., hypervigilance) symptoms, as well as with the degree of combat exposure. Moreover, ambiguity attitudes fully mediated the association between combat exposure and anxious arousal symptoms. These results provide a foundation for prospective studies of the causal association between ambiguity attitudes and trauma-related symptoms, as well as etiologic studies of the neural underpinnings of these behavioral outcomes. More generally, these results demonstrate the potential of neuroeconomic and behavioral economic techniques for devising objective and incentive-compatible diagnostic tools, and investigating the etiology of psychiatric disorders. © 2016 Wiley Periodicals, Inc.

  9. Do you like Arcimboldo's? Esthetic appreciation modulates brain activity in solving perceptual ambiguity.

    Science.gov (United States)

    Boccia, M; Nemmi, F; Tizzani, E; Guariglia, C; Ferlazzo, F; Galati, G; Giannini, A M

    2015-02-01

    Esthetic experience is a unique, affectively colored, self-transcending subject-object relationship in which cognitive processing is felt to flow differently than during everyday experiences. Notwithstanding previous multidisciplinary investigations, how esthetic experience modulates perception is still obscure. We used Arcimboldo's ambiguous portraits to assess how the esthetic context organizes ambiguous percepts. The study was carried out using functional magnetic resonance imaging (fMRI) in healthy young volunteers (mean age 25.45; S.D. 4.51; 9 females), during both an explicit esthetic judgment task and an artwork/non-artwork classification task. We show that a distinct neural mechanism in the fusiform gyrus contributes to the esthetic experience of ambiguous portraits, according to the valence of the esthetic experience. Ambiguous artworks eliciting a negative esthetic experience lead to more pronounced activation of the fusiform face areas than ambiguous artworks eliciting a positive esthetic experience. We also found an interaction between task and ambiguity in the right superior parietal lobule. Taken together, our results demonstrate that a neural mechanism in the content-dependent brain regions of face processing underlies the esthetic experience of ambiguous portraits. Furthermore, they suggest that esthetic experience interacts with perceptual qualities of stimuli in the right superior parietal lobe, supporting the idea that esthetic experience arises from the interaction between top-down orienting of attention and bottom-up perceptual facilitation. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Wind scatterometry with improved ambiguity selection and rain modeling

    Science.gov (United States)

    Draper, David Willis

    Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributors to scatterometer estimate error: poor ambiguity selection, estimate uncertainty at low wind speeds, and rain corruption. A quality assurance (QA) analysis performed on SeaWinds data suggests that about 5% of SeaWinds data contain ambiguity selection errors and that scatterometer estimation error is correlated with low wind speeds and rain events. Ambiguity selection errors are partly due to the "nudging" step (initialization from outside data). A sophisticated new non-nudging ambiguity selection approach produces generally more consistent wind than the nudging method in moderate wind conditions. The non-nudging method selects 93% of the same ambiguities as the nudged data, validating both techniques, and indicating that ambiguity selection can be accomplished without nudging. Variability at low wind speeds is analyzed using tower-mounted scatterometer data. According to theory, below a threshold wind speed, the wind fails to generate the surface roughness necessary for wind measurement. A simple analysis suggests the existence of the threshold in much of the tower-mounted scatterometer data. However, the backscatter does not "go to zero" beneath the threshold in an uncontrolled environment as theory suggests, but rather has a mean drop and higher variability below the threshold. Rain is the largest weather-related contributor to scatterometer error, affecting approximately 4% to 10% of SeaWinds data. A simple model formed via comparison of co-located TRMM PR and SeaWinds measurements characterizes the average effect of rain on SeaWinds backscatter. The model is generally accurate to within 3 dB over the tropics. The rain/wind backscatter model is used to simultaneously retrieve wind and rain from SeaWinds measurements. The simultaneous

  11. Ambiguity Resolution for Phase-Based 3-D Source Localization under Fixed Uniform Circular Array.

    Science.gov (United States)

    Chen, Xin; Liu, Zhen; Wei, Xizhang

    2017-05-11

    Under fixed uniform circular array (UCA), 3-D parameter estimation of a source whose half-wavelength is smaller than the array aperture would suffer from a serious phase ambiguity problem, which also appears in a recently proposed phase-based algorithm. In this paper, by using the centro-symmetry of UCA with an even number of sensors, the source's angles and range can be decoupled and a novel algorithm named subarray grouping and ambiguity searching (SGAS) is addressed to resolve angle ambiguity. In the SGAS algorithm, each subarray formed by two couples of centro-symmetry sensors can obtain a batch of results under different ambiguities, and by searching the nearest value among subarrays, which is always corresponding to correct ambiguity, rough angle estimation with no ambiguity is realized. Then, the unambiguous angles are employed to resolve phase ambiguity in a phase-based 3-D parameter estimation algorithm, and the source's range, as well as more precise angles, can be achieved. Moreover, to improve the practical performance of SGAS, the optimal structure of subarrays and subarray selection criteria are further investigated. Simulation results demonstrate the satisfying performance of the proposed method in 3-D source localization.

  12. Dispositional sources of sanction perceptions: Emotionality, cognitive style, intolerance of ambiguity, and self-efficacy.

    Science.gov (United States)

    Pickett, Justin T; Bushway, Shawn D

    2015-12-01

    This study contributes to efforts to identify the sources of arrest risk perceptions and ambiguity (or lack of confidence) in such perceptions. Drawing on dual-process theories of reasoning, we argue that arrest risk perceptions often represent intuitive judgments that are influenced by cognitive heuristics and dispositional attributes. Multivariate regression models are estimated with data from 3 national surveys to test 6 hypotheses about the relationships between specific dispositional attributes and perceived arrest risk and ambiguity. We find evidence that dispositional positive affect and intolerance of ambiguity are both positively related to perceived arrest risk, and are also both negatively related to ambiguity. We also find evidence that cognitive reflection and general self-efficacy are, respectively, positively and negatively associated with ambiguity. Mixed evidence emerges about whether cognitive reflection is related to risk perceptions, and about whether either dispositional negative affect or thoughtfully reflective decision making correlate with ambiguity. Taken together, the results provide partial support for each of our hypotheses, and suggest that dispositional attributes are important sources of perceptions of arrest risk as well as of ambiguity in such perceptions. (c) 2015 APA, all rights reserved).

  13. Motion discrimination under uncertainty and ambiguity.

    NARCIS (Netherlands)

    Kalisvaart, J.P.; Klaver, I.; Goossens, J.

    2011-01-01

    Speed and accuracy of visual motion discrimination depend systematically on motion strength. This behavior is traditionally explained by diffusion models that assume accumulation of sensory evidence over time to a decision bound. However, how does the brain decide when sensory evidence is ambiguous,

  14. A New Block Processing Algorithm of LLL for Fast High-dimension Ambiguity Resolution

    Directory of Open Access Journals (Sweden)

    LIU Wanke

    2016-02-01

    Full Text Available Due to high dimension and precision for the ambiguity vector under GNSS observations of multi-frequency and multi-system, a major problem to limit computational efficiency of ambiguity resolution is the longer reduction time when using conventional LLL algorithm. To address this problem, it is proposed a new block processing algorithm of LLL by analyzing the relationship between the reduction time and the dimensions and precision of ambiguity. The new algorithm reduces the reduction time to improve computational efficiency of ambiguity resolution, which is based on block processing ambiguity variance-covariance matrix that decreased the dimensions of single reduction matrix. It is validated that the new algorithm with two groups of measured data. The results show that the computing efficiency of the new algorithm increased by 65.2% and 60.2% respectively compared with that of LLL algorithm when choosing a reasonable number of blocks.

  15. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  16. A Range Ambiguity Suppression Processing Method for Spaceborne SAR with Up and Down Chirp Modulation.

    Science.gov (United States)

    Wen, Xuejiao; Qiu, Xiaolan; Han, Bing; Ding, Chibiao; Lei, Bin; Chen, Qi

    2018-05-07

    Range ambiguity is one of the factors which affect the SAR image quality. Alternately transmitting up and down chirp modulation pulses is one of the methods used to suppress the range ambiguity. However, the defocusing range ambiguous signal can still hold the stronger backscattering intensity than the mainlobe imaging area in some case, which has a severe impact on visual effects and subsequent applications. In this paper, a novel hybrid range ambiguity suppression method for up and down chirp modulation is proposed. The method can obtain the ambiguity area image and reduce the ambiguity signal power appropriately, by applying pulse compression using a contrary modulation rate and CFAR detecting method. The effectiveness and correctness of the approach is demonstrated by processing the archive images acquired by Chinese Gaofen-3 SAR sensor in full-polarization mode.

  17. Making sense of employer collectivism

    DEFF Research Database (Denmark)

    Ibsen, Christian Lyhne

    2016-01-01

    This conceptual article argues that preferences of employers for collective action cannot be reduced to rational actors making decisions based on market structures or institutional logics. Both markets and institutions are inherently ambiguous and employers therefore have to settle for plausible...... – rather than accurate – rational strategies among many alternatives through so-called sensemaking. Sensemaking refers to the process by which employers continuously make sense of their competitive environment by building causal stories of competitive advantages. The article therefore tries to provide......, unlike countries in similar situations, for example Finland and Sweden, Danish employers retained a coordinated industry-level bargaining system, which makes it an interesting paradox to study from the vantage point of sensemaking....

  18. More than visual literacy: art and the enhancement of tolerance for ambiguity and empathy.

    Science.gov (United States)

    Bentwich, Miriam Ethel; Gilbey, Peter

    2017-11-10

    Comfort with ambiguity, mostly associated with the acceptance of multiple meanings, is a core characteristic of successful clinicians. Yet past studies indicate that medical students and junior physicians feel uncomfortable with ambiguity. Visual Thinking Strategies (VTS) is a pedagogic approach involving discussions of art works and deciphering the different possible meanings entailed in them. However, the contribution of art to the possible enhancement of the tolerance for ambiguity among medical students has not yet been adequately investigated. We aimed to offer a novel perspective on the effect of art, as it is experienced through VTS, on medical students' tolerance of ambiguity and its possible relation to empathy. Quantitative method utilizing a short survey administered after an interactive VTS session conducted within mandatory medical humanities course for first-year medical students. The intervention consisted of a 90-min session in the form of a combined lecture and interactive discussions about art images. The VTS session and survey were filled by 67 students in two consecutive rounds of first-year students. 67% of the respondents thought that the intervention contributed to their acceptance of multiple possible meanings, 52% thought their visual observation ability was enhanced and 34% thought that their ability to feel the sufferings of other was being enhanced. Statistically significant moderate-to-high correlations were found between the contribution to ambiguity tolerance and contribution to empathy (0.528-0.744; p ≤ 0.01). Art may contribute especially to the development of medical students' tolerance of ambiguity, also related to the enhancement of empathy. The potential contribution of visual art works used in VTS to the enhancement of tolerance for ambiguity and empathy is explained based on relevant literature regarding the embeddedness of ambiguity within art works, coupled with reference to John Dewey's theory of learning. Given the

  19. Strategic ambiguities in the process of consent: role of the family in decisions to forgo life-sustaining treatment for incompetent elderly patients.

    Science.gov (United States)

    Tse, Chun-yan; Tao, Julia; Chun-yan, Tse

    2004-04-01

    This paper evaluates the Hong Kong approach to consent regarding the forgoing of life-sustaining treatment for incompetent elderly patients. It analyzes the contextualized approach in the Hong Kong process-based, consensus-building model, in contrast to other role-based models which emphasize the establishment of a system of formal laws and a clear locus of decisional authority. Without embracing relativism, the paper argues that the Hong Kong model offers an instructive example of how strategic ambiguities can both make good sense within particular cultural context and serve important moral goals.

  20. A Range Ambiguity Suppression Processing Method for Spaceborne SAR with Up and Down Chirp Modulation

    Directory of Open Access Journals (Sweden)

    Xuejiao Wen

    2018-05-01

    Full Text Available Range ambiguity is one of the factors which affect the SAR image quality. Alternately transmitting up and down chirp modulation pulses is one of the methods used to suppress the range ambiguity. However, the defocusing range ambiguous signal can still hold the stronger backscattering intensity than the mainlobe imaging area in some case, which has a severe impact on visual effects and subsequent applications. In this paper, a novel hybrid range ambiguity suppression method for up and down chirp modulation is proposed. The method can obtain the ambiguity area image and reduce the ambiguity signal power appropriately, by applying pulse compression using a contrary modulation rate and CFAR detecting method. The effectiveness and correctness of the approach is demonstrated by processing the archive images acquired by Chinese Gaofen-3 SAR sensor in full-polarization mode.

  1. Is ambiguity tolerance malleable? Experimental evidence with potential implications for future research.

    Science.gov (United States)

    Endres, Megan L; Camp, Richaurd; Milner, Morgan

    2015-01-01

    We conducted two research studies to address the malleability of tolerance of ambiguity (TA) by manipulating situational ambiguity. Students participated in a semester-end assessment of their management skills (n = 306). In Study 1, students in low and moderate ambiguity conditions had significantly higher post-experiment TA, more positive change in self-efficacy, and marginally higher faculty ratings. In Study 2, a control group (n = 103) did not participate in the assessment and was established for comparison to the first study results. The Study 2 students reported TA significantly lower than Study 1 students in the low and moderate ambiguity conditions. The control group TA was not significantly different from that of the Study 1 high ambiguity condition. This further suggested TA's situational malleability, as those who had controlled access to structured information appeared to have increased their TA over that observed in the other two groups. These results suggest that TA may be malleable. We review the relevant literature, offer hypotheses, report our analyses and findings, and then propose future research, and potential prescriptive applications in such areas as management development, assessment, and decision-making.

  2. Size doesn't really matter: ambiguity aversion in Ellsberg urns with few balls.

    Science.gov (United States)

    Pulford, Briony D; Colman, Andrew M

    2008-01-01

    When attempting to draw a ball of a specified color either from an urn containing 50 red balls and 50 black balls or from an urn containing an unknown ratio of 100 red and black balls, a majority of decision makers prefer the known-risk urn, and this ambiguity aversion effect violates expected utility theory. In an experimental investigation of the effect of urn size on ambiguity aversion, 149 participants showed similar levels of aversion when choosing from urns containing 2, 10, or 100 balls. The occurrence of a substantial and significant ambiguity aversion effect even in the smallest urn suggests that influential theoretical interpretations of ambiguity aversion may need to be reconsidered.

  3. Compressive sensing for sparse time-frequency representation of nonstationary signals in the presence of impulsive noise

    Science.gov (United States)

    Orović, Irena; Stanković, Srdjan; Amin, Moeness

    2013-05-01

    A modified robust two-dimensional compressive sensing algorithm for reconstruction of sparse time-frequency representation (TFR) is proposed. The ambiguity function domain is assumed to be the domain of observations. The two-dimensional Fourier bases are used to linearly relate the observations to the sparse TFR, in lieu of the Wigner distribution. We assume that a set of available samples in the ambiguity domain is heavily corrupted by an impulsive type of noise. Consequently, the problem of sparse TFR reconstruction cannot be tackled using standard compressive sensing optimization algorithms. We introduce a two-dimensional L-statistics based modification into the transform domain representation. It provides suitable initial conditions that will produce efficient convergence of the reconstruction algorithm. This approach applies sorting and weighting operations to discard an expected amount of samples corrupted by noise. The remaining samples serve as observations used in sparse reconstruction of the time-frequency signal representation. The efficiency of the proposed approach is demonstrated on numerical examples that comprise both cases of monocomponent and multicomponent signals.

  4. Inherent ambiguities in the determination of phase-shifts

    International Nuclear Information System (INIS)

    Atkinson, D.

    1975-01-01

    The observables in an elastic scattering process are unchanged if all the scattering amplitudes are multiplied by the same angle-dependent phase. The non-spin-flip and spin-flip amplitudes remain unchanged by the substitution: g(cos theta)→g(cos theta)exp[i phi(cos theta)] and h(cos theta)→h(cos theta)exp[i phi(cos theta)]. Unless some extra and hoc assumption is made, there is a continuum ambiguity, which has been explored some time ago, with specific models for the phase phi by members of the Birmingham group. In the ordinary quantum mechanics of scattering, one writes a wave-function asymptotically as psi(r - ) approximately esup(ikr costheta)+f(cos theta)esup(ikr)/r where f is the scattering amplitude. The ambiguity which is a change in the phase of the scattering amplitude, and thus of the scattered part of the wavefunction, but with no change of the first term in (the unscattered plane wave coming along the z-axis is discussed in detail. Preliminary results in the energy-range 1550-1750 MeV cm and their implications are given. Argand plots of ambiguities at various energies are presented. (K.B.)

  5. Exploiting Lexical Ambiguity to Help Students Understand the Meaning of "Random"

    Science.gov (United States)

    Kaplan, Jennifer J.; Rogness, Neal T.; Fisher, Diane G.

    2014-01-01

    Words that are part of colloquial English but used differently in a technical domain may possess lexical ambiguity. The use of such words by instructors may inhibit student learning if incorrect connections are made by students between the technical and colloquial meanings. One fundamental word in statistics that has lexical ambiguity for students…

  6. Aggregating imprecise or conflicting beliefs: An experimental investigation using modern ambiguity theories

    NARCIS (Netherlands)

    A. Baillon (Aurélien); L. Cabantous (Laure); P.P. Wakker (Peter)

    2012-01-01

    textabstractTwo experiments show that violations of expected utility due to ambiguity, found in general decision experiments, also affect belief aggregation. Hence we use modern ambiguity theories to analyze belief aggregation, thus obtaining more refined and empirically more valid results than

  7. ROLE CONFLICT AND ROLE AMBIGUITY ON LOCAL GOVERNMENT INTERNAL AUDITORS: THE DETERMINANT AND IMPACTS

    Directory of Open Access Journals (Sweden)

    Agil Novriansa

    2016-01-01

    Full Text Available The bureaucratic reform at the local government level in Indonesia that was instituted in 2012 has turned local government internal auditors into an important part of government governance systems. The role of local government internal auditors has been expanded to include not only the area of audit oversight, but also the areas of anti-corruption-related and consulting activities. These fundamental changes may potentially induce role conflict and role ambiguity among internal auditors. The objective of this study is to examine empirically the determinants and consequences of role conflict and role ambiguity among local government internal auditors. More specifically, this study attempts to examine the extent to which formalization determines role conflict and role ambiguity; it further tests the impact of role conflict and role ambiguity on commitment to independence and job performance. Questionnaires were distributed to 248 local government internal auditors from 12 Regional Inspectorates in the provinces of Yogyakarta, South Sumatra, and East Java. A total of 176 responses were received, and 124 useable responses from the 176 responses were analysed to test the hypotheses. Using Structural Equation Modelling-Partial Least Square the results show that: formalization is negatively related to role conflict and role ambiguity; role ambiguity has a negative impact on commitment to independence; role conflict has a positive impact on job performance; and role ambiguity has a negative impact on job performance. These findings serve as important external validity evidence on the phenomena associated with role conflict and role ambiguity that occur in the public sector, especially among internal auditors at local government institutions.

  8. The skew ray ambiguity in the analysis of videokeratoscopic data.

    Science.gov (United States)

    Iskander, D Robert; Davis, Brett A; Collins, Michael J

    2007-05-01

    Skew ray ambiguity is present in most videokeratoscopic measurements when azimuthal components of the corneal curvature are not taken into account. There have been some reported studies based on theoretical predictions and measured test surfaces suggesting that skew ray ambiguity is significant for highly deformed corneas or decentered corneal measurements. However, the effect of skew ray ambiguity in ray tracing through videokeratoscopic data has not been studied in depth. We have evaluated the significance of the skew ray ambiguity and its effect on the analyzed corneal optics. This has been achieved by devising a procedure in which we compared the corneal wavefront aberrations estimated from 3D ray tracing with those determined from 2D (meridional based) estimates of the refractive power. The latter was possible due to recently developed concept of refractive Zernike power polynomials which links the refractive power domain with that of the wavefront. Simulated corneal surfaces as well as data from a range of corneas (from two different Placido disk-based videokeratoscopes) were used to find the limit at which the difference in estimated corneal wavefronts (or the corresponding refractive powers) would have clinical significance (e.g., equivalent to 0.125 D or more). The inclusion/exclusion of the skew ray in the analyses showed some differences in the results. However, the proposed procedure showed clinically significant differences only for highly deformed corneas and only for large corneal diameters. For the overwhelming majority of surfaces, the skew ray ambiguity is not a clinically significant issue in the analysis of the videokeratoscopic data indicating that the meridional processing such as that encountered in calculation of the refractive power maps is adequate.

  9. The role of ambiguity and discrepancy in the early phases of innovation

    DEFF Research Database (Denmark)

    Laursen, Linda Nhu; Tollestrup, Christian H. T.

    2015-01-01

    Innovation literature mainly focuses on eliminating ambiguity and discrepancy from the early phases of innovation. This study questions this implicit assumption, as it may provide an oversimplified view on, how to attain proficiency. Instead of narrowly focusing on reducing ambiguity and discrepa...

  10. More is not always better: coping with ambiguity in natural resources management

    NARCIS (Netherlands)

    Brugnach, M.; Dewulf, A.; Henriksen, H.J.; Keur, van der P.

    2011-01-01

    Coping with ambiguities in natural resources management has become unavoidable. Ambiguity is a distinct type of uncertainty that results from the simultaneous presence of multiple valid, and sometimes conflicting, ways of framing a problem. As such, it reflects discrepancies in meanings and

  11. More is not always better: Coping with ambiguity in natural resources management

    NARCIS (Netherlands)

    Brugnach, Marcela Fabiana; De Wulf, A.; Henriksen, H.J.; van der Keur, P.

    2011-01-01

    Coping with ambiguities in natural resources management has become unavoidable. Ambiguity is a distinct type of uncertainty that results from the simultaneous presence of multiple valid, and sometimes conflicting, ways of framing a problem. As such, it reflects discrepancies in meanings and

  12. Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

    Science.gov (United States)

    Wimmer, Marina C; Stirk, Steven; Hancock, Peter J B

    2017-10-01

    This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

  13. Task Characteristics and Work Engagement: Exploring Effects of Role Ambiguity and ICT Presenteeism

    Directory of Open Access Journals (Sweden)

    Sang-Hoon Lee

    2017-10-01

    Full Text Available In order to secure organizational sustainability in a rapidly changing environment, it is necessary to implement a decentralized and flexible work environment. In such work environments, normally individuals are provided with autonomy and independence in performing tasks, thus allowing them to further engage in their given work. This study investigated task antecedents of work engagement, and further explored the process of how task characteristics affect work engagement. It focused on examining the mediating effect of role ambiguity on the task characteristics-work engagement relationship and the moderating effect of information and communication technology (ICT presenteeism on the task characteristics–role ambiguity relationship through multiple regression analyses and a bootstrapping procedure on survey data collected from 202 South Korean employees. It found that task interdependence and autonomy were negatively associated with role ambiguity. Of the two task characteristics, only task interdependence had a negative relationship with role ambiguity, and this relationship was significantly moderated by ICT presenteeism such that the negative association between task interdependence and role ambiguity was more pronounced when ICT presenteeism was high than when it was low.

  14. Ambiguities of theoretical parameters and CP or T violation in neutrino factories

    International Nuclear Information System (INIS)

    Koike, Masafumi; Ota, Toshihiko; Sato, Joe

    2002-01-01

    We study the sensitivity to the CP- or T-violation search in the presence of ambiguities of the theoretical parameters. Three generations of neutrinos are considered. The parameters whose ambiguities are considered are the differences of the squared masses, the mixing angles, and the density of matter. We first consider the statistics that are sensitive to the genuine CP-violation effect originating from the imaginary coupling. No ambiguity of the parameters is considered in this part. It is argued that the widely adopted usual statistics are not necessarily sensitive to the genuine CP-violation effect. Two statistics that are sensitive to the imaginary coupling are proposed. The qualitative difference between these statistics and the usual ones are discussed. Next we proceed to the case where the ambiguity of the parameters is present. The sensitivity of the CP-violation search is greatly spoiled when the baseline length is longer than about one thousand kilometers, which turns out to be due to the ambiguity of the matter effect. Thus the CP-violation search by use of CP conjugate channels turns out to require a low energy neutrino and short baseline length. It is also shown that such a loss of sensitivity is avoided by using T-conjugate oscillation channels

  15. Role conflict, role ambiguity and job satisfaction: Perceptions of the Brazilian controllers

    Directory of Open Access Journals (Sweden)

    Marilu Nuñez Palomino

    2016-06-01

    Full Text Available ABSTRACT From early times to the present, accounting literature has recorded several situations involving role conflict and ambiguity that cause tension among controllers. The theoretical framework was comprised of the seminal work on Role Theory by Katz and Kahn (1970, and empirical evidence regarding the evolution of the role of controllers in the enterprises. In this study, we used the structural equations technique, which allowed for non-rejection of the two study hypotheses, thus providing evidence that role conflict and ambiguity adversely affect job satisfaction among Brazilian controllers. The sample was comprised of 114 controllers. An electronic questionnaire was used to collect the data, allowing information about the respondents to be captured, along with their perceptions regarding levels of role conflict and ambiguity and job satisfaction. For this, the tools developed by Rizzo, House, and Lirtzman (1970 were used, as well as the Job Satisfaction Index presented by Tarrant and Sabo (2010. The results indicated that Brazilian controllers perceive role conflict and role ambiguity while they perform their duties. Job satisfaction of the controllers isaffected more strongly by role ambiguity than by role conflict. However, despite perceiving these two tensions, executives are moderately satisfied with their current working conditions.

  16. The inertial attitude augmentation for ambiguity resolution in SF/SE-GNSS attitude determination.

    Science.gov (United States)

    Zhu, Jiancheng; Hu, Xiaoping; Zhang, Jingyu; Li, Tao; Wang, Jinling; Wu, Meiping

    2014-06-26

    The Unaided Single Frequency/Single Epoch Global Navigation Satellite System (SF/SE GNSS) model is the most challenging scenario for ambiguity resolution in the GNSS attitude determination application. To improve the performance of SF/SE-GNSS ambiguity resolution without excessive cost, the Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS-IMU) is a proper choice for the auxiliary sensor that carries out the inertial attitude augmentation. Firstly, based on the SF/SE-GNSS compass model, the Inertial Derived Baseline Vector (IDBV) is defined to connect the MEMS-IMU attitude measurement with the SF/SE-GNSS ambiguity search space, and the mechanism of inertial attitude augmentation is revealed from the perspective of geometry. Then, through the quantitative description of model strength by Ambiguity Dilution of Precision (ADOP), two ADOPs are specified for the unaided SF/SE-GNSS compass model and its inertial attitude augmentation counterparts, respectively, and a sufficient condition is proposed for augmenting the SF/SE-GNSS model strength with inertial attitude measurement. Finally, in the framework of an integer aperture estimator with fixed failure rate, the performance of SF/SE-GNSS ambiguity resolution with inertial attitude augmentation is analyzed when the model strength is varying from strong to weak. The simulation results show that, in the SF/SE-GNSS attitude determination application, MEMS-IMU can satisfy the requirements of ambiguity resolution with inertial attitude augmentation.

  17. The Inertial Attitude Augmentation for Ambiguity Resolution in SF/SE-GNSS Attitude Determination

    Science.gov (United States)

    Zhu, Jiancheng; Hu, Xiaoping; Zhang, Jingyu; Li, Tao; Wang, Jinling; Wu, Meiping

    2014-01-01

    The Unaided Single Frequency/Single Epoch Global Navigation Satellite System (SF/SE GNSS) model is the most challenging scenario for ambiguity resolution in the GNSS attitude determination application. To improve the performance of SF/SE-GNSS ambiguity resolution without excessive cost, the Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS-IMU) is a proper choice for the auxiliary sensor that carries out the inertial attitude augmentation. Firstly, based on the SF/SE-GNSS compass model, the Inertial Derived Baseline Vector (IDBV) is defined to connect the MEMS-IMU attitude measurement with the SF/SE-GNSS ambiguity search space, and the mechanism of inertial attitude augmentation is revealed from the perspective of geometry. Then, through the quantitative description of model strength by Ambiguity Dilution of Precision (ADOP), two ADOPs are specified for the unaided SF/SE-GNSS compass model and its inertial attitude augmentation counterparts, respectively, and a sufficient condition is proposed for augmenting the SF/SE-GNSS model strength with inertial attitude measurement. Finally, in the framework of an integer aperture estimator with fixed failure rate, the performance of SF/SE-GNSS ambiguity resolution with inertial attitude augmentation is analyzed when the model strength is varying from strong to weak. The simulation results show that, in the SF/SE-GNSS attitude determination application, MEMS-IMU can satisfy the requirements of ambiguity resolution with inertial attitude augmentation. PMID:24971472

  18. Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance.

    Science.gov (United States)

    Mañas, Miguel A; Díaz-Fúnez, Pedro; Pecino, Vicente; López-Liria, Remedios; Padilla, David; Aguilar-Parra, José M

    2017-01-01

    In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate). In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context.

  19. Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance

    Science.gov (United States)

    Mañas, Miguel A.; Díaz-Fúnez, Pedro; Pecino, Vicente; López-Liria, Remedios; Padilla, David; Aguilar-Parra, José M.

    2018-01-01

    In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate). In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context. PMID:29375424

  20. Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance

    Directory of Open Access Journals (Sweden)

    Miguel A. Mañas

    2018-01-01

    Full Text Available In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate. In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context.

  1. Athletes' perceptions of role ambiguity and coaching competency in sport teams: a multilevel analysis.

    Science.gov (United States)

    Bosselut, Grégoire; Heuzé, Jean-Philippe; Eys, Mark A; Fontayne, Paul; Sarrazin, Philippe

    2012-06-01

    The purpose of this study was to examine the relationship between athletes' perceptions of role ambiguity and two theoretically derived dimensions of coaching competency (i.e., game strategy and technique competencies). A total of 243 players from 26 teams representing various interdependent sports completed French versions of the Role Ambiguity Scale and the Coaching Competency Scale. Multilevel analyses supported the existence of relationships between the four dimensions of role ambiguity and the two dimensions of coaching competency at both individual and team levels. When the levels were considered jointly, athletes perceiving greater ambiguity in their role in both offensive and defensive contexts were more critical of their coach's capacities to lead their team during competitions and to diagnose or formulate instructions during training sessions. The results also indicated that the dimension of scope of responsibilities was the main contributor to the relationship with coaching competency at an individual level, whereas role evaluation was the main contributor to this relationship at a group level. Findings are discussed in relation to the role episode model, the role ambiguity dimensions involved in the relationships according to the level of analysis considered, and the salience of ambiguity perceptions in the offensive context.

  2. Measuring the ambiguity tolerance of medical students: a cross-sectional study from the first to sixth academic years.

    Science.gov (United States)

    Weissenstein, Anne; Ligges, Sandra; Brouwer, Britta; Marschall, Bernhard; Friederichs, Hendrik

    2014-01-09

    Tolerance of ambiguity, or the extent to which ambiguous situations are perceived as desirable, is an important component of the attitudes and behaviors of medical students. However, few studies have compared this trait across the years of medical school. General practitioners are considered to have a higher ambiguity tolerance than specialists. We compared ambiguity tolerance between general practitioners and medical students. We designed a cross-sectional study to evaluate the ambiguity tolerance of 622 medical students in the first to sixth academic years. We compared this with the ambiguity tolerance of 30 general practitioners. We used the inventory for measuring ambiguity tolerance (IMA) developed by Reis (1997), which includes three measures of ambiguity tolerance: openness to new experiences, social conflicts, and perception of insoluble problems. We obtained a total of 564 complete data sets (return rate 90.1%) from medical students and 29 questionnaires (return rate 96.7%) from general practitioners. In relation to the reference groups defined by Reis (1997), medical students had poor ambiguity tolerance on all three scales. No differences were found between those in the first and the sixth academic years, although we did observe gender-specific differences in ambiguity tolerance. We found no differences in ambiguity tolerance between general practitioners and medical students. The ambiguity tolerance of the students that we assessed was below average, and appeared to be stable throughout the course of their studies. In contrast to our expectations, the general practitioners did not have a higher level of ambiguity tolerance than the students did.

  3. The Relationship between Tolerance of Ambiguity and Stereotyping: Implications for BSW Education

    Science.gov (United States)

    Valutis, Stephanie A.

    2015-01-01

    Ambiguity tolerance and intolerance can influence one's professional practice. The study of such influences remains sparse within the social work literature. Behaviors that reduce uncertainty, including categorizing or stereotyping, are used by those who feel discomfort in ambiguous situations. This study explores explore the relationship between…

  4. Ambiguous Belonging and the Challenge of Inclusion: Parent Perspectives on School Membership

    Science.gov (United States)

    Scorgie, Kate

    2015-01-01

    Boundary ambiguity occurs when members of a family are confused or uncertain regarding roles, responsibilities and subsystem configurations within the family. Research suggests that perception of boundary ambiguity is associated with family stress despite internal and external resource availability. It has been suggested that research on family…

  5. Acute stress affects risk taking but not ambiguity aversion.

    Science.gov (United States)

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  6. Space-frequency analysis and reduction of potential field ambiguity

    Directory of Open Access Journals (Sweden)

    A. Rapolla

    1997-06-01

    Full Text Available Ambiguity of depth estimation of magnetic sources via spectral analysis can be reduced representing its field via a set of space-frequency atoms. This is obtained throughout a continuous wavelet transform using a Morlet analyzing wavelet. In the phase-plane representation even a weak contribution related to deep-seated sources is clearly distinguished with respect a more intense effect of a shallow source, also in the presence of a strong noise. Furthermore, a new concept of local power spectrum allows the depth to both the sources to be correctly interpreted. Neither result can be provided by standard Fourier analysis. Another method is proposed to reduce ambiguity by inversion of potential field data lying along the vertical axis. This method allows a depth resolution to gravity or the magnetic methods and below some conditions helps to reduce their inherent ambiguity. Unlike the case of monopoles, inversion of a vertical profile of gravity data above a cubic source gives correct results for the cube side and density.

  7. Perceptions of boundary ambiguity in the process of leaving an abusive partner.

    Science.gov (United States)

    Khaw, Lyndal; Hardesty, Jennifer L

    2015-06-01

    The process of leaving an abusive partner has been theorized using the Stages of Change Model. Although useful, this model does not account for changes in relational boundaries unique to the process of leaving. Using family stress and feminist perspectives, this study sought to integrate boundary ambiguity into the Stages of Change Model. Boundary ambiguity is defined as a perception of uncertainty as to who is in or out of a family system (Boss & Greenberg, 1984). Twenty-five mothers who had temporarily or permanently left their abusers were interviewed. Data were analyzed using constructivist grounded theory methods. Results identify types, indicators of, and mothers' responses to boundary ambiguity throughout the five stages of change. Most mothers and abusers fluctuated between physical and psychological presence and absence over multiple separations. The integration of boundary ambiguity into the Stages of Change Model highlights the process of leaving an abusive partner as systemic, fluid, and nonlinear. © 2014 Family Process Institute.

  8. Cross-linguistic scope ambiguity: When two systems meet

    Directory of Open Access Journals (Sweden)

    Gregory Scontras

    2017-04-01

    Full Text Available Accurately recognizing and resolving ambiguity is a hallmark of linguistic ability. English is a language with scope ambiguities in doubly-quantified sentences like 'A shark ate every pirate'; this sentence can either describe a scenario with a single shark eating all of the pirates, or a scenario with many sharks—a potentially-different one eating each pirate. In Mandarin Chinese, the corresponding sentence is unambiguous, as it can only describe the single-shark scenario. We present experimental evidence to this effect, comparing native speakers of English with native speakers of Mandarin in their interpretations of doubly-quantified sentences. Having demonstrated the difference between these two languages in their ability for inverse scope interpretations, we then probe the robustness of the grammar of scope by extending our experiments to English-dominant adult heritage speakers of Mandarin. Like native speakers of Mandarin, heritage Mandarin speakers lack inverse scope in Mandarin. Crucially, these speakers also lack inverse scope in English, their dominant language in adulthood. We interpret these results as evidence for the pressure to simplify the grammar of scope, decreasing ambiguity when possible. In other words, when two systems meet—as in the case of heritage speakers—the simpler system prevails. This article is part of the special collection: Quantifier Scope

  9. Authoritarianism, cognitive rigidity, and the processing of ambiguous visual information.

    Science.gov (United States)

    Duncan, Lauren E; Peterson, Bill E

    2014-01-01

    Intolerance of ambiguity and cognitive rigidity are unifying aspects of authoritarianism as defined by Adorno, Frenkel-Brunswik, Levinson, and Sanford (1982/1950), who hypothesized that authoritarians view the world in absolute terms (e.g., good or evil). Past studies have documented the relationship between authoritarianism and intolerance of ambiguity and rigidity. Frenkel-Brunswik (1949) hypothesized that this desire for absolutism was rooted in perceptual processes. We present a study with three samples that directly tests the relationship between right wing authoritarianism (RWA) and the processing of ideologically neutral but ambiguous visual stimuli. As hypothesized, in all three samples we found that RWA was related to the slower processing of visual information that required participants to recategorize objects. In a fourth sample, RWA was unrelated to speed of processing visual information that did not require recategorization. Overall, results suggest a relationship between RWA and rigidity in categorization.

  10. Ambiguity assessment of small-angle scattering curves from monodisperse systems.

    Science.gov (United States)

    Petoukhov, Maxim V; Svergun, Dmitri I

    2015-05-01

    A novel approach is presented for an a priori assessment of the ambiguity associated with spherically averaged single-particle scattering. The approach is of broad interest to the structural biology community, allowing the rapid and model-independent assessment of the inherent non-uniqueness of three-dimensional shape reconstruction from scattering experiments on solutions of biological macromolecules. One-dimensional scattering curves recorded from monodisperse systems are nowadays routinely utilized to generate low-resolution particle shapes, but the potential ambiguity of such reconstructions remains a major issue. At present, the (non)uniqueness can only be assessed by a posteriori comparison and averaging of repetitive Monte Carlo-based shape-determination runs. The new a priori ambiguity measure is based on the number of distinct shape categories compatible with a given data set. For this purpose, a comprehensive library of over 14,000 shape topologies has been generated containing up to seven beads closely packed on a hexagonal grid. The computed scattering curves rescaled to keep only the shape topology rather than the overall size information provide a `scattering map' of this set of shapes. For a given scattering data set, one rapidly obtains the number of neighbours in the map and the associated shape topologies such that in addition to providing a quantitative ambiguity measure the algorithm may also serve as an alternative shape-analysis tool. The approach has been validated in model calculations on geometrical bodies and its usefulness is further demonstrated on a number of experimental X-ray scattering data sets from proteins in solution. A quantitative ambiguity score (a-score) is introduced to provide immediate and convenient guidance to the user on the uniqueness of the ab initio shape reconstruction from the given data set.

  11. Three-frequency BDS precise point positioning ambiguity resolution based on raw observables

    Science.gov (United States)

    Li, Pan; Zhang, Xiaohong; Ge, Maorong; Schuh, Harald

    2018-02-01

    All BeiDou navigation satellite system (BDS) satellites are transmitting signals on three frequencies, which brings new opportunity and challenges for high-accuracy precise point positioning (PPP) with ambiguity resolution (AR). This paper proposes an effective uncalibrated phase delay (UPD) estimation and AR strategy which is based on a raw PPP model. First, triple-frequency raw PPP models are developed. The observation model and stochastic model are designed and extended to accommodate the third frequency. Then, the UPD is parameterized in raw frequency form while estimating with the high-precision and low-noise integer linear combination of float ambiguity which are derived by ambiguity decorrelation. Third, with UPD corrected, the LAMBDA method is used for resolving full or partial ambiguities which can be fixed. This method can be easily and flexibly extended for dual-, triple- or even more frequency. To verify the effectiveness and performance of triple-frequency PPP AR, tests with real BDS data from 90 stations lasting for 21 days were performed in static mode. Data were processed with three strategies: BDS triple-frequency ambiguity-float PPP, BDS triple-frequency PPP with dual-frequency (B1/B2) and three-frequency AR, respectively. Numerous experiment results showed that compared with the ambiguity-float solution, the performance in terms of convergence time and positioning biases can be significantly improved by AR. Among three groups of solutions, the triple-frequency PPP AR achieved the best performance. Compared with dual-frequency AR, additional the third frequency could apparently improve the position estimations during the initialization phase and under constraint environments when the dual-frequency PPP AR is limited by few satellite numbers.

  12. AMBIGUITY OF LOCI DURING HLA-TYPING ON SSO TECHNOLOGY AND ATTEMPT TO RESOLVE THEM

    Directory of Open Access Journals (Sweden)

    M. A. Loginova

    2010-01-01

    Full Text Available Sequence specific oligonucleotides typing was used to identify human leukocyte antigen (HLA-A, B, DRB1 alleles from 705 recruited volunteers with Volga Federal District for unrelated hematopoietic stem cell registry and 155 of their number at locus HLA-C. 48 samples cannot be entered into the database because of ambiguities in the identification of allelic loci on HLA-class I – HLA-A, HLA-B. To resolution of ambiguity use reagents kits AlleleSEQR HLA Sequencing, which allowed to reveal the ambiguity of the locus HLA-A, 44% of cases, the loci HLA-B and HLA-C – 40% of cases. Application software HARPs Finder showed the possibility of resolution of all identified allelic ambiguities (with the exception of types of ambiguity – A*03/A*32 or A*74:13/A*32:04 and A*01/A*11 or A*36:04/A*11 with the addition of basic kits AlleleSEQR HLA Sequencing reagents kit Al- leleSEQR HARPs. 

  13. Diffeomorphisms, Anomalies and the Fefferman-Graham Ambiguity

    International Nuclear Information System (INIS)

    Schwimmer, A.; Theisen, S.

    2000-01-01

    Using the Weyl transfomations induced by diffeomorphisms we set up a cohomological problem for the Fefferman-Graham coefficients. The cohomologically nontrivial solutions remove the ambiguity and give the nonlocal terms in the effective action responsible for the trace anomalies. (author)

  14. Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

    DEFF Research Database (Denmark)

    Munk, Claus; Rubtsov, Alexey Vladimirovich

    We solve a stock-bond-cash portfolio choice problem for a risk- and ambiguity-averse investor in a setting where the inflation rate and interest rates are stochastic. The expected inflation rate is unobservable, but the investor may learn about it from realized inflation and observed stock and bond......-Jacobi-Bellman equation in closed form and derive and illustrate a number of interesting properties of the solution. For example, ambiguity aversion affects the optimal portfolio through the correlation of price level with the stock index, a bond, and the expected inflation rate. Furthermore, unlike other settings...

  15. Quantum-mechanical analysis of the VRsup(n) ambiguity in the optical model

    International Nuclear Information System (INIS)

    Shastry, C.S.

    1982-01-01

    Using analytical methods and without adopting numerical calculations or semiclassical arguments, it is shown that the well known VRsup(n), n is approximately equal to 2, parameter ambiguity in the neutron-nucleus optical potential can be attributed to the closeness of the Woods-Saxon potential to the corresponding square well inside the nucleus. This parameter ambiguity is absent in individual partial waves but is more apparent in the differential cross section. The analysis is generalised to the proton-nucleus optical model. The present method clearly pinpoints the mathematical origin of the VRsup(n) ambiguity which is difficult to deduce by purely numerical methods. (author)

  16. The Ambiguity of Justice: Paul Ricoeur on Universalism and Evil

    Directory of Open Access Journals (Sweden)

    Geoffrey Dierckxsens

    2016-01-01

    Full Text Available In this article I will examine Ricœur’s idea of the universal in his understanding of justice. Scholars recently discussed the extent to which Ricœur understands universal moral norms and universal rules of justice in his anthropology of human action (e.g., J. Michel, Paul Ricœur: une philosophie de l’agir humain, Paris: Les Éditions du Cerf, 2006, and argue that Ricœur stresses too much the idea of universal moral norms with regard to cultural and moral diversity (e.g., G. H. Taylor, “Ricoeur versus Ricoeur? Between the Universal and the Contextual,” From Ricoeur to Action. The Socio-Political Significance of Ricoeur’s Thinking, Todd S. Mei and David Lewin (eds., (London and New York: Bloomsbury, 2012. G. H. Taylor, “Reenvisioning Justice,” Lo Squarda 12 (2013: 65-80. In this article I will take part in the debate about universalism and approach Ricœur’s idea of the universal from a different angle, in placing it in light of his idea of evil. The point I will aim to make in this article is that Ricœur’s idea of the relation between justice and evil demonstrates what I understand as the ambiguity of justice, which highlights the difficulty of defining universal rules of justice. I will argue that this ambiguity is the following: justice aims at the establishment of social peace and in that sense it is the necessary remedy against human evil, but justice also implies power, and possibly violence, over others in that it relates to violent feelings of vengeance, to institutional mechanism of authority, and to a struggle of values. Yet if rules of justice relate to evil in the sense of power over others, so I argue, then it is problematic to define absolute criteria for rules of justice, i.e., for rules for social peace: because justice relates to particular values, which means that the risk of violence is inherent to institutional rules of justice, there is no ultimate universal set of such rules. This article therefore

  17. A motion-based integer ambiguity resolution method for attitude determination using the global positioning system (GPS)

    International Nuclear Information System (INIS)

    Wang, Bo; Deng, Zhihong; Wang, Shunting; Fu, Mengyin

    2010-01-01

    Loss of the satellite signal and noise disturbance will cause cycle slips to occur in the carrier phase observation of the attitude determination system using the global positioning system (GPS), especially in the dynamic situation. Therefore, in order to reject the error by cycle slips, the integer ambiguity should be re-computed. A motion model-based Kalman predictor is used for the ambiguity re-computation in dynamic applications. This method utilizes the correct observation of the last step to predict the current ambiguities. With the baseline length as a constraint to reject invalid values, we can solve the current integer ambiguity and the attitude angles, by substituting the obtained ambiguities into the constrained LAMBDA method. Experimental results demonstrate that the proposed method is more efficient in the dynamic situation, which takes less time to obtain new fixed ambiguities with a higher mean success rate

  18. Novel ambiguities in the Seiberg-Witten map and the emergent gravity

    International Nuclear Information System (INIS)

    Muthukumar, B.

    2015-01-01

    A homogeneous part of the Seiberg-Witten gauge equivalence relation for gauge fields can lead to solutions that involve matter fields in such a way that the gauge equivalence and the dimensional and index structures are preserved. In particular, we consider scalar fields coupled to U(1) gauge fields. The matter fields appear non-linearly in the map. As an application, we analyze the implication of this ambiguity to emergent gravity at the first order in noncommutative parameter and show that the new ambiguity restores the possibility of conformal coupling of real scalar density field that is coupled non-minimally to the emergent gravity induced by gauge fields — a possibility that is strictly not allowed if we consider only the already known ambiguity in the Seiberg-Witten map.

  19. Ambiguous diagnosis, futile treatments and temporary recovery ...

    African Journals Online (AJOL)

    Ambiguous diagnosis, futile treatments and temporary recovery: Meanings of medical treatment among HIV/AIDS family caregivers providing care without ARVs. ... to understand unstable treatment outcomes; and policy makers should strengthen home-based care by developing policies that integrate palliative care into HIV ...

  20. On the Impact of L2 Speech Rhythm on Syntactic Ambiguity Resolution

    Science.gov (United States)

    Roncaglia-Denissen, M. Paula; Schmidt-Kassow, Maren; Heine, Angela; Kotz, Sonja A.

    2015-01-01

    In an event-related potential (ERP) study we investigated the role of age of acquisition (AoA) on the use of second language rhythmic properties during syntactic ambiguity resolution. Syntactically ambiguous sentences embedded in rhythmically regular and irregular contexts were presented to Turkish early and late second language (L2) learners of…

  1. The Ethics of Ambiguity: Rethinking the Role and Importance of Uncertainty in Medical Education and Practice.

    Science.gov (United States)

    Domen, Ronald E

    2016-01-01

    Understanding and embracing uncertainty are critical for effective teacher-learner relationships as well as for shared decision-making in the physician-patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity.

  2. The interaction of patient race, provider bias, and clinical ambiguity on pain management decisions.

    Science.gov (United States)

    Hirsh, Adam T; Hollingshead, Nicole A; Ashburn-Nardo, Leslie; Kroenke, Kurt

    2015-06-01

    Although racial disparities in pain care are widely reported, much remains to be known about the role of provider and contextual factors. We used computer-simulated patients to examine the influence of patient race, provider racial bias, and clinical ambiguity on pain decisions. One hundred twenty-nine medical residents/fellows made assessment (pain intensity) and treatment (opioid and nonopioid analgesics) decisions for 12 virtual patients with acute pain. Race (black/white) and clinical ambiguity (high/low) were manipulated across vignettes. Participants completed the Implicit Association Test and feeling thermometers, which assess implicit and explicit racial biases, respectively. Individual- and group-level analyses indicated that race and ambiguity had an interactive effect on providers' decisions, such that decisions varied as a function of ambiguity for white but not for black patients. Individual differences across providers were observed for the effect of race and ambiguity on decisions; however, providers' implicit and explicit biases did not account for this variability. These data highlight the complexity of racial disparities and suggest that differences in care between white and black patients are, in part, attributable to the nature (ie, ambiguity) of the clinical scenario. The current study suggests that interventions to reduce disparities should differentially target patient, provider, and contextual factors. This study examined the unique and collective influence of patient race, provider racial bias, and clinical ambiguity on providers' pain management decisions. These results could inform the development of interventions aimed at reducing disparities and improving pain care. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  3. Absence of the Gribov ambiguity in a special algebraic gauge

    Directory of Open Access Journals (Sweden)

    Raval Haresh

    2016-01-01

    Full Text Available The Gribov ambiguity exists in various gauges except algebraic gauges. However in general, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We show that nontrivial copies can not occur in this gauge. We then provide an example of spherically symmetric gauge field configuration and prove that with a proper boundary condition on the configuration, this gauge removes the ambiguity on a compact manifold S3${{\\mathbb S}^3}$.

  4. Ambiguity and risk measures in the lab and students’ real-life borrowing behavior

    NARCIS (Netherlands)

    Fairley, Kim; Weitzel, Utz

    This study analyzes the external validity of experimentally elicited ambiguity aversion, likelihood insensitivity and risk aversion on real-life decision-making in the field of student loans. Our main finding is that ambiguity aversion, likelihood insensitivity and risk aversion are not related to

  5. An ambiguous relationship

    DEFF Research Database (Denmark)

    Søndergaard Larsen, Lene; Hedegaard Larsen, Birte; Birkelund, Regner

    was sometimes depressing and troublesome. Really understanding and caring for fellow patients was painful. Conclusion: The patients’ interaction is characterized as ambiguous, because interaction between the patients holds both resources and strains. The patient as a care provider may cause curiosity among......Background: The significance of social interaction is commonly discussed and intensively studied as a substantial concept in the nursing profession. Social research conducted in hospital settings has prioritised to examine interaction between patients and doctors, patients and nurses and patients....... Too much information from fellow patients might rock patients’ confidence and hope for own recovery 3) a care provider; the patients’ community was characterized by compassion where they either received care from, or provided care to a fellow patient. Interacting with and supporting fellow patients...

  6. Micro-Doppler Ambiguity Resolution for Wideband Terahertz Radar Using Intra-Pulse Interference.

    Science.gov (United States)

    Yang, Qi; Qin, Yuliang; Deng, Bin; Wang, Hongqiang; You, Peng

    2017-04-29

    Micro-Doppler, induced by micro-motion of targets, is an important characteristic of target recognition once extracted via parameter estimation methods. However, micro-Doppler is usually too significant to result in ambiguity in the terahertz band because of its relatively high carrier frequency. Thus, a micro-Doppler ambiguity resolution method for wideband terahertz radar using intra-pulse interference is proposed in this paper. The micro-Doppler can be reduced several dozen times its true value to avoid ambiguity through intra-pulse interference processing. The effectiveness of this method is proved by experiments based on a 0.22 THz wideband radar system, and its high estimation precision and excellent noise immunity are verified by Monte Carlo simulation.

  7. Robustness of climate metrics under climate policy ambiguity

    International Nuclear Information System (INIS)

    Ekholm, Tommi; Lindroos, Tomi J.; Savolainen, Ilkka

    2013-01-01

    Highlights: • We assess the economic impacts of using different climate metrics. • The setting is cost-efficient scenarios for three interpretations of the 2C target. • With each target setting, the optimal metric is different. • Therefore policy ambiguity prevents the selection of an optimal metric. • Robust metric values that perform well with multiple policy targets however exist. -- Abstract: A wide array of alternatives has been proposed as the common metrics with which to compare the climate impacts of different emission types. Different physical and economic metrics and their parameterizations give diverse weights between e.g. CH 4 and CO 2 , and fixing the metric from one perspective makes it sub-optimal from another. As the aims of global climate policy involve some degree of ambiguity, it is not possible to determine a metric that would be optimal and consistent with all policy aims. This paper evaluates the cost implications of using predetermined metrics in cost-efficient mitigation scenarios. Three formulations of the 2 °C target, including both deterministic and stochastic approaches, shared a wide range of metric values for CH 4 with which the mitigation costs are only slightly above the cost-optimal levels. Therefore, although ambiguity in current policy might prevent us from selecting an optimal metric, it can be possible to select robust metric values that perform well with multiple policy targets

  8. Impact of Decorrelation on Search Efficiency of Ambiguity Resolution

    Directory of Open Access Journals (Sweden)

    LU Liguo

    2015-05-01

    Full Text Available The decorrelation performance of LAMBDA algorithm, LLL algorithm and Seysen algorithm are analyzed with evaluation indexes, i.e., condition number, orthogonal defect and S(A. Moreover, relationships between decorrelation performance of the above algorithms and ambiguity search efficiency are evaluated using theoretical and practical validation, respectively. The results validate that there is no inevitable relation between decorrelation performance of variance-covariance matrix of original ambiguity and search efficiency, whereas, traditional views consider that search efficiency can be enhanced just by improving decorrelation performance. Further analysis shows that the essence to improving search efficiency major depends on the permutation of basis vectors according to a certain direction.

  9. Making Decisions under Ambiguity: Judgment Bias Tasks for Assessing Emotional State in Animals

    Science.gov (United States)

    Roelofs, Sanne; Boleij, Hetty; Nordquist, Rebecca E.; van der Staay, Franz Josef

    2016-01-01

    Judgment bias tasks (JBTs) are considered as a family of promising tools in the assessment of emotional states of animals. JBTs provide a cognitive measure of optimism and/or pessimism by recording behavioral responses to ambiguous stimuli. For instance, a negative emotional state is expected to produce a negative or pessimistic judgment of an ambiguous stimulus, whereas a positive emotional state produces a positive or optimistic judgment of the same ambiguous stimulus. Measuring an animal’s emotional state or mood is relevant in both animal welfare research and biomedical research. This is reflected in the increasing use of JBTs in both research areas. We discuss the different implementations of JBTs with animals, with a focus on their potential as an accurate measure of emotional state. JBTs have been successfully applied to a very broad range of species, using many different types of testing equipment and experimental protocols. However, further validation of this test is deemed necessary. For example, the often extensive training period required for successful judgment bias testing remains a possible factor confounding results. Also, the issue of ambiguous stimuli losing their ambiguity with repeated testing requires additional attention. Possible improvements are suggested to further develop the JBTs in both animal welfare and biomedical research. PMID:27375454

  10. Emotion and decision-making under uncertainty: Physiological arousal predicts increased gambling during ambiguity but not risk.

    Science.gov (United States)

    FeldmanHall, Oriel; Glimcher, Paul; Baker, Augustus L; Phelps, Elizabeth A

    2016-10-01

    Uncertainty, which is ubiquitous in decision-making, can be fractionated into known probabilities (risk) and unknown probabilities (ambiguity). Although research has illustrated that individuals more often avoid decisions associated with ambiguity compared to risk, it remains unclear why ambiguity is perceived as more aversive. Here we examine the role of arousal in shaping the representation of value and subsequent choice under risky and ambiguous decisions. To investigate the relationship between arousal and decisions of uncertainty, we measure skin conductance response-a quantifiable measure reflecting sympathetic nervous system arousal-during choices to gamble under risk and ambiguity. To quantify the discrete influences of risk and ambiguity sensitivity and the subjective value of each option under consideration, we model fluctuating uncertainty, as well as the amount of money that can be gained by taking the gamble. Results reveal that although arousal tracks the subjective value of a lottery regardless of uncertainty type, arousal differentially contributes to the computation of value-that is, choice-depending on whether the uncertainty is risky or ambiguous: Enhanced arousal adaptively decreases risk-taking only when the lottery is highly risky but increases risk-taking when the probability of winning is ambiguous (even after controlling for subjective value). Together, this suggests that the role of arousal during decisions of uncertainty is modulatory and highly dependent on the context in which the decision is framed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  11. In Command And Out Of Control: Leaders Developing Teams That Thrive In Chaos And Ambiguity

    Science.gov (United States)

    2016-05-26

    In Command and Out of Control: Leaders Developing Teams that Thrive in Chaos and Ambiguity A Monograph by...TITLE AND SUBTITLE Sa. CONTRACT NUMBER In Command and Out of Control: Leaders Developing Teams that Thrive in Chaos and Ambiguity Sb. GRANT NUMBER...the chaos and ambiguity associated with war. Teams must provide the innovative and creative solutions formerly left to the individual leader. This

  12. Exploring Situated Ambiguity in Students' Entrepreneurial Learning

    Science.gov (United States)

    Kubberød, Elin; Pettersen, Inger Beate

    2017-01-01

    Purpose: Building on entrepreneurial learning research, the purpose of this paper is to argue that the students participating in foreign entrepreneurial education programmes can have realistic entrepreneurial learning experiences. This research addresses two specific questions: how situated ambiguity induced by a foreign culture may contribute to…

  13. Hippocampal Processing of Ambiguity Enhances Fear Memory.

    Science.gov (United States)

    Amadi, Ugwechi; Lim, Seh Hong; Liu, Elizabeth; Baratta, Michael V; Goosens, Ki A

    2017-02-01

    Despite the ubiquitous use of Pavlovian fear conditioning as a model for fear learning, the highly predictable conditions used in the laboratory do not resemble real-world conditions, in which dangerous situations can lead to unpleasant outcomes in unpredictable ways. In the current experiments, we varied the timing of aversive events after predictive cues in rodents and discovered that temporal ambiguity of aversive events greatly enhances fear. During fear conditioning with unpredictably timed aversive events, pharmacological inactivation of the dorsal hippocampus or optogenetic silencing of cornu ammonis 1 cells during aversive negative prediction errors prevented this enhancement of fear without affecting fear learning for predictable events. Dorsal hippocampal inactivation also prevented ambiguity-related enhancement of fear during auditory fear conditioning under a partial-reinforcement schedule. These results reveal that information about the timing and occurrence of aversive events is rapidly acquired and that unexpectedly timed or omitted aversive events generate hippocampal signals to enhance fear learning.

  14. Learning, Teaching and Ambiguity in Virtual Worlds

    Science.gov (United States)

    Carr, Diane; Oliver, Martin; Burn, Andrew

    What might online communities and informal learning practices teach us about virtual world pedagogy? In this chapter we describe a research project in which learning practices in online worlds such as World of Warcraft and Second LifeTM (SL) were investigated. Working within an action research framework, we employed a range of methods to investigate how members of online communities define the worlds they encounter, negotiate the terms of participation, and manage the incremental complexity of game worlds. The implications of such practices for online pedagogy were then explored through teaching in SL. SL eludes simple definitions. Users, or "residents", of SL partake of a range of pleasures and activities - socialising, building, creating and exhibiting art, playing games, exploring, shopping, or running a business, for instance. We argue that the variable nature of SL gives rise to degrees of ambiguity. This ambiguity impacts on inworld social practices, and has significant implications for online teaching and learning.

  15. Obstetricians' choice of cesarean delivery in ambiguous cases

    DEFF Research Database (Denmark)

    Fuglenes, Dorthe; Oian, Pål; Kristiansen, Ivar Sønbø

    2009-01-01

    OBJECTIVE: The aim of this study was to test the hypothesis that obstetricians' choice of delivery method is influenced by their risk attitude and perceived risk of complaints and malpractice litigation. STUDY DESIGN: The choice of delivery method in ambiguous cases was studied in a nationwide...... survey of Norwegian obstetricians (n = 716; response rate, 71%) using clinical scenarios. The risk attitude was measured by 6 items from the Jackson Personality Inventory-Revised. RESULTS: The proportion of obstetricians consenting to the cesarean request varied both within and across the scenarios....... The perceived risk of complaints and malpractice litigation was a clear determinant of obstetricians' choice of cesarean in all of the clinical scenarios, whereas no impact was observed for risk attitude. CONCLUSION: Obstetricians' judgments about cesarean request in ambiguous clinical cases vary considerably...

  16. Mentoring relationships and the levels of role conflict and role ambiguity experienced by novice nursing faculty.

    Science.gov (United States)

    Specht, Jennifer A

    2013-01-01

    This study explored the effect of mentoring on the levels of role conflict and role ambiguity experienced by novice nursing faculty related to their transitions into academe using a descriptive, comparative design. It also measured the relationship between the quality of mentoring experiences of novice nursing faculty and their levels of role conflict and role ambiguity using a correlational design. P. Benner's (1984) novice to expert model was utilized as a framework for successful role transition. J. R. Rizzo, R. J. House, and S. I. Lirtzman's (1970) role conflict and role ambiguity scale was used to measure the levels of role conflict and role ambiguity experienced by novice nursing faculty. Results indicate that participants (n = 224) who were mentored have significantly lower levels of role conflict (M = 3.57) and role ambiguity (M = 3.02) than those who were not mentored (M = 4.62 and M = 3.90, respectively). Also significant, the higher the participants' reported levels of quality of mentoring experiences were, the lower their levels of role conflict and role ambiguity were. The results of this study indicate that mentoring eases the transition of novice nursing faculty from practice into academe by decreasing the degree of role ambiguity and role conflict that they experience. © 2013.

  17. Medical Student and Junior Doctors' Tolerance of Ambiguity: Development of a New Scale

    Science.gov (United States)

    Hancock, Jason; Roberts, Martin; Monrouxe, Lynn; Mattick, Karen

    2015-01-01

    The practice of medicine involves inherent ambiguity, arising from limitations of knowledge, diagnostic problems, complexities of treatment and outcome and unpredictability of patient response. Research into doctors' tolerance of ambiguity is hampered by poor conceptual clarity and inadequate measurement scales. We aimed to create and pilot a…

  18. The tell-tale heart: physiological reactivity during resolution of ambiguity in youth anxiety.

    Science.gov (United States)

    Rozenman, Michelle; Vreeland, Allison; Iglesias, Marisela; Mendez, Melissa; Piacentini, John

    2018-03-01

    In the past decade, cognitive biases and physiological arousal have each been proposed as mechanisms through which paediatric anxiety develops and is maintained over time. Preliminary studies have found associations between anxious interpretations of ambiguity, physiological arousal, and avoidance, supporting theories that link cognition, psychophysiology, and behaviour. However, little is known about the relationship between youths' resolutions of ambiguity and physiological arousal during acute stress. Such information may have important clinical implications for use of verbal self-regulation strategies and cognitive restructuring during treatments for paediatric anxiety. In this brief report, we present findings suggesting that anxious, but not typically developing, youth select avoidant goals via non-threatening resolution of ambiguity during a stressor, and that this resolution of ambiguity is accompanied by physiological reactivity (heart rate, heart rate variability, and respiratory sinus arrhythmia). We propose future empirical research on the interplay between interpretation bias, psychophysiology, and child anxiety, as well as clinical implications.

  19. Resolving the sign ambiguity in ΔΓs with Bs→DsK

    International Nuclear Information System (INIS)

    Nandi, Soumitra; Nierste, Ulrich

    2008-01-01

    The analysis of tagged B s →J/ψφ decays determines the CP phase φ s in B s -B s mixing with a twofold ambiguity. The solutions differ in the sign of cosφ s which equals the sign of the width difference ΔΓ s among the two B s mass eigenstates. We point out that this ambiguity can be removed with the help of B s →D s K decays. We compare untagged and tagged strategies and find the tagged analysis more promising. The removal of the sign ambiguity in ΔΓ s can be done with relatively low statistics and could therefore be a target for the early stage of B s →D s K studies.

  20. Ambiguity Of Doppler Centroid In Synthetic-Aperture Radar

    Science.gov (United States)

    Chang, Chi-Yung; Curlander, John C.

    1991-01-01

    Paper discusses performances of two algorithms for resolution of ambiguity in estimated Doppler centroid frequency of echoes in synthetic-aperture radar. One based on range-cross-correlation technique, other based on multiple-pulse-repetition-frequency technique.

  1. Instantaneous and controllable integer ambiguity resolution: review and an alternative approach

    Science.gov (United States)

    Zhang, Jingyu; Wu, Meiping; Li, Tao; Zhang, Kaidong

    2015-11-01

    In the high-precision application of Global Navigation Satellite System (GNSS), integer ambiguity resolution is the key step to realize precise positioning and attitude determination. As the necessary part of quality control, integer aperture (IA) ambiguity resolution provides the theoretical and practical foundation for ambiguity validation. It is mainly realized by acceptance testing. Due to the constraint of correlation between ambiguities, it is impossible to realize the controlling of failure rate according to analytical formula. Hence, the fixed failure rate approach is implemented by Monte Carlo sampling. However, due to the characteristics of Monte Carlo sampling and look-up table, we have to face the problem of a large amount of time consumption if sufficient GNSS scenarios are included in the creation of look-up table. This restricts the fixed failure rate approach to be a post process approach if a look-up table is not available. Furthermore, if not enough GNSS scenarios are considered, the table may only be valid for a specific scenario or application. Besides this, the method of creating look-up table or look-up function still needs to be designed for each specific acceptance test. To overcome these problems in determination of critical values, this contribution will propose an instantaneous and CONtrollable (iCON) IA ambiguity resolution approach for the first time. The iCON approach has the following advantages: (a) critical value of acceptance test is independently determined based on the required failure rate and GNSS model without resorting to external information such as look-up table; (b) it can be realized instantaneously for most of IA estimators which have analytical probability formulas. The stronger GNSS model, the less time consumption; (c) it provides a new viewpoint to improve the research about IA estimation. To verify these conclusions, multi-frequency and multi-GNSS simulation experiments are implemented. Those results show that IA

  2. The input ambiguity hypothesis and case blindness: an account of cross-linguistic and intra-linguistic differences in case errors.

    Science.gov (United States)

    Pelham, Sabra D

    2011-03-01

    English-acquiring children frequently make pronoun case errors, while German-acquiring children rarely do. Nonetheless, German-acquiring children frequently make article case errors. It is proposed that when child-directed speech contains a high percentage of case-ambiguous forms, case errors are common in child language; when percentages are low, case errors are rare. Input to English and German children was analyzed for percentage of case-ambiguous personal pronouns on adult tiers of corpora from 24 English-acquiring and 24 German-acquiring children. Also analyzed for German was the percentage of case-ambiguous articles. Case-ambiguous pronouns averaged 63·3% in English, compared with 7·6% in German. The percentage of case-ambiguous articles in German was 77·0%. These percentages align with the children's errors reported in the literature. It appears children may be sensitive to levels of ambiguity such that low ambiguity may aid error-free acquisition, while high ambiguity may blind children to case distinctions, resulting in errors.

  3. An ambiguous relationship

    DEFF Research Database (Denmark)

    Søndergaard Larsen, Lene; Hedegaard Larsen, Birte; Birkelund, Regner

    2013-01-01

    to qualitative data analysis. Results:  The qualitative meta-synthesis resulted in the heading An Ambiguous Relationship under which three core categories illustrate the hospitalized patients’ different interaction roles. The core categories were as follows: (i) the fellow patient experienced as an enforced......Aim:  The aim of this study was to provide a clear view of the existing knowledge regarding patients’ significance to fellow patients during hospitalization. Method:  Sandelowski and Barroso’s approach to qualitative meta-synthesis was selected and systematically used for collecting and assessing...... findings from qualitative studies. Data consisted of seven qualitative studies published as one book, four scientific articles and two doctoral theses from Scotland, UK, Norway and Denmark. The analysis and synthesis were conducted with inspiration from both Sandelowski and Barroso and Ian Dey’s approach...

  4. Searching for the best model: ambiguity of inverse solutions and application to fetal magnetoencephalography

    International Nuclear Information System (INIS)

    Vrba, J; Robinson, S E; McCubbin, J; Lowery, C L; Eswaran, H; Murphy, P; Preissl, H

    2007-01-01

    Fetal brain signals produce weak magnetic fields at the maternal abdominal surface. In the presence of much stronger interference these weak fetal fields are often nearly indistinguishable from noise. Our initial objective was to validate these weak fetal brain fields by demonstrating that they agree with the electromagnetic model of the fetal brain. The fetal brain model is often not known and we have attempted to fit the data to not only the brain source position, orientation and magnitude, but also to the brain model position. Simulation tests of this extended model search on fetal MEG recordings using dipole fit and beamformers revealed a region of ambiguity. The region of ambiguity consists of a family of models which are not distinguishable in the presence of noise, and which exhibit large and comparable SNR when beamformers are used. Unlike the uncertainty of a dipole fit with known model plus noise, this extended ambiguity region yields nearly identical forward solutions, and is only weakly dependent on noise. The ambiguity region is located in a plane defined by the source position, orientation, and the true model centre, and will have a diameter approximately 0.67 of the modelled fetal head diameter. Existence of the ambiguity region allows us to only state that the fetal brain fields do not contradict the electromagnetic model; we can associate them with a family of models belonging to the ambiguity region, but not with any specific model. In addition to providing a level of confidence in the fetal brain signals, the ambiguity region knowledge in combination with beamformers allows detection of undistorted temporal waveforms with improved signal-to-noise ratio, even though the source position cannot be uniquely determined

  5. Sealed bid auctions with ambiguity: an experimental study

    Czech Academy of Sciences Publication Activity Database

    Chen, Y.; Katuščák, Peter; Ozdenoren, E.

    -, č. 269 (2005), s. 1-75 ISSN 1211-3298 Institutional research plan: CEZ:AV0Z70850503 Keywords : sealed bid auctions * ambiguity * experiment Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp269.pdf

  6. Is ambiguity tolerance malleable? Experimental evidence with potential implications for future research

    Directory of Open Access Journals (Sweden)

    Megan L Endres

    2015-05-01

    Full Text Available We conducted two research studies to address the malleability of TA by manipulating situational ambiguity. Students participated in a semester-end assessment of their management skills (n = 306. In Study 1, students in low and moderate ambiguity conditions had significantly higher post-experiment TA, more positive change in self-efficacy, and marginally higher faculty ratings. In Study 2, a control group (n = 103 did not participate in the assessment and was established for comparison to the first study results. The Study 2 students reported TA significantly lower than Study 1 students in the low and moderate ambiguity conditions. The control group TA was not significantly different from that of the Study 1 high ambiguity condition. This further suggested TA’s situational malleability, as those who had controlled access to structured information appeared to have increased their TA over that observed in the other two groups. These results suggest that TA may be malleable. We review the relevant literature, offer hypotheses, report our analyses and findings, and then propose future research and potential prescriptive applications in such areas as management development, assessment, and decision-making.

  7. An integer ambiguity resolution method for the global positioning system (GPS)-based land vehicle attitude determination

    International Nuclear Information System (INIS)

    Wang, Bo; Miao, Lingjuan; Wang, Shunting; Shen, Jun

    2009-01-01

    During attitude determination using a global positioning system (GPS), cycle slips occur due to the loss of lock and noise disturbance. Therefore, the integer ambiguity needs re-computation to isolate the error in carrier phase. This paper presents a fast method for integer ambiguity resolution for land vehicle application. After the cycle slips are detected, the velocity vector is utilized to obtain the rough baseline vector. The obtained baseline vector is substituted into carrier phase observation equations to solve the float ambiguity solution which can be used as a constraint to accelerate the integer ambiguity search procedure at next epochs. The probability of correct integer estimation in the expanded search space is analyzed. Experimental results demonstrate that the proposed method gives a fast approach to obtain new fixed ambiguities while the regular method takes longer time and sometimes results in incorrect solutions

  8. Sensitivity to Referential Ambiguity in Discourse: The Role of Attention, Working Memory, and Verbal Ability.

    Science.gov (United States)

    Boudewyn, Megan A; Long, Debra L; Traxler, Matthew J; Lesh, Tyler A; Dave, Shruti; Mangun, George R; Carter, Cameron S; Swaab, Tamara Y

    2015-12-01

    The establishment of reference is essential to language comprehension. The goal of this study was to examine listeners' sensitivity to referential ambiguity as a function of individual variation in attention, working memory capacity, and verbal ability. Participants listened to stories in which two entities were introduced that were either very similar (e.g., two oaks) or less similar (e.g., one oak and one elm). The manipulation rendered an anaphor in a subsequent sentence (e.g., oak) ambiguous or unambiguous. EEG was recorded as listeners comprehended the story, after which participants completed tasks to assess working memory, verbal ability, and the ability to use context in task performance. Power in the alpha and theta frequency bands when listeners received critical information about the discourse entities (e.g., oaks) was used to index attention and the involvement of the working memory system in processing the entities. These measures were then used to predict an ERP component that is sensitive to referential ambiguity, the Nref, which was recorded when listeners received the anaphor. Nref amplitude at the anaphor was predicted by alpha power during the earlier critical sentence: Individuals with increased alpha power in ambiguous compared with unambiguous stories were less sensitive to the anaphor's ambiguity. Verbal ability was also predictive of greater sensitivity to referential ambiguity. Finally, increased theta power in the ambiguous compared with unambiguous condition was associated with higher working-memory span. These results highlight the role of attention and working memory in referential processing during listening comprehension.

  9. Role Conflict and Ambiguity as Predictors of Job Satisfaction in High School Counselors

    Science.gov (United States)

    Cervoni, Annemarie; DeLucia-Waack, Janice

    2011-01-01

    The purpose of this study was to examine the relationship between role conflict and role ambiguity, and percentage of time spent on ASCA recommended duties (counseling, coordination, consultation, and large group guidance); and job satisfaction of high school counselors. The Role Conflict and Role Ambiguity Scale and the Job Descriptive Index were…

  10. The ambiguous challenge of intranets

    DEFF Research Database (Denmark)

    Thommesen, Jacob

    2003-01-01

    increases with tendencies to cooperate and communicate across organisational boundaries, mainly as a reaction to developments in markets and industrial knowledge base, but also due to the potential provided by computer network. In the third chapter I identify some characteristics of two fundamental intranet...... media, email and the web, partly in the perspective of media richness theory, partly compared with philosophical discussions of classical media. The fourth chapter presents an intranet in a global company, in which problems and challenges related to ambiguity have proven significant....

  11. From expert generalists to ambiguity masters: using ambiguity tolerance theory to redefine the practice of rural nurses.

    Science.gov (United States)

    Knight, Kaye; Kenny, Amanda; Endacott, Ruth

    2016-06-01

    To redefine the practice of rural nurses and describe a model that conceptualises the capabilities and characteristics required in the rural environment. The way in which the practice of rural nurses has been conceptualised is problematic. Definitions of rural nursing have been identified primarily through the functional context of rural health service delivery. The expert generalist term has provided a foundation theory for rural nurses with understandings informed by the scope of practice needed to meet service delivery requirements. However, authors exploring intrinsic characteristics of rural nurses have challenged this definition, as it does not adequately address the deeper, intangible complexities of practice required in the rural context. Despite this discourse, an alternative way to articulate the distinctive nature of rural nursing practice has eluded authors in Australia and internationally. A theoretical paper based on primary research. The development of the model was informed by the findings of a study that explored the nursing practice of managing telephone presentations in rural health services in Victoria, Australia. The study involved policy review from State and Federal governments, nursing and medical professional bodies, and five rural health services; semi-structured interviews with eight Directors of Nursing, seven registered nurses and focus group interviews with eight registered nurses. An ambiguity tolerance model drawn from corporate global entrepreneurship theory was adapted to explain the findings of the study. The adapted model presents capabilities and characteristics used by nurses to successfully manage the ambiguity of providing care in the rural context. Redefining the practice of rural nurses, through an adapted theory of ambiguity tolerance, highlights nursing characteristics and capabilities required in the rural context. This perspective offers new ways of thinking about the work of rural nurses, rural nurse policy, education

  12. Beyond RGB: Very high resolution urban remote sensing with multimodal deep networks

    Science.gov (United States)

    Audebert, Nicolas; Le Saux, Bertrand; Lefèvre, Sébastien

    2018-06-01

    In this work, we investigate various methods to deal with semantic labeling of very high resolution multi-modal remote sensing data. Especially, we study how deep fully convolutional networks can be adapted to deal with multi-modal and multi-scale remote sensing data for semantic labeling. Our contributions are threefold: (a) we present an efficient multi-scale approach to leverage both a large spatial context and the high resolution data, (b) we investigate early and late fusion of Lidar and multispectral data, (c) we validate our methods on two public datasets with state-of-the-art results. Our results indicate that late fusion make it possible to recover errors steaming from ambiguous data, while early fusion allows for better joint-feature learning but at the cost of higher sensitivity to missing data.

  13. Evidence for a differential interference of noise in sub-lexical and lexical reading routes in healthy participants and dyslexics.

    Science.gov (United States)

    Pina Rodrigues, Ana; Rebola, José; Jorge, Helena; Ribeiro, Maria José; Pereira, Marcelino; Castelo-Branco, Miguel; van Asselen, Marieke

    The ineffective exclusion of surrounding noise has been proposed to underlie the reading deficits in developmental dyslexia. However, previous studies supporting this hypothesis focused on low-level visual tasks, providing only an indirect link of noise interference on reading processes. In this study, we investigated the effect of noise on regular, irregular, and pseudoword reading in 23 dyslexic children and 26 age- and IQ-matched controls, by applying the white noise displays typically used to validate this theory to a lexical decision task. Reading performance and eye movements were measured. Results showed that white noise did not consistently affect dyslexic readers more than typical readers. Noise affected more dyslexic than typical readers in terms of reading accuracy, but it affected more typical than dyslexic readers in terms of response time and eye movements (number of fixations and regressions). Furthermore, in typical readers, noise affected more the speed of reading of pseudowords than real words. These results suggest a particular impact of noise on the sub-lexical reading route where attention has to be deployed to individual letters. The use of a lexical route would reduce the effect of noise. A differential impact of noise between words and pseudowords may therefore not be evident in dyslexic children if they are not yet proficient in using the lexical route. These findings indicate that the type of reading stimuli and consequent reading strategies play an important role in determining the effects of noise interference in reading processing and should be taken into account by further studies.

  14. Effect of Changing Governance System: Result of Western Style Management Adoption to Japanese Culture of Ambiguity

    Directory of Open Access Journals (Sweden)

    Kohichiro Hotta

    2009-02-01

    Full Text Available This paper considers the difficulty of management style change through observation of the management style of Company-A, one of the biggest Japanese IT companies. Japanese economy grew after World War II until the early 1990's. During that era, Ba or SECI process worked in Japanese organizations very well. Further, there was an ambiguous culture in the background of such characteristics. Some kinds of ambiguity or adhocracy made positive effects for Japanese organizational activity, or ambiguity played an important role for Ba activity. There were nested Ba's in each organization with ambiguity. Ambiguous descriptions of roles for each organizational unit activated nested Ba's and generated hot groups. After the economic crisis, Company-A changed its governance and gave clear targets for each organizational unit and for each employee. This change gave new difficulty and diminishes its competence. The change denied the ambiguity in the organization but it was the basis of the competence. Adopting a new system of governance is not a simple activity. Systems must be adjusted to the culture of the organization. Company-A should study competitors in different cultures and adjust the methodology for its culture.

  15. Interpretative bias in spider phobia: Perception and information processing of ambiguous schematic stimuli.

    Science.gov (United States)

    Haberkamp, Anke; Schmidt, Filipp

    2015-09-01

    This study investigates the interpretative bias in spider phobia with respect to rapid visuomotor processing. We compared perception, evaluation, and visuomotor processing of ambiguous schematic stimuli between spider-fearful and control participants. Stimuli were produced by gradually morphing schematic flowers into spiders. Participants rated these stimuli related to their perceptual appearance and to their feelings of valence, disgust, and arousal. Also, they responded to the same stimuli within a response priming paradigm that measures rapid motor activation. Spider-fearful individuals showed an interpretative bias (i.e., ambiguous stimuli were perceived as more similar to spiders) and rated spider-like stimuli as more unpleasant, disgusting, and arousing. However, we observed no differences between spider-fearful and control participants in priming effects for ambiguous stimuli. For non-ambiguous stimuli, we observed a similar enhancement for phobic pictures as has been reported previously for natural images. We discuss our findings with respect to the visual representation of morphed stimuli and to perceptual learning processes. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Flexible taxonomic assignment of ambiguous sequencing reads

    Directory of Open Access Journals (Sweden)

    Jansson Jesper

    2011-01-01

    Full Text Available Abstract Background To characterize the diversity of bacterial populations in metagenomic studies, sequencing reads need to be accurately assigned to taxonomic units in a given reference taxonomy. Reads that cannot be reliably assigned to a unique leaf in the taxonomy (ambiguous reads are typically assigned to the lowest common ancestor of the set of species that match it. This introduces a potentially severe error in the estimation of bacteria present in the sample due to false positives, since all species in the subtree rooted at the ancestor are implicitly assigned to the read even though many of them may not match it. Results We present a method that maps each read to a node in the taxonomy that minimizes a penalty score while balancing the relevance of precision and recall in the assignment through a parameter q. This mapping can be obtained in time linear in the number of matching sequences, because LCA queries to the reference taxonomy take constant time. When applied to six different metagenomic datasets, our algorithm produces different taxonomic distributions depending on whether coverage or precision is maximized. Including information on the quality of the reads reduces the number of unassigned reads but increases the number of ambiguous reads, stressing the relevance of our method. Finally, two measures of performance are described and results with a set of artificially generated datasets are discussed. Conclusions The assignment strategy of sequencing reads introduced in this paper is a versatile and a quick method to study bacterial communities. The bacterial composition of the analyzed samples can vary significantly depending on how ambiguous reads are assigned depending on the value of the q parameter. Validation of our results in an artificial dataset confirm that a combination of values of q produces the most accurate results.

  17. The Ambiguous Role of Constraints in Creativity

    DEFF Research Database (Denmark)

    Biskjær, Michael Mose; Onarheim, Balder; Wiltschnig, Stefan

    2011-01-01

    The relationship between creativity and constraints is often described in the literature either in rather imprecise, general concepts or in relation to very specific domains. Cross-domain and cross-disciplinary takes on how the handling of constraints influences creative activities are rare. In t......-disciplinary research into the ambiguous role of constraints in creativity....

  18. Dealing with behavioral ambiguity in textual process descriptions

    NARCIS (Netherlands)

    van der Aa, Han; Leopold, Henrik; Reijers, Hajo A.

    2016-01-01

    Textual process descriptions are widely used in organizations since they can be created and understood by virtually everyone. The inherent ambiguity of natural language, however, impedes the automated analysis of textual process descriptions. While human readers can use their context knowledge to

  19. Sealed bid auctions with ambiguity: theory and experiments

    Czech Academy of Sciences Publication Activity Database

    Chen, Y.; Katuščák, Peter; Ozdenoren, E.

    2007-01-01

    Roč. 136, č. 1 (2007), s. 513-535 ISSN 0022-0531 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : sealed bid auctions * ambiguity * experiment Subject RIV: AH - Economics Impact factor: 1.353, year: 2007

  20. Diabetic fetopathy associated with bilateral adrenal hyperplasia and ambiguous genitalia: a case report

    Directory of Open Access Journals (Sweden)

    Tantbirojn Patou

    2008-07-01

    Full Text Available Abstract Introduction Many fetal malformations can occur because of maternal diabetes. However, ambiguous genital organs have never been reported as an associated finding in the literature. This is the first report of associated ambiguous genital organ and bilateral adrenal hyperplasia in a case of diabetic fetopathy. Case presentation A 19-year-old Thai primigravida with familial history of diabetes mellitus (DM was diagnosed as having gestational DM type 2, based on 100 g oral glucose tolerance test, and was poorly controlled with insulin injections. Delayed targeted ultrasonography at 28 weeks gestation revealed multiple fetal anomalies. The woman underwent low transverse cesarean section at 30 weeks gestation due to preterm labor and transverse lie. The newborn with ambiguous genitalia was delivered but expired after birth. Autopsy findings revealed alobar holoprosencephaly, a prominent forehead, hypotelorism, an absent nose, absent bilateral ears, median cleft lip and palate, preaxial polydactyly of the right hand, accessory spleens, single umbilical artery, markedly enlarged adrenal glands and ambiguous external genitalia The subsequent fetal chromosomal study revealed 46,XX. Conclusion We describe a case of diabetic fetopathy with classic facial malformation and preaxial hallucal polydactyly which has been proposed as a marker of diabetic embryopathy. Bilateral adrenal hyperplasia with ambiguous genitalia, an uncommon associated anomaly, was also identified. It is controversial whether adrenal hyperplasia can be a novel feature of diabetic fetopathy or just a coincidental finding. Further observation and adequate investigation are needed in such cases.

  1. Audiovisual Capture with Ambiguous Audiovisual Stimuli

    Directory of Open Access Journals (Sweden)

    Jean-Michel Hupé

    2011-10-01

    Full Text Available Audiovisual capture happens when information across modalities get fused into a coherent percept. Ambiguous multi-modal stimuli have the potential to be powerful tools to observe such effects. We used such stimuli made of temporally synchronized and spatially co-localized visual flashes and auditory tones. The flashes produced bistable apparent motion and the tones produced ambiguous streaming. We measured strong interferences between perceptual decisions in each modality, a case of audiovisual capture. However, does this mean that audiovisual capture occurs before bistable decision? We argue that this is not the case, as the interference had a slow temporal dynamics and was modulated by audiovisual congruence, suggestive of high-level factors such as attention or intention. We propose a framework to integrate bistability and audiovisual capture, which distinguishes between “what” competes and “how” it competes (Hupé et al., 2008. The audiovisual interactions may be the result of contextual influences on neural representations (“what” competes, quite independent from the causal mechanisms of perceptual switches (“how” it competes. This framework predicts that audiovisual capture can bias bistability especially if modalities are congruent (Sato et al., 2007, but that is fundamentally distinct in nature from the bistable competition mechanism.

  2. A few approaches to remove ambiguous factors in x-ray spectrum analysis

    International Nuclear Information System (INIS)

    Sera, K.; Futatsugawa, S.

    1993-01-01

    A few attempts have been done to reduce ambiguous factors in the analysis of complex x-ray spectra. Uncertainty in peak identification and separation due to overlapping of x-ray peaks can be reduced by taking into account the response function of x-ray peaks and by using peak functions including all the x-ray sub-lines in a x-ray series. Ambiguous factors due to discontinuity of backgrounds which is sometimes followed by huge peaks can be reduced by considering contributions from the pile-up, escape and tail functions. The problem of uncertainty in the background fitting in a region of low x-ray energy, where many peaks overlap each other and determination of the background function contains much difficulties and ambiguities, can be solved by using peak functions involving tails in place of Gaussians. (author)

  3. Visual working memory contents bias ambiguous structure from motion perception.

    Directory of Open Access Journals (Sweden)

    Lisa Scocchia

    Full Text Available The way we perceive the visual world depends crucially on the state of the observer. In the present study we show that what we are holding in working memory (WM can bias the way we perceive ambiguous structure from motion stimuli. Holding in memory the percept of an unambiguously rotating sphere influenced the perceived direction of motion of an ambiguously rotating sphere presented shortly thereafter. In particular, we found a systematic difference between congruent dominance periods where the perceived direction of the ambiguous stimulus corresponded to the direction of the unambiguous one and incongruent dominance periods. Congruent dominance periods were more frequent when participants memorized the speed of the unambiguous sphere for delayed discrimination than when they performed an immediate judgment on a change in its speed. The analysis of dominance time-course showed that a sustained tendency to perceive the same direction of motion as the prior stimulus emerged only in the WM condition, whereas in the attention condition perceptual dominance dropped to chance levels at the end of the trial. The results are explained in terms of a direct involvement of early visual areas in the active representation of visual motion in WM.

  4. Constant resolution of time-dependent Hartree--Fock phase ambiguity

    International Nuclear Information System (INIS)

    Lichtner, P.C.; Griffin, J.J.; Schultheis, H.; Schultheis, R.; Volkov, A.B.

    1978-01-01

    The customary time-dependent Hartree--Fock problem is shown to be ambiguous up to an arbitrary function of time additive to H/sub HF/, and, consequently, up to an arbitrary time-dependent phase for the solution, PHI(t). The ''constant'' (H)'' phase is proposed as the best resolution of this ambiguity. It leads to the following attractive features: (a) the time-dependent Hartree--Fock (TDHF) Hamiltonian, H/sub HF/, becomes a quantity whose expectation value is equal to the average energy and, hence, constant in time; (b) eigenstates described exactly by determinants, have time-dependent Hartree--Fock solutions identical with the exact time-dependent solutions; (c) among all possible TDHF solutions this choice minimizes the norm of the quantity (H--i dirac constant delta/delta t) operating on the ket PHI, and guarantees optimal time evolution over an infinitesimal period; (d) this choice corresponds both to the stationary value of the absolute difference between (H) and (i dirac constant delta/delta t) and simultaneously to its absolute minimal value with respect to choice of the time-dependent phase. The source of the ambiguity is discussed. It lies in the time-dependent generalization of the freedom to transform unitarily among the single-particle states of a determinant at the (physically irrelevant for stationary states) cost of altering only a factor of unit magnitude

  5. Compressive Sensing Based Bayesian Sparse Channel Estimation for OFDM Communication Systems: High Performance and Low Complexity

    Science.gov (United States)

    Xu, Li; Shan, Lin; Adachi, Fumiyuki

    2014-01-01

    In orthogonal frequency division modulation (OFDM) communication systems, channel state information (CSI) is required at receiver due to the fact that frequency-selective fading channel leads to disgusting intersymbol interference (ISI) over data transmission. Broadband channel model is often described by very few dominant channel taps and they can be probed by compressive sensing based sparse channel estimation (SCE) methods, for example, orthogonal matching pursuit algorithm, which can take the advantage of sparse structure effectively in the channel as for prior information. However, these developed methods are vulnerable to both noise interference and column coherence of training signal matrix. In other words, the primary objective of these conventional methods is to catch the dominant channel taps without a report of posterior channel uncertainty. To improve the estimation performance, we proposed a compressive sensing based Bayesian sparse channel estimation (BSCE) method which cannot only exploit the channel sparsity but also mitigate the unexpected channel uncertainty without scarifying any computational complexity. The proposed method can reveal potential ambiguity among multiple channel estimators that are ambiguous due to observation noise or correlation interference among columns in the training matrix. Computer simulations show that proposed method can improve the estimation performance when comparing with conventional SCE methods. PMID:24983012

  6. Static vs Dynamic Auctions with Ambiguity Averse Bidders

    NARCIS (Netherlands)

    Carvalho, M.

    2012-01-01

    Abstract: This paper presents the outcome of a dynamic price-descending auction when the distribution of the private values is uncertain and bidders exhibit ambiguity aversion. In contrast to sealed-bid auctions, in open auctions the bidders get information about the other bidders' private values

  7. Resolution of ambiguities in cartoons as an illustration of the role of pragmatics in natural language understanding by computers

    Energy Technology Data Exchange (ETDEWEB)

    Mazlack, L.J.; Paz, N.M.

    1983-01-01

    Newspaper cartoons can graphically display the result of ambiguity in human speech; the result can be unexpected and funny. Likewise, computer analysis of natural language statements also needs to successfully resolve ambiguous situations. Computer techniques already developed use restricted world knowledge in resolving ambiguous language use. This paper illustrates how these techniques can be used in resolving ambiguous situations arising in cartoons. 8 references.

  8. Computational study of depth completion consistent with human bi-stable perception for ambiguous figures.

    Science.gov (United States)

    Mitsukura, Eiichi; Satoh, Shunji

    2018-03-01

    We propose a computational model that is consistent with human perception of depth in "ambiguous regions," in which no binocular disparity exists. Results obtained from our model reveal a new characteristic of depth perception. Random dot stereograms (RDS) are often used as examples because RDS provides sufficient disparity for depth calculation. A simple question confronts us: "How can we estimate the depth of a no-texture image region, such as one on white paper?" In such ambiguous regions, mathematical solutions related to binocular disparities are not unique or indefinite. We examine a mathematical description of depth completion that is consistent with human perception of depth for ambiguous regions. Using computer simulation, we demonstrate that resultant depth-maps qualitatively reproduce human depth perception of two kinds. The resultant depth maps produced using our model depend on the initial depth in the ambiguous region. Considering this dependence from psychological viewpoints, we conjecture that humans perceive completed surfaces that are affected by prior-stimuli corresponding to the initial condition of depth. We conducted psychological experiments to verify the model prediction. An ambiguous stimulus was presented after a prior stimulus removed ambiguity. The inter-stimulus interval (ISI) was inserted between the prior stimulus and post-stimulus. Results show that correlation of perception between the prior stimulus and post-stimulus depends on the ISI duration. Correlation is positive, negative, and nearly zero in the respective cases of short (0-200 ms), medium (200-400 ms), and long ISI (>400 ms). Furthermore, based on our model, we propose a computational model that can explain the dependence. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Improving Ambiguity Resolution for Medium Baselines Using Combined GPS and BDS Dual/Triple-Frequency Observations.

    Science.gov (United States)

    Gao, Wang; Gao, Chengfa; Pan, Shuguo; Wang, Denghui; Deng, Jiadong

    2015-10-30

    The regional constellation of the BeiDou navigation satellite system (BDS) has been providing continuous positioning, navigation and timing services since 27 December 2012, covering China and the surrounding area. Real-time kinematic (RTK) positioning with combined BDS and GPS observations is feasible. Besides, all satellites of BDS can transmit triple-frequency signals. Using the advantages of multi-pseudorange and carrier observations from multi-systems and multi-frequencies is expected to be of much benefit for ambiguity resolution (AR). We propose an integrated AR strategy for medium baselines by using the combined GPS and BDS dual/triple-frequency observations. In the method, firstly the extra-wide-lane (EWL) ambiguities of triple-frequency system, i.e., BDS, are determined first. Then the dual-frequency WL ambiguities of BDS and GPS were resolved with the geometry-based model by using the BDS ambiguity-fixed EWL observations. After that, basic (i.e., L1/L2 or B1/B2) ambiguities of BDS and GPS are estimated together with the so-called ionosphere-constrained model, where the ambiguity-fixed WL observations are added to enhance the model strength. During both of the WL and basic AR, a partial ambiguity fixing (PAF) strategy is adopted to weaken the negative influence of new-rising or low-elevation satellites. Experiments were conducted and presented, in which the GPS/BDS dual/triple-frequency data were collected in Nanjing and Zhengzhou of China, with the baseline distance varying from about 28.6 to 51.9 km. The results indicate that, compared to the single triple-frequency BDS system, the combined system can significantly enhance the AR model strength, and thus improve AR performance for medium baselines with a 75.7% reduction of initialization time on average. Besides, more accurate and stable positioning results can also be derived by using the combined GPS/BDS system.

  10. Midwestern Millennial University Students' Tolerance for Ambiguity in a Period of Complex World Conflicts

    Science.gov (United States)

    Mahdi, Ghada S.

    2012-01-01

    Though age and gender do not affect students' knowledge of global issues and associated ambiguity, the academic major of undergraduates did. Students' combined perceptions on knowledge of these issues and their associated ambiguities varied among the four academic groups of majors. Unlike teacher education majors and in combined other majors…

  11. Context sensitivity and ambiguity in component-based systems design

    Energy Technology Data Exchange (ETDEWEB)

    Bespalko, S.J.; Sindt, A.

    1997-10-01

    Designers of components-based, real-time systems need to guarantee to correctness of soft-ware and its output. Complexity of a system, and thus the propensity for error, is best characterized by the number of states a component can encounter. In many cases, large numbers of states arise where the processing is highly dependent on context. In these cases, states are often missed, leading to errors. The following are proposals for compactly specifying system states which allow the factoring of complex components into a control module and a semantic processing module. Further, the need for methods that allow for the explicit representation of ambiguity and uncertainty in the design of components is discussed. Presented herein are examples of real-world problems which are highly context-sensitive or are inherently ambiguous.

  12. Perceptions of racial confrontation: the role of color blindness and comment ambiguity.

    Science.gov (United States)

    Zou, Linda X; Dickter, Cheryl L

    2013-01-01

    Because of its emphasis on diminishing race and avoiding racial discourse, color-blind racial ideology has been suggested to have negative consequences for modern day race relations. The current research examined the influence of color blindness and the ambiguity of a prejudiced remark on perceptions of a racial minority group member who confronts the remark. One hundred thirteen White participants responded to a vignette depicting a White character making a prejudiced comment of variable ambiguity, after which a Black target character confronted the comment. Results demonstrated that the target confronter was perceived more negatively and as responding less appropriately by participants high in color blindness, and that this effect was particularly pronounced when participants responded to the ambiguous comment. Implications for the ways in which color blindness, as an accepted norm that is endorsed across legal and educational settings, can facilitate Whites' complicity in racial inequality are discussed.

  13. The association between tolerance for ambiguity and fear of negative evaluation: A study of engineering technology capstone courses

    Science.gov (United States)

    Dubikovsky, Sergey I.

    For many students in engineering and engineering technology programs in the US, senior capstone design courses require students to form a team, define a problem, and find a feasible technical solution to address this problem. Students must integrate the knowledge and skills acquired during their studies at the college or university level. These truly integrative design activities do not have a single "correct" solution. Instead, there is an array of solutions, many of which could be used to achieve the final result. This ambiguity can cause students to experience anxiety during the projects. This study examined the main topics: • To what extent is a social anxiety (measured as fear of negative evaluation) related to tolerance for ambiguity in senior engineering capstone courses? • How does exposure to ambiguity prior to and during capstone courses affect tolerance for ambiguity? The study looked at the standard educational practices to see if they have unintended consequences, such a social anxiety in dealing with ambiguity. Those consequences are highly undesirable because they reduce students' learning. It was hypothesized that the lecture-based approaches that are more common in the first three years of study would not prepare students for self-directed capstone courses because the students would rarely have experienced problem-based learning before. The study used a quantitative approach and examined students' perceptions of their tolerance for ambiguity, and social anxiety before and after their senior capstone design experience. A survey instrument was adapted to measure exposure to ambiguity, which was studied as a potential moderator of the relationship between social anxiety and tolerance for ambiguity. The study indicated that social anxiety, as measured by fear of negative evaluation, does not play a major role in capstone courses. The second finding is that a single course, even if it was administered as a problem-based senior class, failed to

  14. AMBIGUOUS JANUS OF MODERN DEMOCRACY

    Directory of Open Access Journals (Sweden)

    Volodymyr V. Khmil

    2016-06-01

    Full Text Available Purpose. The purpose of the research is to analyze ambiguous concept of  democracy as a phenomenon of political and social formation based on political and instrumental approach. As a result, some deep fundamentals of  human social existence and values as social life basis are blurred. Task. The task of  this investigation is to reveal the concept of democracy in its invariative philosophical  meaning and find the consequences of global social transformations towards social entropy. Methods of investigation. To implement the task an activity approach has been used with further possibility to single out two approaches - politological and philosophical. The focus on democracy from philosophic point of view makes possible to anticipate negative entropic processes that lead  to future ambiguity. Subject matter. Chaotic social processes can result in  ruined family, spiritual, legal and moral formations. Regulatory and legal paradigms are becoming less effective and entail disintegration of spiritual and value constituents of worldview causing necessary conditions for social entropy. Originality and Findings. Possible threats for human freedom that hinder the way to targeted  prospects of mankind have been considered in the paper. Thus, taking into account all positive aspects of democracy, it is simultaneously becoming the tool of continuous differentiation of society into tiny autonomous communities similar to nomadic atomization of society. The concept based on moral substantial existence basis as in “axis time” by K. Jaspers that can prevent social entropy resulting in world anthropologic catastrophes has been grounded in the present research.

  15. Simply Imagining Sunshine, Lollipops and Rainbows Will Not Budge the Bias: The Role of Ambiguity in Interpretive Bias Modification.

    Science.gov (United States)

    Clarke, Patrick J F; Nanthakumar, Shenooka; Notebaert, Lies; Holmes, Emily A; Blackwell, Simon E; Macleod, Colin

    2014-01-01

    Imagery-based interpretive bias modification (CBM-I) involves repeatedly imagining scenarios that are initially ambiguous before being resolved as either positive or negative in the last word/s. While the presence of such ambiguity is assumed to be important to achieve change in selective interpretation, it is also possible that the act of repeatedly imagining positive or negative events could produce such change in the absence of ambiguity. The present study sought to examine whether the ambiguity in imagery-based CBM-I is necessary to elicit change in interpretive bias, or, if the emotional content of the imagined scenarios is sufficient to produce such change. An imagery-based CBM-I task was delivered to participants in one of four conditions, where the valence of imagined scenarios were either positive or negative, and the ambiguity of the scenario was either present (until the last word/s) or the ambiguity was absent (emotional valence was evident from the start). Results indicate that only those who received scenarios in which the ambiguity was present acquired an interpretive bias consistent with the emotional valence of the scenarios, suggesting that the act of imagining positive or negative events will only influence patterns of interpretation when the emotional ambiguity is a consistent feature.

  16. Exploring the Relationship between Tolerance of Ambiguity of EFL Learners and Their Vocabulary Knowledge

    Science.gov (United States)

    Basöz, Tutku

    2015-01-01

    Learning a new language is akin to exploring an unknown land as ambiguous situations are prevalent in language learning. Ambiguity tolerance, which can hinder or facilitate language learning, is considered as an important learning style. The purpose of the present study was to understand how tolerant/intolerant EFL learners are of foreign language…

  17. Role Ambiguity and Self-Efficacy: The Moderating Effects of Goal Orientation and Procedural Justice

    Science.gov (United States)

    Li, Andrew; Bagger, Jessica

    2008-01-01

    The present study investigated variables that moderated the relationship between role ambiguity and self-efficacy. Results of a field study found support for the moderating role of learning goal orientation, such that the relationship between role ambiguity and self-efficacy was weaker when learning goal orientation was high. In addition, we found…

  18. The reciprocal dynamic model of career decision ambiguity tolerance with career indecision: A longitudinal three-wave investigation.

    Science.gov (United States)

    Xu, Hui; Tracey, Terence J G

    2017-10-01

    The current study investigated the dynamic interplay of career decision ambiguity tolerance and career indecision over 3 assessment times in a sample of college students (n = 583). While the previous research has repeatedly shown an association of career decision ambiguity tolerance with career indecision, the direction of this association has not been adequately assessed with longitudinal investigation. It was hypothesized in this study that there is a reciprocal pattern of career decision ambiguity tolerance leading to subsequent career indecision and career indecision leading to subsequent career decision ambiguity tolerance. Using a cross-lagged panel design, this study found support for the reciprocal pattern that aversion to ambiguity led to increased negative affect and choice anxiety in career decision making, while negative affect and choice anxiety led to increased aversion to ambiguity. Additionally, this study revealed that aversion led to decreased readiness for career decision making and readiness for career decision making led to increased interests in new information. The key findings were discussed with respect to the theoretical and clinical implications for career counseling along with limitations and suggestions for future research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. Resolution of potential ambiguities through farside angular structure: Semiclassical analysis

    International Nuclear Information System (INIS)

    Fricke, S.H.; Brandan, M.E.; McVoy, K.W.

    1988-01-01

    The optical potential fits summarized in the preceding paper are subjected to a semiclassical analysis of the Ford-Wheeler--Knoll-Schaeffer type. The important broad dips in their farside cross sections, which are essential in greatly reducing potential ambiguities, are found (in partial agreement with a suggestion of Goldberg's) to be mainly weak ''Airy'' or rainbow minima, that serve to identify deeply penetrating trajectories. The semiclassical analysis also permits the identification and understanding of a new category of discrete and continuous potential ambiguities, and suggests the manner in which specific features of the angular distributions (such as spacings and depths of various angular minima) determine the Woods-Saxon parameters found by a chi-squared search

  20. The ambiguity of US foreign policy towards Africa

    DEFF Research Database (Denmark)

    Olsen, Gorm Rye

    2017-01-01

    appear incoherent and ambiguous if judged narrowly on the expectation that it only aims to take care of US national security concerns and economic self-interests. The paper concludes that Africa was important to the United States during the presidencies of George W. Bush and Barack Obama because...

  1. GLONASS CDMA L3 ambiguity resolution and positioning

    NARCIS (Netherlands)

    Zaminpardaz, Safoora; Teunissen, P.J.G.; Nadarajah, Nandakumaran

    2016-01-01

    A first assessment of GLONASS CDMA L3 ambiguity resolution and positioning performance is provided. Our analyses are based on GLONASS L3 data from the satellite pair SVNs 755-801, received by two JAVAD receivers at Curtin University, Perth, Australia. In our analyses, four different versions of

  2. Do children exploit the Maxim of Antecedent in order to interpret ambiguous descriptions?

    Science.gov (United States)

    Surian, L

    1991-06-01

    Twenty Italian six-year-olds and 20 eight-year-olds were asked to interpret eight ambiguous and eight clear definite descriptions. All ambiguous descriptions could refer to three drawings, one of which had been described by the subjects immediately before the comprehension task. In half of the trials with ambiguous messages the children's interlocutor was present while the children were describing the drawings; in the other half he was absent. In both conditions subjects showed a preference for the referents they had already described, indicating that they applied egocentrically a comprehension strategy based on the Maxim of Antecedent (Jackson & Jacobs, 1982). Children's failures to differentiate their responses in the two conditions are considered to be due to difficulties in taking account of the given-new distinction for relevant information.

  3. Triple-Frequency GPS Precise Point Positioning Ambiguity Resolution Using Dual-Frequency Based IGS Precise Clock Products

    Directory of Open Access Journals (Sweden)

    Fei Liu

    2017-01-01

    Full Text Available With the availability of the third civil signal in the Global Positioning System, triple-frequency Precise Point Positioning ambiguity resolution methods have drawn increasing attention due to significantly reduced convergence time. However, the corresponding triple-frequency based precise clock products are not widely available and adopted by applications. Currently, most precise products are generated based on ionosphere-free combination of dual-frequency L1/L2 signals, which however are not consistent with the triple-frequency ionosphere-free carrier-phase measurements, resulting in inaccurate positioning and unstable float ambiguities. In this study, a GPS triple-frequency PPP ambiguity resolution method is developed using the widely used dual-frequency based clock products. In this method, the interfrequency clock biases between the triple-frequency and dual-frequency ionosphere-free carrier-phase measurements are first estimated and then applied to triple-frequency ionosphere-free carrier-phase measurements to obtain stable float ambiguities. After this, the wide-lane L2/L5 and wide-lane L1/L2 integer property of ambiguities are recovered by estimating the satellite fractional cycle biases. A test using a sparse network is conducted to verify the effectiveness of the method. The results show that the ambiguity resolution can be achieved in minutes even tens of seconds and the positioning accuracy is in decimeter level.

  4. "Pinch the Giraffe with the Glove" - Syntactic Ambiguity Resolution in Young Children

    OpenAIRE

    Young, Amy

    2014-01-01

    Previous research in language development focusing on the comprehension of ambiguous sentences has found that children are unable to use top-down information, such as referential context, to resolve the ambiguity. The present study aimed to discover whether children were also insensitive to a different form of top-down processing (the prior question). To do so, we conducted an experiment with 5- and 7-year-olds which involved playing with toys on a stage whilst listening to sound files which ...

  5. Strong-coupling study of the Gribov ambiguity in lattice Landau gauge

    International Nuclear Information System (INIS)

    Maas, Axel; Pawlowski, Jan M.; Spielmann, Daniel; Sternbeck, Andre; Smekal, Lorenz von

    2010-01-01

    We study the strong-coupling limit β=0 of lattice SU(2) Landau gauge Yang-Mills theory. In this limit the lattice spacing is infinite, and thus all momenta in physical units are infinitesimally small. Hence, the infrared behavior can be assessed at sufficiently large lattice momenta. Our results show that at the lattice volumes used here, the Gribov ambiguity has an enormous effect on the ghost propagator in all dimensions. This underlines the severity of the Gribov problem and calls for refined studies also at finite β. In turn, the gluon propagator only mildly depends on the Gribov ambiguity. (orig.)

  6. The indexing ambiguity in serial femtosecond crystallography (SFX) resolved using an expectation maximization algorithm.

    Science.gov (United States)

    Liu, Haiguang; Spence, John C H

    2014-11-01

    Crystallographic auto-indexing algorithms provide crystal orientations and unit-cell parameters and assign Miller indices based on the geometric relations between the Bragg peaks observed in diffraction patterns. However, if the Bravais symmetry is higher than the space-group symmetry, there will be multiple indexing options that are geometrically equivalent, and hence many ways to merge diffraction intensities from protein nanocrystals. Structure factor magnitudes from full reflections are required to resolve this ambiguity but only partial reflections are available from each XFEL shot, which must be merged to obtain full reflections from these 'stills'. To resolve this chicken-and-egg problem, an expectation maximization algorithm is described that iteratively constructs a model from the intensities recorded in the diffraction patterns as the indexing ambiguity is being resolved. The reconstructed model is then used to guide the resolution of the indexing ambiguity as feedback for the next iteration. Using both simulated and experimental data collected at an X-ray laser for photosystem I in the P63 space group (which supports a merohedral twinning indexing ambiguity), the method is validated.

  7. Ongoing neurogenesis in the adult dentate gyrus mediates behavioral responses to ambiguous threat cues.

    Directory of Open Access Journals (Sweden)

    Lucas R Glover

    2017-04-01

    Full Text Available Fear learning is highly adaptive if utilized in appropriate situations but can lead to generalized anxiety if applied too widely. A role of predictive cues in inhibiting fear generalization has been suggested by stress and fear learning studies, but the effects of partially predictive cues (ambiguous cues and the neuronal populations responsible for linking the predictive ability of cues and generalization of fear responses are unknown. Here, we show that inhibition of adult neurogenesis in the mouse dentate gyrus decreases hippocampal network activation and reduces defensive behavior to ambiguous threat cues but has neither of these effects if the same negative experience is reliably predicted. Additionally, we find that this ambiguity related to negative events determines their effect on fear generalization, that is, how the events affect future behavior under novel conditions. Both new neurons and glucocorticoid hormones are required for the enhancement of fear generalization following an unpredictably cued threat. Thus, adult neurogenesis plays a central role in the adaptive changes resulting from experience involving unpredictable or ambiguous threat cues, optimizing behavior in novel and uncertain situations.

  8. Simple explanation of the up-down ambiguity in πp and Kπ s-wave phase shifts

    International Nuclear Information System (INIS)

    Dean, N.W.; Chang, V.

    1976-01-01

    In both the π + π - and K + π - systems attempts to carry out a phase-shift analysis in the mass region below 1GeV/c 2 have consistently found two distinct solutions. This ''up-down'' ambiguity has been resolved by appealing to additional data and to arguments based on continuity in the energy variable. The letter shown that in both cases the up-down ambiguity is simply the lowest-order Gersten ambiguity, that is, the complex conjugation of the ''Barrelet zero''

  9. Dressed skeleton expansion and the coupling scale ambiguity problem

    International Nuclear Information System (INIS)

    Lu, Hung Jung.

    1992-09-01

    Perturbative expansions in quantum field theories are usually expressed in powers of a coupling constant. In principle, the infinite sum of the expansion series is independent of the renormalization scale of the coupling constant. In practice, there is a remnant dependence of the truncated series on the renormalization scale. This scale ambiguity can severely restrict the predictive power of theoretical calculations. The dressed skeleton expansion is developed as a calculational method which avoids the coupling scale ambiguity problem. In this method, physical quantities are expressed as functional expansions in terms of a coupling vertex function. The arguments of the vertex function are given by the physical momenta of each process. These physical momenta effectively replace the unspecified renormalization scale and eliminate the ambiguity problem. This method is applied to various field theoretical models and its main features and limitations are explored. For quantum chromodynamics, an expression for the running coupling constant of the three-gluon vertex is obtained. The effective coupling scale of this vertex is shown to be essentially given by μ 2 ∼ Q min 2 Q med 2 /Q max 2 where Q min 2 Q med 2 /Q max 2 are respectively the smallest, the next-to-smallest and the largest scale among the three gluon virtualities. This functional form suggests that the three-gluon vertex becomes non-perturbative at asymmetric momentum configurations. Implications for four-jet physics is discussed

  10. On the impact of GNSS ambiguity resolution: geometry, ionosphere, time and biases

    Science.gov (United States)

    Khodabandeh, A.; Teunissen, P. J. G.

    2018-06-01

    Integer ambiguity resolution (IAR) is the key to fast and precise GNSS positioning and navigation. Next to the positioning parameters, however, there are several other types of GNSS parameters that are of importance for a range of different applications like atmospheric sounding, instrumental calibrations or time transfer. As some of these parameters may still require pseudo-range data for their estimation, their response to IAR may differ significantly. To infer the impact of ambiguity resolution on the parameters, we show how the ambiguity-resolved double-differenced phase data propagate into the GNSS parameter solutions. For that purpose, we introduce a canonical decomposition of the GNSS network model that, through its decoupled and decorrelated nature, provides direct insight into which parameters, or functions thereof, gain from IAR and which do not. Next to this qualitative analysis, we present for the GNSS estimable parameters of geometry, ionosphere, timing and instrumental biases closed-form expressions of their IAR precision gains together with supporting numerical examples.

  11. Anxious and angry rejection sensitivity, social withdrawal, and retribution in high and low ambiguous situations.

    Science.gov (United States)

    Zimmer-Gembeck, Melanie J; Nesdale, Drew

    2013-02-01

    Rejection sensitivity (RS) is a tendency to expect, perceive, and overreact to rejection. Our objective was to examine whether anxious and angry RS have specific associations with negative social reactions, and whether responses are intensified in situations of high rejection ambiguity. In two studies, youth (N = 464 and N = 371) reported their RS and anticipated responses to social scenarios. In Study 1, all scenarios portrayed overt rejection events. In Study 2, participants were randomly assigned to conditions portraying overt or ambiguous rejection. Greater rejection expectation was associated with more negative reactions to rejection. Moreover, as expected, anxiety about rejection was uniquely associated with withdrawal, and anger about rejection was uniquely associated with retribution (i.e., reactive aggression). In the second study, RS persons responded more negatively than others to both overt and high ambiguous rejections, but retribution was intensified among participants high in rejection expectation when rejection was ambiguous, and withdrawal was intensified among participants high in anxious RS in overt rejection situations. Consistent with the revised RS model, there are different patterns of emotions, cognitions, and behaviors in response to high and low ambiguous rejection events, which are heightened in youth sensitive to rejection. © 2012, Wiley Periodicals, Inc.

  12. The ambiguity of simplicity in quantum and classical simulation

    Science.gov (United States)

    Aghamohammadi, Cina; Mahoney, John R.; Crutchfield, James P.

    2017-04-01

    A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the ;elegance; of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

  13. Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

    DEFF Research Database (Denmark)

    Munk, Claus; Rubtsov, Alexey Vladimirovich

    We solve a stock-bond-cash portfolio choice problem for a risk- and ambiguity-averse investor in a setting where the inflation rate and interest rates are stochastic. The expected inflation rate is unobservable, but the investor may learn about it from realized inflation and observed stock and bond...... prices. The investor is aware that his model for the observed inflation is potentially misspecified, and he seeks an investment strategy that maximizes his expected utility from real terminal wealth and is also robust to inflation model misspecification. We solve the corresponding robust Hamilton......-Jacobi-Bellman equation in closed form and derive and illustrate a number of interesting properties of the solution. For example, ambiguity aversion affects the optimal portfolio through the correlation of price level with the stock index, a bond, and the expected inflation rate. Furthermore, unlike other settings...

  14. Pricing risk and ambiguity : The effect of perspective taking

    NARCIS (Netherlands)

    Trautmann, S.T.; Schmidt, U.

    2012-01-01

    In the valuation of uncertain prospects, a difference is often observed between selling and buying perspectives. This paper distinguishes between risk (known probabilities) and ambiguity (unknown probabilities) in decisions under uncertainty and shows that the valuation disparity increases under

  15. The impact of uncertain threat on affective bias: Individual differences in response to ambiguity.

    Science.gov (United States)

    Neta, Maital; Cantelon, Julie; Haga, Zachary; Mahoney, Caroline R; Taylor, Holly A; Davis, F Caroline

    2017-12-01

    Individuals who operate under highly stressful conditions (e.g., military personnel and first responders) are often faced with the challenge of quickly interpreting ambiguous information in uncertain and threatening environments. When faced with ambiguity, it is likely adaptive to view potentially dangerous stimuli as threatening until contextual information proves otherwise. One laboratory-based paradigm that can be used to simulate uncertain threat is known as threat of shock (TOS), in which participants are told that they might receive mild but unpredictable electric shocks while performing an unrelated task. The uncertainty associated with this potential threat induces a state of emotional arousal that is not overwhelmingly stressful, but has widespread-both adaptive and maladaptive-effects on cognitive and affective function. For example, TOS is thought to enhance aversive processing and abolish positivity bias. Importantly, in certain situations (e.g., when walking home alone at night), this anxiety can promote an adaptive state of heightened vigilance and defense mobilization. In the present study, we used TOS to examine the effects of uncertain threat on valence bias, or the tendency to interpret ambiguous social cues as positive or negative. As predicted, we found that heightened emotional arousal elicited by TOS was associated with an increased tendency to interpret ambiguous cues negatively. Such negative interpretations are likely adaptive in situations in which threat detection is critical for survival and should override an individual's tendency to interpret ambiguity positively in safe contexts. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  16. Children’s and Adolescents’ Processing of Temporary Syntactic Ambiguity: An Eye Movement Study

    Directory of Open Access Journals (Sweden)

    Paul E. Engelhardt

    2014-01-01

    Full Text Available This study examined the eye movements of 24 children and adolescents as they read sentences containing temporary syntactic ambiguities. Prior research suggested that children primarily use grammatical information when making initial parsing decisions, and they tend to disregard semantic and contextual information. On each trial, participants read a garden path sentence (e.g., While the storm blew the boat sat in the shed, and, afterwards, they answered a comprehension question (e.g., Did the storm blow the boat?. The design was 2 × 2 (verb type × ambiguity repeated measures. Verb type was optionally transitive or reflexive, and sentences were ambiguous or unambiguous. Results showed no differences in first pass reading times at the disambiguating verb (e.g., sat. However, regressions did show a significant interaction. The unambiguous-reflexive condition had approximately half the number of regressions, suggesting less processing difficulty in this condition. Developmentally, we found that adolescents had significantly better comprehension, which seemed to be linked to the increased tendency to regress from the disambiguating word. Findings are consistent with the assumption that the processing architecture is more restricted in children compared to adolescents. In addition, results indicated that variance in ambiguity resolution was associated with interference control but not working memory.

  17. Ambiguity of the equivalence principle and Hawking's temperature

    NARCIS (Netherlands)

    Hooft, G. 't

    1984-01-01

    There are two inequivalent ways in which the laws of physics in a gravitational field can be related to the laws in an inertial frame, when quantum mechanical effects are taken into account. This leads to an ambiguity in the derivation of Hawking's radiation temperature for a black hole: it could be

  18. "What Happened?" Teaching Attribution Theory through Ambiguous Prompts

    Science.gov (United States)

    McArthur, John

    2011-01-01

    The concept of attribution, "the act of explaining why something happens or why a person acts a particular way," is typically an abstract concept. This 35-50-minute activity invites students to make a series of attributions by asking them "What happened?" in ambiguous scenes presented in class. Then, students retrospectively identify what…

  19. Participation or pedagogy?: Ambiguities and tensions surrounding the facilitation of children as researchers

    OpenAIRE

    Kim, Chae-Young

    2017-01-01

    Ambiguities and tensions can arise when children are facilitated to act as ‘primary researchers’ concerning whether this is primarily to support their ‘participation’ in knowledge production and, with the knowledge produced, in relevant decision-making processes or whether it is mainly for any educational benefits. This article considers these ambiguities and tensions theoretically and by using evidence from a study where English primary school children were supported to conduct their own res...

  20. A New Method for Single-Epoch Ambiguity Resolution with Indoor Pseudolite Positioning.

    Science.gov (United States)

    Li, Xin; Zhang, Peng; Guo, Jiming; Wang, Jinling; Qiu, Weining

    2017-04-21

    Ambiguity resolution (AR) is crucial for high-precision indoor pseudolite positioning. Due to the existing characteristics of the pseudolite positioning system, such as the geometry structure of the stationary pseudolite which is consistently invariant, the indoor signal is easy to interrupt and the first order linear truncation error cannot be ignored, and a new AR method based on the idea of the ambiguity function method (AFM) is proposed in this paper. The proposed method is a single-epoch and nonlinear method that is especially well-suited for indoor pseudolite positioning. Considering the very low computational efficiency of conventional AFM, we adopt an improved particle swarm optimization (IPSO) algorithm to search for the best solution in the coordinate domain, and variances of a least squares adjustment is conducted to ensure the reliability of the solving ambiguity. Several experiments, including static and kinematic tests, are conducted to verify the validity of the proposed AR method. Numerical results show that the IPSO significantly improved the computational efficiency of AFM and has a more elaborate search ability compared to the conventional grid searching method. For the indoor pseudolite system, which had an initial approximate coordinate precision better than 0.2 m, the AFM exhibited good performances in both static and kinematic tests. With the corrected ambiguity gained from our proposed method, indoor pseudolite positioning can achieve centimeter-level precision using a low-cost single-frequency software receiver.

  1. MOCCS: Clarifying DNA-binding motif ambiguity using ChIP-Seq data.

    Science.gov (United States)

    Ozaki, Haruka; Iwasaki, Wataru

    2016-08-01

    As a key mechanism of gene regulation, transcription factors (TFs) bind to DNA by recognizing specific short sequence patterns that are called DNA-binding motifs. A single TF can accept ambiguity within its DNA-binding motifs, which comprise both canonical (typical) and non-canonical motifs. Clarification of such DNA-binding motif ambiguity is crucial for revealing gene regulatory networks and evaluating mutations in cis-regulatory elements. Although chromatin immunoprecipitation sequencing (ChIP-seq) now provides abundant data on the genomic sequences to which a given TF binds, existing motif discovery methods are unable to directly answer whether a given TF can bind to a specific DNA-binding motif. Here, we report a method for clarifying the DNA-binding motif ambiguity, MOCCS. Given ChIP-Seq data of any TF, MOCCS comprehensively analyzes and describes every k-mer to which that TF binds. Analysis of simulated datasets revealed that MOCCS is applicable to various ChIP-Seq datasets, requiring only a few minutes per dataset. Application to the ENCODE ChIP-Seq datasets proved that MOCCS directly evaluates whether a given TF binds to each DNA-binding motif, even if known position weight matrix models do not provide sufficient information on DNA-binding motif ambiguity. Furthermore, users are not required to provide numerous parameters or background genomic sequence models that are typically unavailable. MOCCS is implemented in Perl and R and is freely available via https://github.com/yuifu/moccs. By complementing existing motif-discovery software, MOCCS will contribute to the basic understanding of how the genome controls diverse cellular processes via DNA-protein interactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Individual differences in aversion to ambiguity regarding medical tests and treatments: association with cancer screening cognitions.

    Science.gov (United States)

    Han, Paul K J; Williams, Andrew E; Haskins, Amy; Gutheil, Caitlin; Lucas, F Lee; Klein, William M P; Mazor, Kathleen M

    2014-12-01

    Aversion to "ambiguity"-uncertainty about the reliability, credibility, or adequacy of information-about medical tests and treatments is an important psychological response that varies among individuals, but little is known about its nature and extent. The purpose of this study was to examine how individual-level ambiguity aversion relates to important health cognitions related to different cancer screening tests. A survey of 1,074 adults, ages 40 to 70 years, was conducted in four integrated U.S. healthcare systems. The Ambiguity Aversion in Medicine (AA-Med) scale, a measure of individual differences in aversion to ambiguity (AA) about medical tests and treatments, was administered along with measures of several cancer screening-related cognitions: perceived benefits and harms of colonoscopy, mammography, and PSA screening, and ambivalence and future intentions regarding these tests. Multivariable analyses were conducted to assess the associations between AA-Med scores and cancer screening cognitions. Individual-level AA as assessed by the AA-Med scale was significantly associated (P ambiguity. Individual-level AA constitutes a measurable, wide-ranging cognitive bias against medical intervention, and more research is needed to elucidate its mechanisms and effects. ©2014 American Association for Cancer Research.

  3. Analysis of Location Ambiguity, GDOP and Station Layout of Threestation in Multilateration

    Directory of Open Access Journals (Sweden)

    Xu Zi Li

    2016-01-01

    Full Text Available In practice, the two-dimensional TDOA source location in the case of three stations would encounter the ambiguity problem of dual solutions. The relationship between distributions of location curve intersections, GDOP and receiving station layout is numerically analyzed, namely the distributions of location curve intersections and GDOP are determined by the receiving station layout, and the areas of two curve intersections are consistent with these of larger GDOP. These analysis results could serve as reference for avoiding or dealing with the ambiguity problem when multilateration is in application.

  4. On the robustness and possible accounts of ambiguity aversion

    NARCIS (Netherlands)

    Keren, G.; Gerritsen, L.E.M.

    1999-01-01

    Ambiguity aversion is one of the most robust phenomena documented in the decision making literature, though there are still disagreements concerning what constitutes an adequate account for its occurrence. We describe six experiments that shed additional light on the enigmatic phenomenon of

  5. The Development of Preschoolers' Appreciation of Communicative Ambiguity

    Science.gov (United States)

    Nilsen, Elizabeth S.; Graham, Susan A.

    2012-01-01

    Using a longitudinal design, preschoolers' appreciation of a listener's knowledge of the location of a hidden sticker after the listener was provided with an ambiguous or unambiguous description was assessed. Preschoolers (N = 34) were tested at 3 time points, each 6 months apart (4, 4 1/2, and 5 years). Eye gaze measures demonstrated that…

  6. Ambiguity in the Acquisition of Lexical Information

    OpenAIRE

    Vanderwende, Lucy

    1995-01-01

    This paper describes an approach to the automatic identification of lexical information in on-line dictionaries. This approach uses bootstrapping techniques, specifically so that ambiguity in the dictionary text can be treated properly. This approach consists of processing an on-line dictionary multiple times, each time refining the lexical information previously acquired and identifying new lexical information. The strength of this approach is that lexical information can be acquired from de...

  7. Ambiguity and uncertainty tolerance, need for cognition, and their association with stress. A study among Italian practicing physicians.

    Science.gov (United States)

    Iannello, Paola; Mottini, Anna; Tirelli, Simone; Riva, Silvia; Antonietti, Alessandro

    2017-01-01

    Medical practice is inherently ambiguous and uncertain. The physicians' ability to tolerate ambiguity and uncertainty has been proved to have a great impact on clinical practice. The primary aim of the present study was to test the hypothesis that higher degree of physicians' ambiguity and uncertainty intolerance and higher need for cognitive closure will predict higher work stress. Two hundred and twelve physicians (mean age = 42.94 years; SD = 10.72) from different medical specialties with different levels of expertise were administered a set of questionnaires measuring perceived levels of work-related stress, individual ability to tolerate ambiguity, stress deriving from uncertainty, and personal need for cognitive closure. A linear regression analysis was performed to examine which variables predict the perceived level of stress. The regression model was statistically significant [R 2  = .32; F(10,206) = 8.78, p ≤ .001], thus showing that, after controlling for gender and medical specialty, ambiguity and uncertainty tolerance, decisiveness (a dimension included in need for closure), and the years of practice were significant predictors of perceived work-related stress. Findings from the present study have some implications for medical education. Given the great impact that the individual ability to tolerate ambiguity and uncertainty has on the physicians' level of perceived work-related stress, it would be worth paying particular attention to such a skill in medical education settings. It would be crucial to introduce or to empower educational tools and strategies that could increase medical students' ability to tolerate ambiguity and uncertainty. JSQ: Job stress questionnaire; NFCS: Need for cognitive closure scale; PRU: Physicians' reactions to uncertainty; TFA: Tolerance for ambiguity.

  8. Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

    Directory of Open Access Journals (Sweden)

    Maria Paula Roncaglia-Denissen

    Full Text Available In the current event-related potential (ERP study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first. Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

  9. Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

    Science.gov (United States)

    Roncaglia-Denissen, Maria Paula; Schmidt-Kassow, Maren; Kotz, Sonja A

    2013-01-01

    In the current event-related potential (ERP) study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first). Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

  10. Implementation ambiguity: The fifth element long lost in uncertainty budgets for land biogeochemical modeling

    Science.gov (United States)

    Tang, J.; Riley, W. J.

    2015-12-01

    Previous studies have identified four major sources of predictive uncertainty in modeling land biogeochemical (BGC) processes: (1) imperfect initial conditions (e.g., assumption of preindustrial equilibrium); (2) imperfect boundary conditions (e.g., climate forcing data); (3) parameterization (type I equifinality); and (4) model structure (type II equifinality). As if that were not enough to cause substantial sleep loss in modelers, we propose here a fifth element of uncertainty that results from implementation ambiguity that occurs when the model's mathematical description is translated into computational code. We demonstrate the implementation ambiguity using the example of nitrogen down regulation, a necessary process in modeling carbon-climate feedbacks. We show that, depending on common land BGC model interpretations of the governing equations for mineral nitrogen, there are three different implementations of nitrogen down regulation. We coded these three implementations in the ACME land model (ALM), and explored how they lead to different preindustrial and contemporary land biogeochemical states and fluxes. We also show how this implementation ambiguity can lead to different carbon-climate feedback estimates across the RCP scenarios. We conclude by suggesting how to avoid such implementation ambiguity in ESM BGC models.

  11. Practical ambiguities during calculation of energy ratios and their impacts on life cycle assessment calculations

    International Nuclear Information System (INIS)

    Zhang, Yongli; Colosi, Lisa M.

    2013-01-01

    The energy ratio metrics are increasingly important means of assessing the efficiency of energy production for emerging biofuels platforms, making comparisons among multiple alternatives, and formulating policies to foster commercialization of sustainable energy systems. However, these metrics are susceptible to inadvertent or meaningful mathematical manipulation, whereby the same dataset can be used to compute dramatically different values of energy return on investment (EROI). In this study, previously published life cycle assessment (LCA) data for algal biofuels, corn ethanol, and switchgrass ethanol are used to demonstrate how seven seemingly reasonable EROI formulations give rise to a wide range of output values. It is then demonstrated that production of bioelectricity, and to a lesser extent, other co-products, significantly increases EROI ambiguity. Overall, the EROI results are used to illustrate how EROI ambiguity makes it difficult to properly assess the energetic favorability of a particular energy system or to make accurate comparisons among multiple systems. It is then recommended that all future biofuels studies restrict themselves to usage of “EROI 1 ”, which documents all input and outputs as explicit terms, to mitigate EROI ambiguity and improve policy decision-making. - Highlights: ► Energy ratios are appealing but potentially ambiguous sustainability metrics. ► Various ratio formulations can give different metrics for the same dataset. ► Production of electricity or other co-products exacerbates ratio ambiguity

  12. Optimal combination of illusory and luminance-defined 3-D surfaces: A role for ambiguity.

    Science.gov (United States)

    Hartle, Brittney; Wilcox, Laurie M; Murray, Richard F

    2018-04-01

    The shape of the illusory surface in stereoscopic Kanizsa figures is determined by the interpolation of depth from the luminance edges of adjacent inducing elements. Despite ambiguity in the position of illusory boundaries, observers reliably perceive a coherent three-dimensional (3-D) surface. However, this ambiguity may contribute additional uncertainty to the depth percept beyond what is expected from measurement noise alone. We evaluated the intrinsic ambiguity of illusory boundaries by using a cue-combination paradigm to measure the reliability of depth percepts elicited by stereoscopic illusory surfaces. We assessed the accuracy and precision of depth percepts using 3-D Kanizsa figures relative to luminance-defined surfaces. The location of the surface peak was defined by illusory boundaries, luminance-defined edges, or both. Accuracy and precision were assessed using a depth-discrimination paradigm. A maximum likelihood linear cue combination model was used to evaluate the relative contribution of illusory and luminance-defined signals to the perceived depth of the combined surface. Our analysis showed that the standard deviation of depth estimates was consistent with an optimal cue combination model, but the points of subjective equality indicated that observers consistently underweighted the contribution of illusory boundaries. This systematic underweighting may reflect a combination rule that attributes additional intrinsic ambiguity to the location of the illusory boundary. Although previous studies show that illusory and luminance-defined contours share many perceptual similarities, our model suggests that ambiguity plays a larger role in the perceptual representation of illusory contours than of luminance-defined contours.

  13. Analytical Review of Contemporary Fatwas in Resolving Biomedical Issues Over Gender Ambiguity.

    Science.gov (United States)

    Zabidi, Taqwa

    2018-04-21

    Issues of gender ambiguity have been discussed over time from both Islamic and medical perspectives. In Islam, these issues are typically considered in the context of khunūthah (literally translated as hermaphroditism). While biomedical studies have appeared to provide a large amount of information on abnormal human biological development, i.e. Disorders of Sex Development (DSDs). However, the connection between these two fields has been given little attention. This research aims to determine the Islamic underpinnings through the fatwa around the globe. Thus, institutional fatwa organisations among Sunni schools of thought at the international, regional and national levels are observed. The fatwas regarding the management of individuals with gender ambiguity, not specifically on DSDs, are chosen and presented accordingly. Based on the findings, the sporadic fatwas from different parts of the world delineate the issue of sex ambiguity and seem to be able to provide general guidelines for management of Muslim patients with DSDs. Three common aspects have been discussed including the methodology of gender assignment, the decision-making process and the surgical and hormonal treatments.

  14. Target Tracking Using SePDAF under Ambiguous Angles for Distributed Array Radar

    Science.gov (United States)

    Long, Teng; Zhang, Honggang; Zeng, Tao; Chen, Xinliang; Liu, Quanhua; Zheng, Le

    2016-01-01

    Distributed array radar can improve radar detection capability and measurement accuracy. However, it will suffer cyclic ambiguity in its angle estimates according to the spatial Nyquist sampling theorem since the large sparse array is undersampling. Consequently, the state estimation accuracy and track validity probability degrades when the ambiguous angles are directly used for target tracking. This paper proposes a second probability data association filter (SePDAF)-based tracking method for distributed array radar. Firstly, the target motion model and radar measurement model is built. Secondly, the fusion result of each radar’s estimation is employed to the extended Kalman filter (EKF) to finish the first filtering. Thirdly, taking this result as prior knowledge, and associating with the array-processed ambiguous angles, the SePDAF is applied to accomplish the second filtering, and then achieving a high accuracy and stable trajectory with relatively low computational complexity. Moreover, the azimuth filtering accuracy will be promoted dramatically and the position filtering accuracy will also improve. Finally, simulations illustrate the effectiveness of the proposed method. PMID:27618058

  15. Cancellation of renormalon ambiguities in the heavy quark effective theory

    International Nuclear Information System (INIS)

    Neubert, M.; Sachrajda, C.T.

    1995-01-01

    Recently, it has been shown that the concept of the pole mass of a heavy quark becomes ambiguous beyond perturbation theory, because of the presence of infrared renormalons. We argue that the predictions of the heavy quark effective theory, whose construction is based on the pole mass, are free of such ambiguities. In the 1/m Q expansion of physical quantities, infrared and ultraviolet renormalons compensate each other between coefficient functions and matrix elements. We trace the appearance of these compensations for current-induced exclusive heavy-to-heavy and heavy-to-light transitions, and for inclusive decays of heavy hadrons. In particular, we show that the structure of the heavy quark expansion is not obscured by renormalons, and none of the predictions of the heavy quark effective theory are invalidated. ((orig.))

  16. Executive function and intelligence in the resolution of temporary syntactic ambiguity: an individual differences investigation.

    Science.gov (United States)

    Engelhardt, Paul E; Nigg, Joel T; Ferreira, Fernanda

    2017-07-01

    In the current study, we examined the role of intelligence and executive functions in the resolution of temporary syntactic ambiguity using an individual differences approach. Data were collected from 174 adolescents and adults who completed a battery of cognitive tests as well as a sentence comprehension task. The critical items for the comprehension task consisted of object/subject garden paths (e.g., While Anna dressed the baby that was small and cute played in the crib), and participants answered a comprehension question (e.g., Did Anna dress the baby?) following each one. Previous studies have shown that garden-path misinterpretations tend to persist into final interpretations. Results showed that both intelligence and processing speed interacted with ambiguity. Individuals with higher intelligence and faster processing were more likely to answer the comprehension questions correctly and, specifically, following ambiguous as opposed to unambiguous sentences. Inhibition produced a marginal effect, but the variance in inhibition was largely shared with intelligence. Conclusions focus on the role of individual differences in cognitive ability and their impact on syntactic ambiguity resolution.

  17. Pragmatic Failure and Referential Ambiguity when Attorneys Ask Child Witnesses "Do You Know/Remember" Questions.

    Science.gov (United States)

    Evans, Angela D; Stolzenberg, Stacia N; Lyon, Thomas D

    2017-05-01

    "Do you know" and "Do you remember" (DYK/R) questions explicitly ask whether one knows or remembers some information while implicitly asking for that information. This study examined how 104 4- to 9-year-old children testifying in child sexual abuse cases responded to DYK/R wh- and yes/no questions. When asked DYK/R questions containing an implicit wh- question requesting information, children often provided unelaborated "Yes" responses. Attorneys' follow-up questions suggested that children usually misunderstood the pragmatics of the questions. When DYK/R questions contained an implicit yes/no question, unelaborated "Yes" or "No" responses could be responding to the explicit or the implicit questions resulting in referentially ambiguous responses. Children often provided referentially ambiguous responses and attorneys usually failed to disambiguate children's answers. Although pragmatic failure following DYK/R wh- questions decreased with age, the likelihood of referential ambiguity following DYK/R yes/no questions did not. The results highlight the risks of serious miscommunications caused by pragmatic misunderstanding and referential ambiguity when children testify.

  18. The dynamic interplay among EFL learners’ ambiguity tolerance, adaptability, cultural intelligence, learning approach, and language achievement

    Directory of Open Access Journals (Sweden)

    Shadi Alahdadi

    2017-01-01

    Full Text Available A key objective of education is to prepare individuals to be fully-functioning learners. This entails developing the cognitive, metacognitive, motivational, cultural, and emotional competencies. The present study aimed to examine the interrelationships among adaptability, tolerance of ambiguity, cultural intelligence, learning approach, and language achievement as manifestations of the above competencies within a single model. The participants comprised one hundred eighty BA and MA Iranian university students studying English language teaching and translation. The instruments used in this study consisted of the translated versions of four questionnaires: second language tolerance of ambiguity scale, adaptability taken from emotional intelligence inventory, cultural intelligence (CQ inventory, and the revised study process questionnaire measuring surface and deep learning. The results estimated via structural equation modeling (SEM revealed that the proposed model containing the variables under study had a good fit with the data. It was found that all the variables except adaptability directly influenced language achievement with deep approach having the highest impact and ambiguity tolerance having the lowest influence. In addition, ambiguity tolerance was a positive and significant predictor of deep approach. CQ was found to be under the influence of both ambiguity tolerance and adaptability. The findings were discussed in the light of the yielded results.

  19. Ambiguity Function and Resolution Characteristic Analysis of DVB-S Signal for Passive Radar

    Directory of Open Access Journals (Sweden)

    Jin Wei

    2012-12-01

    Full Text Available This paper gives the performance research on the ambiguity function and resolution of passive radar based on DVB-S (Digital Video Broadcasting-Satellite signal. The radar system structure and signal model of DVB-S signal are firstly studied, then the ambiguity function of DVB-S signal is analyzed. At last, it has been obtained how the bistatic radar position impacts the resolution. Theoretical analyses and computer simulation show that DVB-S signal is applicable as an illuminator for passive radar.

  20. Selective impairment of decision making under ambiguity in alexithymia.

    Science.gov (United States)

    Zhang, Lei; Wang, Xue; Zhu, Yu; Li, Hongchen; Zhu, Chunyan; Yu, Fengqiong; Wang, Kai

    2017-11-28

    Alexithymia is characterised by difficulties identifying and describing emotions. Few studies have investigated how alexithymia influences decision-making under different conditions (ambiguity and risk). This study aimed to examine whether alexithymia contributes to impairment in decision-making. This study included 42 participants with high scores in the Chinese version of Toronto Alexithymia Scale (alexithymia group), and 44 matched subjects with low scores (control group). Decision-making was measured using the Iowa Gambling Task (IGT) and the Game of Dice Task (GDT). The main findings of this study revealed selective deficits in IGT performance for the alexithymia group, while GDT performance was unimpaired when compared with the control group. In IGT, total netscores were lower for the alexithymia group compared to the control group, particularly with regard to block 5. Moreover, the alexithymia individuals selected significantly more adverse cards than the controls, indicating significant decision-making impairments. Alexithymia selectively influences decision-making under ambiguity.

  1. On the reconstruction of a unitary matrix from its moduli. Existence of continuous ambiguities

    International Nuclear Information System (INIS)

    Auberson, G.

    1989-01-01

    It is shown that, for an n x n unitary matrix with n ≥ 4, the knowledge of the moduli of its elements is not always sufficient to determine this matrix up to 'trivial' or 'discrete' ambiguities. Using a parametrization a la Kobayashi-Maskawa in the case n=4, we exhibit various configurations of the moduli for which a continuous ambiguity appears (i.e., some non-trivial phase remains free). (orig.)

  2. In the Face of Uncertainty: A Twin Study of Ambiguous Information, Anxiety and Depression in Children

    Science.gov (United States)

    Eley, Thalia C.; Gregory, Alice M.; Lau, Jennifer Y. F.; McGuffin, Peter; Napolitano, Maria; Rijsdijk, Fruhling V.; Clark, David M.

    2008-01-01

    Anxiety and depression share genetic influences, and have been associated with similar cognitive biases. Psychological theories of anxiety and depression highlight threat interpretations of ambiguity. Little is known about whether genes influence cognitive style, or its links to symptoms. We assessed ambiguous word and scenario interpretations,…

  3. FAST INTEGER AMBIGUITY RESOLUTION IN GPS KINEMATIC POSITIONING USING LEFT NULL SPACE AND MULTI-TIME (INVERSE PAIRED CHOLESKY DECORRELATION

    Directory of Open Access Journals (Sweden)

    Rong Duan

    Full Text Available Aiming at the problems that huge amount of computation in ambiguity resolution with multiple epochs and high-order matrix inversion occurred in the GPS kinematic relative positioning, a modified algorithm for fast integer ambiguity resolution is proposed. Firstly, Singular Value Decomposition (SVD is applied to construct the left null space matrix in order to eliminate the baselines components, which is able to separate ambiguity parameters from the position parameters efficiently. Kalman filter is applied only to estimate the ambiguity parameters so that the real-time ambiguity float solution is obtained. Then, sorting and multi-time (inverse paired Cholesky decomposition are adopted for decorrelation of ambiguity. After diagonal elements preprocessing and diagonal elements sorting according to the results of Cholesky decomposition, the efficiency of decomposition and decorrelation is improved. Lastly, the integer search algorithm implemented in LAMBDA method is used for searching the integer ambiguity. To verify the validity and efficacy of the proposed algorithm, static and kinematic tests are carried out. Experimental results show that this algorithm has good performance of decorrelation and precision of float solution, with computation speed also increased effectively. The final positioning accuracy result with static baseline error less than 1 cm and kinematic error less than 2 cm, which indicates that it can be used for fast kinematic positioning of high precision carrier.

  4. Precise orbit determination of the Sentinel-3A altimetry satellite using ambiguity-fixed GPS carrier phase observations

    Science.gov (United States)

    Montenbruck, Oliver; Hackel, Stefan; Jäggi, Adrian

    2017-11-01

    The Sentinel-3 mission takes routine measurements of sea surface heights and depends crucially on accurate and precise knowledge of the spacecraft. Orbit determination with a targeted uncertainty of less than 2 cm in radial direction is supported through an onboard Global Positioning System (GPS) receiver, a Doppler Orbitography and Radiopositioning Integrated by Satellite instrument, and a complementary laser retroreflector for satellite laser ranging. Within this study, the potential of ambiguity fixing for GPS-only precise orbit determination (POD) of the Sentinel-3 spacecraft is assessed. A refined strategy for carrier phase generation out of low-level measurements is employed to cope with half-cycle ambiguities in the tracking of the Sentinel-3 GPS receiver that have so far inhibited ambiguity-fixed POD solutions. Rather than explicitly fixing double-difference phase ambiguities with respect to a network of terrestrial reference stations, a single-receiver ambiguity resolution concept is employed that builds on dedicated GPS orbit, clock, and wide-lane bias products provided by the CNES/CLS (Centre National d'Études Spatiales/Collecte Localisation Satellites) analysis center of the International GNSS Service. Compared to float ambiguity solutions, a notably improved precision can be inferred from laser ranging residuals. These decrease from roughly 9 mm down to 5 mm standard deviation for high-grade stations on average over low and high elevations. Furthermore, the ambiguity-fixed orbits offer a substantially improved cross-track accuracy and help to identify lateral offsets in the GPS antenna or center-of-mass (CoM) location. With respect to altimetry, the improved orbit precision also benefits the global consistency of sea surface measurements. However, modeling of the absolute height continues to rely on proper dynamical models for the spacecraft motion as well as ground calibrations for the relative position of the altimeter reference point and the CoM.

  5. Doctoral Dissertation Defences: Performing Ambiguity between Ceremony and Assessment

    NARCIS (Netherlands)

    van der Heide, Arjen; Rufas, Alix; Supper, Alexandra

    2016-01-01

    Dissertation defenses are ambiguous affairs, which mark both the end of a long process of doctoral education and the inauguration of a doctoral candidate into a body of experts. At Maastricht University (and other Dutch universities), the decision to award a doctoral degree is made on the basis of

  6. How to Capture and Present Complexity, Ambivalence and Ambiguity

    DEFF Research Database (Denmark)

    Ooi, Can-Seng

    Bakhtin was a literary theorist and was the widely acknowledged father of dialogism. This working paper shows how Bakhtin and dialogism can be used to capture complexity, ambivalence and ambiguity in the social world. In following the spirit of dialogism, I will refer to my own research experiences...

  7. Resolving ambiguities in reconstructed grain maps using discrete tomography

    DEFF Research Database (Denmark)

    Alpers, A.; Knudsen, E.; Poulsen, H.F.

    2005-01-01

    reconstruct the image from diffraction data, but they are often unable to assign unambiguous values to all pixels. We present an approach that resolves these ambiguous pixels by using a Monte Carlo technique that exploits the discrete nature of the problem and utilizes proven methods of discrete tomography...

  8. Translation Ambiguity but Not Word Class Predicts Translation Performance

    Science.gov (United States)

    Prior, Anat; Kroll, Judith F.; Macwhinney, Brian

    2013-01-01

    We investigated the influence of word class and translation ambiguity on cross-linguistic representation and processing. Bilingual speakers of English and Spanish performed translation production and translation recognition tasks on nouns and verbs in both languages. Words either had a single translation or more than one translation. Translation…

  9. Aggression in Teachers is Related to Role Conflict and Role Ambiguity as Occupational Stress.

    Science.gov (United States)

    Kanchika, Masaru; Iwasaki, Shinichi; Konish, Akihito; Deguchi, Yasuhiko; Kobayashi, Yumi; Nakada, Akihiro; Inoue, Koki

    2015-12-01

    Aggression in the workplace is increasingly recognized as a serious problem, but there are few studies about worker aggression toward outsiders in the workplace. We investigated the association between aggression and occupational stress among teachers. This was a cross-sectional study of 1583 teachers, principals, and vice-principals. Aggression was measured using the Japanese version of the Buss-Perry Aggression Questionnaire (BAQ). The survey respondents were classified into tertiles according to the BAQ score. The high BAQ group was defined as the upper tertile for the BAQ total score (BAQ total score 625). Occupational stress was measured using the Japanese version of the Generic Job Stress Questionnaire. Comparisons among the groups were performed using multiple logistic regression analysis. Of the 1583 respondents, 488 were included in the high BAQ group. After adjusting for demographic and occupational variables, high role conflict and role ambiguity were significantly associated with belonging to the high BAQ group. In subscales of the BAQ, high role conflict and role ambiguity related to high levels of hostility, and physical aggression. Occupational stress such as role conflict and role ambiguity was associated with aggression among teachers. It is necessary to reduce problems which relates to role conflict and role ambiguity for preventing teachers' aggression.

  10. Ambiguity and Inconsistencies in Mathematics Spoken in the Classroom: The Need for Teacher Training and Rules for Communication of Mathematics

    Science.gov (United States)

    Isaacson, M.D.; Srinivasan, S.; Lloyd, L.L.

    2012-01-01

    Mathematics has the potential for being spoken ambiguously. This is problematic for many students, in particular those who have disabilities that inhibit processing of printed material. This paper documents the magnitude of potential ambiguity arising from textbooks and provides a measure of the degree to which potential ambiguity is actualized…

  11. Long-Duration Spaceflight Increases Depth Ambiguity of Reversible Perspective Figures

    Science.gov (United States)

    Clément, Gilles; Allaway, Heather C. M.; Demel, Michael; Golemis, Adrianos; Kindrat, Alexandra N.; Melinyshyn, Alexander N.; Merali, Tahir; Thirsk, Robert

    2015-01-01

    The objective of this study was to investigate depth perception in astronauts during and after spaceflight by studying their sensitivity to reversible perspective figures in which two-dimensional images could elicit two possible depth representations. Other ambiguous figures that did not give rise to a perception of illusory depth were used as controls. Six astronauts and 14 subjects were tested in the laboratory during three sessions for evaluating the variability of their responses in normal gravity. The six astronauts were then tested during four sessions while on board the International Space Station for 5–6 months. They were finally tested immediately after return to Earth and up to one week later. The reaction time decreased throughout the sessions, thus indicating a learning effect. However, the time to first percept reversal and the number of reversals were not different in orbit and after the flight compared to before the flight. On Earth, when watching depth-ambiguous perspective figures, all subjects reported seeing one three-dimensional interpretation more often than the other, i.e. a ratio of about 70–30%. In weightlessness this asymmetry gradually disappeared and after 3 months in orbit both interpretations were seen for the same duration. These results indicate that the perception of “illusory” depth is altered in astronauts during spaceflight. This increased depth ambiguity is attributed to the lack of the gravitational reference and the eye-ground elevation for interpreting perspective depth cues. PMID:26146839

  12. Long-Duration Spaceflight Increases Depth Ambiguity of Reversible Perspective Figures.

    Directory of Open Access Journals (Sweden)

    Gilles Clément

    Full Text Available The objective of this study was to investigate depth perception in astronauts during and after spaceflight by studying their sensitivity to reversible perspective figures in which two-dimensional images could elicit two possible depth representations. Other ambiguous figures that did not give rise to a perception of illusory depth were used as controls. Six astronauts and 14 subjects were tested in the laboratory during three sessions for evaluating the variability of their responses in normal gravity. The six astronauts were then tested during four sessions while on board the International Space Station for 5-6 months. They were finally tested immediately after return to Earth and up to one week later. The reaction time decreased throughout the sessions, thus indicating a learning effect. However, the time to first percept reversal and the number of reversals were not different in orbit and after the flight compared to before the flight. On Earth, when watching depth-ambiguous perspective figures, all subjects reported seeing one three-dimensional interpretation more often than the other, i.e. a ratio of about 70-30%. In weightlessness this asymmetry gradually disappeared and after 3 months in orbit both interpretations were seen for the same duration. These results indicate that the perception of "illusory" depth is altered in astronauts during spaceflight. This increased depth ambiguity is attributed to the lack of the gravitational reference and the eye-ground elevation for interpreting perspective depth cues.

  13. Pointwise Partial Information Decomposition Using the Specificity and Ambiguity Lattices

    Science.gov (United States)

    Finn, Conor; Lizier, Joseph

    2018-04-01

    What are the distinct ways in which a set of predictor variables can provide information about a target variable? When does a variable provide unique information, when do variables share redundant information, and when do variables combine synergistically to provide complementary information? The redundancy lattice from the partial information decomposition of Williams and Beer provided a promising glimpse at the answer to these questions. However, this structure was constructed using a much criticised measure of redundant information, and despite sustained research, no completely satisfactory replacement measure has been proposed. In this paper, we take a different approach, applying the axiomatic derivation of the redundancy lattice to a single realisation from a set of discrete variables. To overcome the difficulty associated with signed pointwise mutual information, we apply this decomposition separately to the unsigned entropic components of pointwise mutual information which we refer to as the specificity and ambiguity. This yields a separate redundancy lattice for each component. Then based upon an operational interpretation of redundancy, we define measures of redundant specificity and ambiguity enabling us to evaluate the partial information atoms in each lattice. These atoms can be recombined to yield the sought-after multivariate information decomposition. We apply this framework to canonical examples from the literature and discuss the results and the various properties of the decomposition. In particular, the pointwise decomposition using specificity and ambiguity satisfies a chain rule over target variables, which provides new insights into the so-called two-bit-copy example.

  14. Teaching weight to explicitly address language ambiguities and conceptual difficulties

    Science.gov (United States)

    Taibu, Rex; Schuster, David; Rudge, David

    2017-06-01

    Language ambiguities in concept meanings can exacerbate student learning difficulties and conceptual understanding of physics concepts. This is especially true for the concept of "weight," which has multiple meanings in both scientific and everyday usage. The term weight has been defined in several different ways, with nuances, but in textbooks and teaching the term is almost always defined in one of two ways: operationally either as the contact force between an object and a measuring scale or as the gravitational force on an object due to some other body such as Earth. The use of the same name for different concepts leads to much confusion, especially in accelerating situations, and to conflicting notions of "weightlessness" in free fall situations. In the present paper, we share an innovative approach that initially avoids the term weight entirely while teaching the physics of each situation, and then teaches the language ambiguities explicitly. We developed an instructional module with this approach and implemented it over two terms in three sections of an introductory physics course for preservice elementary teachers. Learning gains for content understanding were assessed using pretests and post-tests. Participants achieved remarkably high gains for both static and accelerating situations. Surveys pre- and postinstruction showed substantially improved appreciation of language issues and ambiguities associated with weight, weightlessness, and free fall. Interviews with instructors teaching the module provided additional insight into the advantages and teaching demands of the new approach.

  15. Ambiguously Divided Responsibilities across Government Spheres: How they Impact the Policy Process and Result in Coordination Problems in the Case of Poland

    Directory of Open Access Journals (Sweden)

    Hans Dubois

    2014-07-01

    Full Text Available Empirical studies in decentralized settings associate ambiguities in the division of responsibilities between government spheres with coordination problems. This study explores the mechanisms behind this association, mainly drawing on in-depth interviews with local government officials in Poland. A typology emerges from the data. Ambiguities can refer to the policy content, but also to the rationale behind responsibilities. They may be real or perceived. The agent who perceives the ambiguities can be close to public administration (internal or further removed from it (external. External ambiguities mostly inhibit front-room stages of the policy cycle, while external ambiguities impede back-room stages. Through different paths, they contribute to tensions between government spheres, obstructing cooperation needed to address the ambiguities. Overall, the article contributes to a better understanding of the policy process in decentralized settings, unwraps the dynamic causal framework surrounding the ambiguities, and highlights the role of perceptions, not only by the electorate, but by public officials in particular.

  16. Varying acoustic-phonemic ambiguity reveals that talker normalization is obligatory in speech processing.

    Science.gov (United States)

    Choi, Ja Young; Hu, Elly R; Perrachione, Tyler K

    2018-04-01

    The nondeterministic relationship between speech acoustics and abstract phonemic representations imposes a challenge for listeners to maintain perceptual constancy despite the highly variable acoustic realization of speech. Talker normalization facilitates speech processing by reducing the degrees of freedom for mapping between encountered speech and phonemic representations. While this process has been proposed to facilitate the perception of ambiguous speech sounds, it is currently unknown whether talker normalization is affected by the degree of potential ambiguity in acoustic-phonemic mapping. We explored the effects of talker normalization on speech processing in a series of speeded classification paradigms, parametrically manipulating the potential for inconsistent acoustic-phonemic relationships across talkers for both consonants and vowels. Listeners identified words with varying potential acoustic-phonemic ambiguity across talkers (e.g., beet/boat vs. boot/boat) spoken by single or mixed talkers. Auditory categorization of words was always slower when listening to mixed talkers compared to a single talker, even when there was no potential acoustic ambiguity between target sounds. Moreover, the processing cost imposed by mixed talkers was greatest when words had the most potential acoustic-phonemic overlap across talkers. Models of acoustic dissimilarity between target speech sounds did not account for the pattern of results. These results suggest (a) that talker normalization incurs the greatest processing cost when disambiguating highly confusable sounds and (b) that talker normalization appears to be an obligatory component of speech perception, taking place even when the acoustic-phonemic relationships across sounds are unambiguous.

  17. Is Multilingualism Linked to a Higher Tolerance of Ambiguity?

    Science.gov (United States)

    DeWaele, Jean-Marc; Wei, Li

    2013-01-01

    The present study investigates the link between multilingualism and the personality trait Tolerance of Ambiguity (TA) among 2158 mono-, bi- and multilinguals. Monolinguals and bilinguals scored significantly lower on TA compared to multilinguals. A high level of global proficiency of various languages was linked to higher TA scores. A stay abroad…

  18. Operational Implementation of ERS Satellite Scatterometer Wind Retrieval and Ambiguity Removal

    National Research Council Canada - National Science Library

    Martin, Christy

    1996-01-01

    .... The European Space Agency uses this data to generate a wind Fast Delivery Product (FDP). However, this product is insufficient in its resolution of the scatterometer's inherent wind direction ambiguity...

  19. Seven Types of Ambiguity in Evaluating the Impact of Humanities Provision in Undergraduate Medicine Curricula.

    Science.gov (United States)

    Bleakley, Alan

    2015-12-01

    Inclusion of the humanities in undergraduate medicine curricula remains controversial. Skeptics have placed the burden of proof of effectiveness upon the shoulders of advocates, but this may lead to pursuing measurement of the immeasurable, deflecting attention away from the more pressing task of defining what we mean by the humanities in medicine. While humanities input can offer a fundamental critical counterweight to a potentially reductive biomedical science education, a new wave of thinking suggests that the kinds of arts and humanities currently used in medical education are neither radical nor critical enough to have a deep effect on students' learning and may need to be reformulated. The humanities can certainly educate for tolerance of ambiguity as a basis to learning democratic habits for contemporary team-based clinical work. William Empson's 'seven types of ambiguity' model for analyzing poetry is transposed to medical education to: (a) formulate seven values proffered by the humanities for improving medical education; (b) offer seven ways of measuring impact of medical humanities provision, thereby reducing ambiguity; and (c) --as a counterweight to (b) - celebrate seven types of ambiguity in contemporary medical humanities that critically reconsider issues of proof of impact.

  20. Differential age effects on lexical ambiguity resolution mechanisms

    OpenAIRE

    Lee, Chia-lin; Federmeier, Kara D.

    2010-01-01

    Multiple neurocognitive subsystems are involved in resolving lexical ambiguity under different circumstances. We examined how processing in these subsystems changes with normal aging by comparing ERP responses to homographs and unambiguous words completing congruent sentences (with both semantic and syntactic contextual information) or syntactic prose (syntactic information only). Like young adults in prior work, older adults elicited more negative N400s to homographs in congruent sentences, ...

  1. Managing stakeholder ambiguity in the international mining sector: the case of Goldcorp Inc. in Guatemala

    OpenAIRE

    Mathieson, Travis Sinclair

    2015-01-01

    Canadian mining companies operating in the developing world face a complex business environment where substantial stakeholder ambiguity must be managed. Stakeholder ambiguity occurs when stakeholders interpret company actions or information they receive in different ways depending on their individual goals, demands, and opinions. Through interviews with company managers and leaders of civil-society organizations, this study endeavours to determine how Canadian-based senior mining company G...

  2. Textbook Presentations of Weight: Conceptual Difficulties and Language Ambiguities

    Science.gov (United States)

    Taibu, Rex; Rudge, David; Schuster, David

    2015-01-01

    The term "weight" has multiple related meanings in both scientific and everyday usage. Even among experts and in textbooks, weight is ambiguously defined as either the gravitational force on an object or operationally as the magnitude of the force an object exerts on a measuring scale. This poses both conceptual and language difficulties…

  3. Chasing Ambiguity: Critical Reflections on Working with Dance Graduates

    Science.gov (United States)

    Roe, Sarah

    2017-01-01

    This paper questions whether are we able to foster uncertainty and ambiguity within higher education arts programmes, specifically alongside current institutional demands and embedded pedagogies. If not, then what effect does this have on current dance graduates? I attend to these questions through critical reflections upon my work as a pedagogue,…

  4. The processing of lexical ambiguity in healthy ageing and Parkinson׳s disease: role of cortico-subcortical networks.

    Science.gov (United States)

    Ketteler, Simon; Ketteler, Daniel; Vohn, René; Kastrau, Frank; Schulz, Jörg B; Reetz, Kathrin; Huber, Walter

    2014-09-18

    Previous neuroimaging studies showed that correct resolution of lexical ambiguity relies on the integrity of prefrontal and inferior parietal cortices. Whereas prefrontal brain areas were associated with executive control over semantic selection, inferior parietal areas were linked with access to modality-independent representations of semantic memory. Yet insufficiently understood is the contribution of subcortical structures in ambiguity processing. Patients with disturbed basal ganglia function such as Parkinson׳s disease (PD) showed development of discourse comprehension deficits evoked by lexical ambiguity. To further investigate the engagement of cortico-subcortical networks functional Magnetic Resonance Imaging (fMRI) was monitored during ambiguity resolution in eight early PD patients without dementia and 14 age- and education-matched controls. Participants were required to relate meanings to a lexically ambiguous target (homonym). Each stimulus consisted of two words arranged on top of a screen, which had to be attributed to a homonym at the bottom. Brain activity was found in bilateral inferior parietal (BA 39), right middle temporal (BA 21/22), left middle frontal (BA 10) and bilateral inferior frontal areas (BA 45/46). Extent and amplitude of activity in the angular gyrus changed depending on semantic association strength that varied between conditions. Less activity in the left caudate was associated with semantic integration deficits in PD. The results of the present study suggest a relationship between subtle language deficits and early stages of basal ganglia dysfunction. Uncovering impairments in ambiguity resolution may be of future use in the neuropsychological assessment of non-motor deficits in PD. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. "The impact of uncertain threat on affective bias: Individual differences in response to ambiguity": Correction.

    Science.gov (United States)

    2018-04-01

    Reports an error in "The impact of uncertain threat on affective bias: Individual differences in response to ambiguity" by Maital Neta, Julie Cantelon, Zachary Haga, Caroline R. Mahoney, Holly A. Taylor and F. Caroline Davis ( Emotion , 2017[Dec], Vol 17[8], 1137-1143). In this article, the copyright attribution was incorrectly listed under the Creative Commons CC-BY license due to production-related error. The correct copyright should be "In the public domain." The online version of this article has been corrected. (The following abstract of the original article appeared in record 2017-40275-001.) Individuals who operate under highly stressful conditions (e.g., military personnel and first responders) are often faced with the challenge of quickly interpreting ambiguous information in uncertain and threatening environments. When faced with ambiguity, it is likely adaptive to view potentially dangerous stimuli as threatening until contextual information proves otherwise. One laboratory-based paradigm that can be used to simulate uncertain threat is known as threat of shock (TOS), in which participants are told that they might receive mild but unpredictable electric shocks while performing an unrelated task. The uncertainty associated with this potential threat induces a state of emotional arousal that is not overwhelmingly stressful, but has widespread-both adaptive and maladaptive-effects on cognitive and affective function. For example, TOS is thought to enhance aversive processing and abolish positivity bias. Importantly, in certain situations (e.g., when walking home alone at night), this anxiety can promote an adaptive state of heightened vigilance and defense mobilization. In the present study, we used TOS to examine the effects of uncertain threat on valence bias, or the tendency to interpret ambiguous social cues as positive or negative. As predicted, we found that heightened emotional arousal elicited by TOS was associated with an increased tendency to

  6. Top-down influences on ambiguous perception: the role of stable and transient states of the observer

    Science.gov (United States)

    Scocchia, Lisa; Valsecchi, Matteo; Triesch, Jochen

    2014-01-01

    The world as it appears to the viewer is the result of a complex process of inference performed by the brain. The validity of this apparently counter-intuitive assertion becomes evident whenever we face noisy, feeble or ambiguous visual stimulation: in these conditions, the state of the observer may play a decisive role in determining what is currently perceived. On this background, ambiguous perception and its amenability to top-down influences can be employed as an empirical paradigm to explore the principles of perception. Here we offer an overview of both classical and recent contributions on how stable and transient states of the observer can impact ambiguous perception. As to the influence of the stable states of the observer, we show that what is currently perceived can be influenced (1) by cognitive and affective aspects, such as meaning, prior knowledge, motivation, and emotional content and (2) by individual differences, such as gender, handedness, genetic inheritance, clinical conditions, and personality traits and by (3) learning and conditioning. As to the impact of transient states of the observer, we outline the effects of (4) attention and (5) voluntary control, which have attracted much empirical work along the history of ambiguous perception. In the huge literature on the topic we trace a difference between the observer's ability to control dominance (i.e., the maintenance of a specific percept in visual awareness) and reversal rate (i.e., the switching between two alternative percepts). Other transient states of the observer that have more recently drawn researchers' attention regard (6) the effects of imagery and visual working memory. (7) Furthermore, we describe the transient effects of prior history of perceptual dominance. (8) Finally, we address the currently available computational models of ambiguous perception and how they can take into account the crucial share played by the state of the observer in perceiving ambiguous displays. PMID

  7. Pragmatic Failure and Referential Ambiguity when Attorneys Ask Child Witnesses “Do You Know/Remember” Questions

    Science.gov (United States)

    Evans, Angela D.; Stolzenberg, Stacia N.; Lyon, Thomas D.

    2016-01-01

    “Do you know” and “Do you remember” (DYK/R) questions explicitly ask whether one knows or remembers some information while implicitly asking for that information. This study examined how 104 4- to 9-year-old children testifying in child sexual abuse cases responded to DYK/R wh- and yes/no questions. When asked DYK/R questions containing an implicit wh- question requesting information, children often provided unelaborated “Yes” responses. Attorneys’ follow-up questions suggested that children usually misunderstood the pragmatics of the questions. When DYK/R questions contained an implicit yes/no question, unelaborated “Yes” or “No” responses could be responding to the explicit or the implicit questions resulting in referentially ambiguous responses. Children often provided referentially ambiguous responses and attorneys usually failed to disambiguate children’s answers. Although pragmatic failure following DYK/R wh- questions decreased with age, the likelihood of referential ambiguity following DYK/R yes/no questions did not. The results highlight the risks of serious miscommunications caused by pragmatic misunderstanding and referential ambiguity when children testify. PMID:28652686

  8. Ambiguity towards Multiple Historical Performance Information Signals: Evidence from Indonesian Open-Ended Mutual Fund Investors

    Directory of Open Access Journals (Sweden)

    Haris Pratama Loeis

    2015-10-01

    Full Text Available This study focuses on the behavior of open-ended mutual fund investors when encountered with multiple information signals of mutual fund’s historical performance. The behavior of investors can be reflected on their decision to subscribe or redeem their funds from mutual funds. Moreover, we observe the presence of ambiguity within investors due to multiple information signals, and also their reaction towards it. Our finding shows that open-ended mutual fund investors do not only have sensitivity towards past performance information signals, but also have additional sensitivity towards the ambiguity of multiple information signals. Because of the presence of ambiguity, investors give more consideration to negative information signals and the worst information signal in their investment decisions. Normal 0 false false false EN-US X-NONE X-NONE

  9. Rotation Matrix Method Based on Ambiguity Function for GNSS Attitude Determination.

    Science.gov (United States)

    Yang, Yingdong; Mao, Xuchu; Tian, Weifeng

    2016-06-08

    Global navigation satellite systems (GNSS) are well suited for attitude determination. In this study, we use the rotation matrix method to resolve the attitude angle. This method achieves better performance in reducing computational complexity and selecting satellites. The condition of the baseline length is combined with the ambiguity function method (AFM) to search for integer ambiguity, and it is validated in reducing the span of candidates. The noise error is always the key factor to the success rate. It is closely related to the satellite geometry model. In contrast to the AFM, the LAMBDA (Least-squares AMBiguity Decorrelation Adjustment) method gets better results in solving the relationship of the geometric model and the noise error. Although the AFM is more flexible, it is lack of analysis on this aspect. In this study, the influence of the satellite geometry model on the success rate is analyzed in detail. The computation error and the noise error are effectively treated. Not only is the flexibility of the AFM inherited, but the success rate is also increased. An experiment is conducted in a selected campus, and the performance is proved to be effective. Our results are based on simulated and real-time GNSS data and are applied on single-frequency processing, which is known as one of the challenging case of GNSS attitude determination.

  10. Rotation Matrix Method Based on Ambiguity Function for GNSS Attitude Determination

    Directory of Open Access Journals (Sweden)

    Yingdong Yang

    2016-06-01

    Full Text Available Global navigation satellite systems (GNSS are well suited for attitude determination. In this study, we use the rotation matrix method to resolve the attitude angle. This method achieves better performance in reducing computational complexity and selecting satellites. The condition of the baseline length is combined with the ambiguity function method (AFM to search for integer ambiguity, and it is validated in reducing the span of candidates. The noise error is always the key factor to the success rate. It is closely related to the satellite geometry model. In contrast to the AFM, the LAMBDA (Least-squares AMBiguity Decorrelation Adjustment method gets better results in solving the relationship of the geometric model and the noise error. Although the AFM is more flexible, it is lack of analysis on this aspect. In this study, the influence of the satellite geometry model on the success rate is analyzed in detail. The computation error and the noise error are effectively treated. Not only is the flexibility of the AFM inherited, but the success rate is also increased. An experiment is conducted in a selected campus, and the performance is proved to be effective. Our results are based on simulated and real-time GNSS data and are applied on single-frequency processing, which is known as one of the challenging case of GNSS attitude determination.

  11. Preregularization and the structure of loop-momentum ambiguities within quantum corrections to the supercurrent

    International Nuclear Information System (INIS)

    Chowdhury, A.M.; Elias, V.; McKeon, D.G.C.; Mann, R.B.

    1986-01-01

    The anomaly in the supercurrent amplitude S/sub μ//sub ν/ is analyzed to one-loop order for N = 1 supersymmetry in the Wess-Zumino gauge within the framework of preregularization, in which loop-momentum-routing ambiguities percolate into shift-of-integration-variable surface terms peculiar to exactly four space-time dimensions. We find the supercurrent anomaly to be a consequence of the inability of such ambiguities (within a demonstrably finite set of quantum corrections) to absorb violations of gauge invariance (q/sup ν/S/sub μ//sub ν/not =0) and supersymmetry (partial/sup μ/S/sub μ//sub ν/equivalentpartialxSnot =0) simultaneously, a feature quite similar to the inability of VVA-triangle ambiguities to absorb violations of gauge invariance and the axial-vector-current Ward identity simultaneously. We also find that if gauge invariance is preserved, the contribution to the supercurrent anomaly obtained from O(g 2 ) quantum corrections to the supercurrent involves no infrared or ultraviolet infinities and resides in partialxS rather than γxS. This last result is a consequence of maintaining exactly four space-time dimensions, as is necessary for momentum-routing ambiguities to appear at all in the quantum corrections. The connection between our results and similar results obtained from an Adler-Rosenberg symmetry argument is examined in detail

  12. Length Matters: Informational Load in Ambiguity Resolution

    Directory of Open Access Journals (Sweden)

    Barbara Hemforth

    2013-07-01

    Full Text Available In this paper, we will compare prosodic and pragmatic approaches to the role of constituent length in attachment ambiguities. Lengthening a constituent affects its informativity: longer constituents are usually less predictable (Levy & Florian, 2007 and demand a higher processing load than shorter ones (Almor, 1999. Following neo-Gricean accounts (Levinson, 1987 and 1991, increased informational load needs to be justified. This justification is achieved more easily when the long constituent conveys new information and when it relates to central elements of the utterance. Informational load is, however, not a simple question of length in numbers of characters or syllables but more likely a question of amount of information. In three off-line experiments using a cloze task, we will compare the effect of lengthening ambiguous prepositional phrases as in [1a/b/c] either by lengthening a city name or by adding information about the city. We will show that only lengthening by adding information increases attachment to a more central element of the utterance. These results will be discussed based on prosodic and pragmatic factors explaining the role of constituent length for attachment ambiguities.[1] Peter met the doctor of the lawyer from a. Apt. / b. Aix-en-Provence / c. the beautiful city of Apt.Dans cet article, nous comparons une approche prosodique avec une approche pragmatique pour rendre compte des effets de la longueur des constituants dans les ambigüités d’attachement. Augmenter la longueur d’un constituant a des conséquences sur l’information qu’il véhicule : plus un constituant est long et moins il est prédictible (Levy et Florian, 2007 et plus son coût de traitement augmente (Almor, 1999. Suivant les principes néo-gricéens (Levinson, 1987 et 1991, augmenter le poids informationnel doit être justifié. Cette justification est plus facilement satisfaite lorsqu’un constituant long véhicule une information

  13. Subsequent to suppression: Downstream comprehension consequences of noun/verb ambiguity in natural reading

    Science.gov (United States)

    Stites, Mallory C.; Federmeier, Kara D.

    2015-01-01

    We used eye-tracking to investigate the downstream processing consequences of encountering noun/verb (NV) homographs (i.e., park) in semantically neutral but syntactically constraining contexts. Target words were followed by a prepositional phrase containing a noun that was plausible for only one meaning of the homograph. Replicating previous work, we found increased first fixation durations on NV homographs compared to unambiguous words, which persisted into the next sentence region. At the downstream noun, we found plausibility effects following ambiguous words that were correlated with the size of a reader's first fixation effect, suggesting that this effect reflects the recruitment of processing resources necessary to suppress the homograph's context-inappropriate meaning. Using these same stimuli, Lee and Federmeier (2012) found a sustained frontal negativity to the NV homographs, and, on the downstream noun, found a plausibility effect that was also positively correlated with the size of a reader's ambiguity effect. Together, these findings suggest that when only syntactic constraints are available, meaning selection recruits inhibitory mechanisms that can be measured in both first fixation slowdown and ERP ambiguity effects. PMID:25961358

  14. [Eye movement parameters in reading the sentences with syntactic ambiguity in Russian language].

    Science.gov (United States)

    Anisimov, V A; Fedorova, O V; Latanov, A V

    2014-01-01

    We studied the eye movement parameters during reading of syntactically ambiguous sentences with feminine relative clause in Russian language. A priori difficulties of sentence structural analysis results in increase of time spent on reading as opposed to reading control sentences (unambiguous). Such a delay is caused by an increase of frequency of regressions (backward saccades) which are executed for rereading an ambiguous fragment ofsentence. This fact in turn leads to an increase in number of fixations and their duration. The total reading time for particular words composing the ambiguous fragment of sentence depended on disambiguation result (relative clause attachment, early/late closure). In case of early closure (when the subject attached relative clause to first noun) the total reading time for this noun exceeded one for second noun. In case of late closure (when the subject attached relative clause to second noun) the total reading time for both nouns didn't differ. Our results indicate that early closure domination in Russian language determines the greater total reading time for first noun of nominal group associated with relative clause.

  15. Radiological Evaluation of Ambiguous Genitalia with Various Imaging Modalities

    Science.gov (United States)

    Ravi, N.; Bindushree, Kadakola

    2012-07-01

    Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. These can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management. We describe case series on ambiguous genitalia presented to our department who were evaluated with multiple imaging modalities.

  16. Determination of Patterson group symmetry from sparse multi-crystal data sets in the presence of an indexing ambiguity.

    Science.gov (United States)

    Gildea, Richard J; Winter, Graeme

    2018-05-01

    Combining X-ray diffraction data from multiple samples requires determination of the symmetry and resolution of any indexing ambiguity. For the partial data sets typical of in situ room-temperature experiments, determination of the correct symmetry is often not straightforward. The potential for indexing ambiguity in polar space groups is also an issue, although methods to resolve this are available if the true symmetry is known. Here, a method is presented to simultaneously resolve the determination of the Patterson symmetry and the indexing ambiguity for partial data sets. open access.

  17. Questions of quark confinement and ambiguities in Coulomb gauge of Yang-Mills fields

    International Nuclear Information System (INIS)

    Abarbanel, H.D.I.; Bartels, J.

    1978-01-01

    The ambiguities considered by Gribov in the formulation of Coulomb gauge in non-Abelian gauge theories are discussed and the division of gauge field space into a sector with a unique transverse gauge, a sector with a two-fold ambiguity in transverse gauge, etc. is reviewed. The authors argue in a semi-classical fashion that transitions between these sectors readily occur and discuss the connection with ideas of quark confinement in Coulomb gauge. Because of these transitions it appears that the functional integral formulation of Coulomb gauge will be rather more complicated than expected in the past. (Auth.)

  18. Correlations of self-esteem and intolerance of ambiguity with risk aversion.

    Science.gov (United States)

    Johanson, J C

    2000-10-01

    The current paper reports for 80 undergraduates that risk aversion is greater among those with lower self-esteem scores on Rosenberg's Self-esteem Scale and those with higher scores on Budner's Intolerance of Ambiguity Scale.

  19. On the elimination of infinitesimal Gribov ambiguities in non-Abelian gauge theories

    International Nuclear Information System (INIS)

    Pereira, Antonio D.; Sobreiro, Rodrigo F.

    2013-01-01

    An alternative method to account for the Gribov ambiguities in gauge theories is presented. It is shown that, to eliminate Gribov ambiguities, at infinitesimal level, it is required to break the BRST symmetry in a soft manner. This can be done by introducing a suitable extra constraint that eliminates the infinitesimal Gribov copies. It is shown that the present approach is consistent with the well established known cases in the literature, i.e., the Landau and maximal Abelian gauges. The method is valid for gauges depending exclusively on the gauge field and is restricted to classical level. However, occasionally, we deal with quantum aspects of the technique, which are used to improve the results. (orig.)

  20. Finding Home: Landmark Ambiguity in Human Navigation

    Directory of Open Access Journals (Sweden)

    Simon Jetzschke

    2017-07-01

    Full Text Available Memories of places often include landmark cues, i.e., information provided by the spatial arrangement of distinct objects with respect to the target location. To study how humans combine landmark information for navigation, we conducted two experiments: To this end, participants were either provided with auditory landmarks while walking in a large sports hall or with visual landmarks while walking on a virtual-reality treadmill setup. We found that participants cannot reliably locate their home position due to ambiguities in the spatial arrangement when only one or two uniform landmarks provide cues with respect to the target. With three visual landmarks that look alike, the task is solved without ambiguity, while audio landmarks need to play three unique sounds for a similar performance. This reduction in ambiguity through integration of landmark information from 1, 2, and 3 landmarks is well modeled using a probabilistic approach based on maximum likelihood estimation. Unlike any deterministic model of human navigation (based e.g., on distance or angle information, this probabilistic model predicted both the precision and accuracy of the human homing performance. To further examine how landmark cues are integrated we introduced systematic conflicts in the visual landmark configuration between training of the home position and tests of the homing performance. The participants integrated the spatial information from each landmark near-optimally to reduce spatial variability. When the conflict becomes big, this integration breaks down and precision is sacrificed for accuracy. That is, participants return again closer to the home position, because they start ignoring the deviant third landmark. Relying on two instead of three landmarks, however, goes along with responses that are scattered over a larger area, thus leading to higher variability. To model the breakdown of integration with increasing conflict, the probabilistic model based on a

  1. Measurement of sin2β in Tree Dominated B0 Decays and Ambiguity Removal

    International Nuclear Information System (INIS)

    Lacker, H.

    2007-01-01

    The most recent results from the B-factories on the time-dependent CP asymmetries measured in B 0 -decays mediated by b→cc-bar s quark-transitions are reviewed. The Standard Model interpretation of the results in terms of the parameter sin2β leads to a four-fold ambiguity on the unitarity triangle β which can be reduced to a two-fold ambiguity by measuring the sign of the parameter cos2β. The results on cos2β obtained so far are reviewed

  2. Decision making under ambiguity and under risk in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Delazer, Margarete; Zamarian, Laura; Bonatti, Elisabeth; Kuchukhidze, Giorgi; Koppelstätter, Florian; Bodner, Thomas; Benke, Thomas; Trinka, Eugen

    2010-01-01

    Decision making is essential in everyday life. Though the importance of the mesial temporal lobe in emotional processing and feedback learning is generally recognized, decision making in mesial temporal lobe epilepsy (mTLE) is almost unexplored so far. Twenty-eight consecutive epilepsy patients with drug resistant mTLE and fifty healthy controls performed decision tasks under initial ambiguity (participants have to learn by feedback to make advantageous decisions) and under risk (advantageous choices may be made by estimating risks and by rational strategies). A subgroup analysis compared the performance of patients affected by MRI-verified abnormalities of the hippocampus or amygdala. The effect of lesion side was also assessed. In decision under ambiguity, mTLE patients showed marked deficits and did not improve over the task. Patients with hippocampus abnormality and patients with amygdala abnormality showed comparable deficits. No difference was found between right and left TLE groups. In decision under risk, mTLE patients performed at the same level as controls. Results suggest that mTLE patients have difficulties in learning from feedback and in making decisions in uncertain, ambiguous situations. By contrast, they are able to make advantageous decisions when full information is given and risks, possible gains and losses are exactly defined.

  3. Phonological Iconicity electrifies: An ERP study on affective sound-to-meaning correspondences in German

    Directory of Open Access Journals (Sweden)

    Susann Ullrich

    2016-08-01

    Full Text Available While linguistic theory posits an arbitrary relation between signifiers and the signified (de Saussure, 1916, our analysis of a large-scale German database containing affective ratings of words revealed that certain phoneme clusters occur more often in words denoting concepts with negative and arousing meaning. Here, we investigate how such phoneme clusters that potentially serve as sublexical markers of affect can influence language processing. We registered the EEG signal during a lexical decision task with a novel manipulation of the words’ putative sublexical affective potential: the means of valence and arousal values for single phoneme clusters, each computed as a function of respective values of words from the database these phoneme clusters occur in. Our experimental manipulations also investigate potential contributions of formal salience to the sublexical affective potential: Typically, negative high-arousing phonological segments—based on our calculations—tend to be less frequent and more structurally complex than neutral ones. We thus constructed two experimental sets, one involving this natural confound, while controlling for it in the other. A negative high-arousing sublexical affective potential in the strictly controlled stimulus set yielded an early posterior negativity (EPN, in similar ways as an independent manipulation of lexical affective content. When other potentially salient formal features at the sublexical level were not controlled for, the effect of the sublexical affective potential was strengthened and prolonged (250-650 ms, presumably because formal salience helps making specific phoneme clusters efficient sublexical markers of negative high-arousing affective meaning. These neurophysiological data support the assumption that the organization of a language´s vocabulary involves systematic sound-to-meaning correspondences at the phonemic level that influence the way we process language.

  4. Context-dependent lexical ambiguity resolution: MEG evidence for the time-course of activity in left inferior frontal gyrus and posterior middle temporal gyrus.

    Science.gov (United States)

    Mollo, Giovanna; Jefferies, Elizabeth; Cornelissen, Piers; Gennari, Silvia P

    An MEG study investigated the role of context in semantic interpretation by examining the comprehension of ambiguous words in contexts leading to different interpretations. We compared high-ambiguity words in minimally different contexts (to bowl, the bowl) to low-ambiguity counterparts (the tray, to flog). Whole brain beamforming revealed the engagement of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (LPMTG). Points of interest analyses showed that both these sites showed a stronger response to verb-contexts by 200 ms post-stimulus and displayed overlapping ambiguity effects that were sustained from 300 ms onwards. The effect of context was stronger for high-ambiguity words than for low-ambiguity words at several different time points, including within the first 100 ms post-stimulus. Unlike LIFG, LPMTG also showed stronger responses to verb than noun contexts in low-ambiguity trials. We argue that different functional roles previously attributed to LIFG and LPMTG are in fact played out at different periods during processing. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  5. Interpretation of ambiguities by schoolchildren with low birth weight from Embu das Artes, São Paulo state, Brazil.

    Science.gov (United States)

    Pessoa, Rebeca Rodrigues; Araújo, Sarah Cueva Cândido Soares de; Isotani, Selma Mie; Puccini, Rosana Fiorini; Perissinoto, Jacy

    To assess the development of language regarding the ability to recognize and interpret lexical ambiguity in low-birth-weight schoolchildren enrolled at the school system in the municipality of Embu das Artes, Sao Paulo state, compared with that of schoolchildren with normal birth weight. A case-control, retrospective, cross-sectional study conducted with 378 schoolchildren, both genders, aged 5 to 9.9 years, from the municipal schools of Embu das Artes. Study Group (SG) comprising 210 schoolchildren with birth weight Control Group (CG) composed of 168 school children with birth weight ≥ 2500 g. Participants of both groups were compared with respect to the skills of recognition and verbal interpretation of sentences containing lexical ambiguity using the Test of Language Competence. Variables of interest: Age and gender of children; age and schooling of mothers. Statistical analysis: Descriptive analysis to characterize the sample and score per group; Student's t test for comparison between the total scores of each skill/subtest; Chi-square test to compare items within each subtest; multiple regression analysis for the intervening variables. Participants of the SG presented lower scores for ambiguous sentences compared with those of participants of the CG. Multiple regression analysis showed that child's current age was a predictor for all metalinguistic skills regarding interpretation of ambiguities in both groups. Participants of the SG presented lower specific and total scores than those of participants of the CG for ambiguity skills. The child's current age factor positively influenced the ambiguity skills in both groups.

  6. Psychometric Analysis of Role Conflict and Ambiguity Scales in Academia

    Science.gov (United States)

    Khan, Anwar; Yusoff, Rosman Bin Md.; Khan, Muhammad Muddassar; Yasir, Muhammad; Khan, Faisal

    2014-01-01

    A comprehensive Psychometric Analysis of Rizzo et al.'s (1970) Role Conflict & Ambiguity (RCA) scales were performed after its distribution among 600 academic staff working in six universities of Pakistan. The reliability analysis includes calculation of Cronbach Alpha Coefficients and Inter-Items statistics, whereas validity was determined by…

  7. A Mindfulness Experiential Small Group to Help Students Tolerate Ambiguity

    Science.gov (United States)

    Bohecker, Lynn; Vereen, Linwood G.; Wells, Pamela C.; Wathen, Cristen C.

    2016-01-01

    This study explored the lived experiences of 20 counselors-in-training (CITs) in a mindfulness experiential small group. Using grounded theory, the authors described a 5-dimensional model for navigating ambiguity. Findings suggest mindfulness training provides CITs self-reflection skills and a greater ability to manage cognitive complexity.

  8. An Introduction to the Ambiguity Tolerance: As a Source of Variation in English-Persian Translation

    Directory of Open Access Journals (Sweden)

    Hooshang Khoshsima

    2017-05-01

    Full Text Available Different individuals provide different translations of different qualities of the same text. This may be due to one’s dominant cognitive style and individuals’ particular personal characteristics (Khoshsima & Hashemi Toroujeni, 2017 in general or ambiguity tolerance in particular. A certain degree of ambiguity tolerance (henceforth AI has been found to facilitate language learning (Chapelle, 1983; Ehrman, 1999; Ely, 1995. However, this influential factor has been largely overlooked in translation studies. The purpose of this study was to find the relationship between AT and translation quality by identifying the expected positive correlation between the level of AT and the numbers of translation errors. Out of the 56 undergraduates of English-Persian Translation at Chabahar Maritime University (CMU, a sample of 34 top students was selected based on their scores on the reading comprehension which enjoys a special focus in many contexts (Khoshsima & Rezaeian Tiyar, 2014 and structure subtests of the TOEFL. The participants responded to the SLTAS questionnaire for AT developed by Ely (1995. The questionnaire had a high alpha internal consistency reliability of .84 and standardized item alpha of .84. In the next stage of the research, the participants translated a short passage of contemporary English into Persian, which was assessed using the SICAL III scale for TQA developed and used by Canadian Government’s Translation Bureau as its official TQA model (Williams, 1989.  Then, to find the relationship between the level of ambiguity tolerance in undergraduates of English-Persian translation at Chabahar Maritime University and their translation quality, analysis of the collected data revealed a significant positive correlation (r=440, p<.05 between the participants’ degree of AT and the numbers of errors in their translations. Controlling for SL proficiency, the correlation was still significantly positive (r=.397, p<.05. Accordingly, it

  9. Conservation′s Ambiguities: Rangers on the Periphery of the W Park, Burkina Faso

    Directory of Open Access Journals (Sweden)

    Julie Poppe

    2012-01-01

    Full Text Available This article demonstrates the central role of ambiguity in the (reproduction process of conservation practice. It argues that some current political economy as well as environmentality approaches to research conservation practice fail to capture the complexity of the lived experience of local conservationists. The article focuses on the multiple identities of rangers in interaction with other residents at the periphery of the W Park in Burkina Faso, as rangers are local conservationists who simultaneously submit to and produce conservation practices. Park rangers are village men who are recruited under the banner of community participation in conservation projects and state forestry. On a day-to-day basis, these rangers help the foresters with the management of the natural resources on the one hand, and guide tourists, especially in the hunting concessions, on the other. They occupy ambiguous positions at the crossroads of conservationist, state, political, economic, spiritual, social, and cultural practices, inherent to their conservation occupations at the lowest echelon, where residents have to transform conservation policies into practices. It is precisely this ambiguity that turns out to ensure the conservation implementation.

  10. Completing the surrogate motherhood process: parental order reporters' attitudes towards surrogacy arrangements, role ambiguity and role conflict.

    Science.gov (United States)

    Purewal, Satvinder; Crawshaw, Marilyn; van den Akker, Olga

    2012-06-01

    This study investigated the attitudes of parental order reporters (PORs) towards their work with surrogacy arrangements and their experiences of role conflict and role ambiguity. A questionnaire was used to assess PORs' perceptions of their role in parental order [PO] applications, attitudes towards surrogacy arrangements and the legal process and the influence of role ambiguity or conflict. Questionnaires were distributed to all PORs employed by the Children and Family Court Advisory and Support Service in England. Thirty-three PORs participated (response rate 46%) who, on average, had each completed five PO applications (range 1-40). Positive attitudes towards surrogacy and the child's needs for openness about origins were found. Concerns about the inadequacy of preparation and assessment arrangements, overseas arrangements and non-regulation of surrogacy agencies were evident. PORs with high-role ambiguity were more likely to report less positive attitudes towards the emotional consequence of surrogacy on offspring. High scores on role ambiguity and role conflict were reflected in less positive attitudes towards the parties' preparation towards parenthood. These results have implications for training, policy and practice in this area.

  11. Action-angle variables for the harmonic oscillator : ambiguity spin x duplication spin

    International Nuclear Information System (INIS)

    Oliveira, C.R. de; Malta, C.P.

    1983-08-01

    The difficulties of obtaining for the harmonic oscillator a well defined unitary transformation to action-angle variables were overcome by M. Moshinsky and T.H. Seligman through the introduction of a spinlike variable (ambiguity spin) from a classical point of view. The difficulty of defining a unitary phase operator for the harmonic oscillator was overcome by Roger G. Newton also through the introduction of a spinlike variable (named duplication spin by us) but within a quantum framework. The relation between the ambiguity spin and the duplication spin by introducing these two types of spins in the canonical transformation to action-angle variables is investigated. Doing this it is possible to obtain both well defined unitary transformation and phase operator. (Author) [pt

  12. On the Measurement and Properties of Ambiguity in Probabilistic Expectations

    Science.gov (United States)

    Pickett, Justin T.; Loughran, Thomas A.; Bushway, Shawn

    2015-01-01

    Survey respondents' probabilistic expectations are now widely used in many fields to study risk perceptions, decision-making processes, and behavior. Researchers have developed several methods to account for the fact that the probability of an event may be more ambiguous for some respondents than others, but few prior studies have empirically…

  13. Ambiguity resolving based on cosine property of phase differences for 3D source localization with uniform circular array

    Science.gov (United States)

    Chen, Xin; Wang, Shuhong; Liu, Zhen; Wei, Xizhang

    2017-07-01

    Localization of a source whose half-wavelength is smaller than the array aperture would suffer from serious phase ambiguity problem, which also appears in recently proposed phase-based algorithms. In this paper, by using the centro-symmetry of fixed uniform circular array (UCA) with even number of sensors, the source's angles and range can be decoupled and a novel ambiguity resolving approach is addressed for phase-based algorithms of source's 3-D localization (azimuth angle, elevation angle, and range). In the proposed method, by using the cosine property of unambiguous phase differences, ambiguity searching and actual-value matching are first employed to obtain actual phase differences and corresponding source's angles. Then, the unambiguous angles are utilized to estimate the source's range based on a one dimension multiple signal classification (1-D MUSIC) estimator. Finally, simulation experiments investigate the influence of step size in search and SNR on performance of ambiguity resolution and demonstrate the satisfactory estimation performance of the proposed method.

  14. Reading Comprehension and Tolerance against Comprehension Ambiguities: An Empirical Study of Iranian GFL-Learners in Communicative Education

    Science.gov (United States)

    Haghani, Nader; Bahmannejad, Fereshteh

    2018-01-01

    The present study examines the influence of ambiguity tolerance on the performance of Iranian GFL-learners (Note 1) at level B1 in the processing of gap-filling-text tests. It is assumed that learners with more tolerance of ambiguity achieve better results in the reading comprehension or in the contextual guessing of the omitted words. 34 GFL…

  15. Four-dimensional aether-like Lorentz-breaking QED revisited and problem of ambiguities

    Energy Technology Data Exchange (ETDEWEB)

    Baeta Scarpelli, A.P. [Setor Tecnico-Cientifico, Departamento de Policia Federal, Rua Hugo D' Antola, 95, Lapa, Sao Paulo (Brazil); Mariz, T. [Universidade Federal de Alagoas, Instituto de Fisica, Maceio, Alagoas (Brazil); Nascimento, J.R.; Petrov, A.Yu. [Universidade Federal da Paraiba, Departamento de Fisica, Caixa Postal 5008, Joao Pessoa, Paraiba (Brazil)

    2013-08-15

    In this paper, we consider the perturbative generation of the CPT-even aether-like Lorentz-breaking term in the extended Lorentz-breaking QED within different approaches and discuss its ambiguities. (orig.)

  16. Four-dimensional aether-like Lorentz-breaking QED revisited and problem of ambiguities

    International Nuclear Information System (INIS)

    Baeta Scarpelli, A.P.; Mariz, T.; Nascimento, J.R.; Petrov, A.Yu.

    2013-01-01

    In this paper, we consider the perturbative generation of the CPT-even aether-like Lorentz-breaking term in the extended Lorentz-breaking QED within different approaches and discuss its ambiguities. (orig.)

  17. Performance analysis of PPP ambiguity resolution with UPD products estimated from different scales of reference station networks

    Science.gov (United States)

    Wang, Siyao; Li, Bofeng; Li, Xingxing; Zang, Nan

    2018-01-01

    Integer ambiguity fixing with uncalibrated phase delay (UPD) products can significantly shorten the initialization time and improve the accuracy of precise point positioning (PPP). Since the tracking arcs of satellites and the behavior of atmospheric biases can be very different for the reference networks with different scales, the qualities of corresponding UPD products may be also various. The purpose of this paper is to comparatively investigate the influence of different scales of reference station networks on UPD estimation and user ambiguity resolution. Three reference station networks with global, wide-area and local scales are used to compute the UPD products and analyze their impact on the PPP-AR. The time-to-first-fix, the unfix rate and the incorrect fix rate of PPP-AR are analyzed. Moreover, in order to further shorten the convergence time for obtaining precise positioning, a modified partial ambiguity resolution (PAR) and corresponding validation strategy are presented. In this PAR method, the ambiguity subset is determined by removing the ambiguity one by one in the order of ascending elevations. Besides, for static positioning mode, a coordinate validation strategy is employed to enhance the reliability of the fixed coordinate. The experiment results show that UPD products computed by smaller station network are more accurate and lead to a better coordinate solution; the PAR method used in this paper can shorten the convergence time and the coordinate validation strategy can improve the availability of high precision positioning.

  18. A Review of the Scattering-Parameter Extraction Method with Clarification of Ambiguity Issues in Relation to Metamaterial Homogenization

    DEFF Research Database (Denmark)

    Arslanagic, Samel; Hansen, Troels Vejle; Mortensen, N. Asger

    2013-01-01

    The scattering-parameter extraction method of metamaterial homogenization is reviewed to show that the only ambiguity is that related to the choice of the branch of the complex logarithmic function (or the complex inverse cosine function). It is shown that the method has no ambiguity for the sign...

  19. Why Ambiguity Detection Is a Predictor of Early Reading Skill

    Science.gov (United States)

    Wankoff, Lorain Szabo; Cairns, Helen Smith

    2009-01-01

    This study was designed to determine the contributions of metalinguistic skill and psycholinguistic processing ability to children's ability to detect the ambiguity of sentences and the relationship among all three factors to early reading ability. A total of 20 first graders and 20 second graders were given tasks testing the following abilities:…

  20. The human amygdala parametrically encodes the intensity of specific facial emotions and their categorical ambiguity

    Science.gov (United States)

    Wang, Shuo; Yu, Rongjun; Tyszka, J. Michael; Zhen, Shanshan; Kovach, Christopher; Sun, Sai; Huang, Yi; Hurlemann, Rene; Ross, Ian B.; Chung, Jeffrey M.; Mamelak, Adam N.; Adolphs, Ralph; Rutishauser, Ueli

    2017-01-01

    The human amygdala is a key structure for processing emotional facial expressions, but it remains unclear what aspects of emotion are processed. We investigated this question with three different approaches: behavioural analysis of 3 amygdala lesion patients, neuroimaging of 19 healthy adults, and single-neuron recordings in 9 neurosurgical patients. The lesion patients showed a shift in behavioural sensitivity to fear, and amygdala BOLD responses were modulated by both fear and emotion ambiguity (the uncertainty that a facial expression is categorized as fearful or happy). We found two populations of neurons, one whose response correlated with increasing degree of fear, or happiness, and a second whose response primarily decreased as a linear function of emotion ambiguity. Together, our results indicate that the human amygdala processes both the degree of emotion in facial expressions and the categorical ambiguity of the emotion shown and that these two aspects of amygdala processing can be most clearly distinguished at the level of single neurons. PMID:28429707