915 resultados para Respondent Uncertainty


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Many mental disorders are characterised by the presence of compulsions and incontrollable habits. Most studies on habit learning, both in animals and in humans, are based on positive reinforcement paradigms. However, the compulsions and habits involved in some mental disorders may be better understood as avoidance behaviours, which involve some peculiarities, such as anxiety states, that have been shown to promote habitual responses. Consequently, we studied habit acquisition by using a free-operant discriminated avoidance procedure. Furthermore, we checked whether intolerance of uncertainty could predispose to avoidance habit acquisition. Participants learned to avoid an aversive noise presented either to the right or to the left ear by pressing two different keys. After a devaluation phase where the volume of the noise presented to one of the ears was reduced, participants went through a test phase identical to the avoidance learning phase except for the fact that the noise was never administered. Habit acquisition was inferred by comparing the rate of responses to the stimulus signalling the devalued reinforcer and to the stimulus signalling the non-devalued reinforcer. The results showed that intolerance of uncertainty was related to the absence of differences between the referred conditions, which entail avoidance habit acquisition.

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Objective Transparent evidence-based decision making has been promoted worldwide to engender trust in science and policy making. Yet, little attention has been given to transparency implementation. The degree of transparency (focused on how uncertain evidence was handled) during the development of folate and vitamin D Dietary Reference Values was explored in three a priori defined areas: (i) value request; (ii) evidence evaluation; and (iii) final values. Design Qualitative case studies (semi-structured interviews and desk research). A common protocol was used for data collection, interview thematic analysis and reporting. Results were coordinated via cross-case synthesis. Setting Australia and New Zealand, Netherlands, Nordic countries, Poland, Spain and UK. Subjects Twenty-one interviews were conducted in six case studies. Results Transparency of process was not universally observed across countries or areas of the recommendation setting process. Transparency practices were most commonly seen surrounding the request to develop reference values (e.g. access to risk manager/assessor problem formulation discussions) and evidence evaluation (e.g. disclosure of risk assessor data sourcing/evaluation protocols). Fewer transparency practices were observed to assist with handling uncertainty in the evidence base during the development of quantitative reference values. Conclusions Implementation of transparency policies may be limited by a lack of dedicated resources and best practice procedures, particularly to assist with the latter stages of reference value development. Challenges remain regarding the best practice for transparently communicating the influence of uncertain evidence on the final reference values. Resolving this issue may assist the evolution of nutrition risk assessment and better inform the recommendation setting process.

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Population models for multiple species provide one of the few means of assessing the impact of alternative management options on the persistence of biodiversity, but
they are inevitably uncertain. Is it possible to use population models in multiple-speciesconservation planning given the associated uncertainties? We use information-gap decision theory to explore the impact of parameter uncertainty on the conservation decision when planning for the persistence of multiple species. An information-gap approach seeks robust outcomes that are most immune from error. We assess the impact of uncertainty in key model parameters for three species, whose extinction risks under four alternative management scenarios are estimated using a metapopulation model. Three methods are described for making conservation decisions across the species, taking into account uncertainty. We find that decisions based on single species are relatively robust to uncertainty in parameters, although the estimates of extinction risk increase rapidly with uncertainty. When identifying the best conservation decision for the persistence of all species, the methods that rely on the rankings of the management options by each species result in decisions that are similarly robust to uncertainty. Methods that depend on absolute values of extinction risk are sensitive to uncertainty, as small changes in extinction risk can alter the ranking of the alternative scenarios. We discover that it is possible to make robust conservation decisions even when the uncertainties of the multiple-species problem appear overwhelming. However, the decision most robust to uncertainty is likely to differ from the best decision when uncertainty is ignored, illustrating the importance of incorporating uncertainty into the decision-making process.

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Despite its ubiquitous employment by users of English to achieve authentic communicative goals, taboo language has received little attention in the education literature. Even less focus has been placed on such language in English language teaching - specifically, in teaching English as an Additional Language (EAL). Given the multiplicity of communicative struggles experienced by EAL learners surrounding the use of taboo language in authentic communication, meaningful consideration of this aspect can be seen as crucial in EAL instruction. Classroom learning could prepare learners for navigation and negotiation of taboo language use they will inevitably encounter in social interactions in target language communities of practice. However, EAL teachers' uncertainty or reluctance to introduce taboo language in classroom instruction is a key impediment in developing learners' sociocultural knowledge regarding such language use. We foreground one case of such uncertainty and reluctance surrounding the introduction of taboo language in EAL instruction derived as interview data from an experienced EAL teacher.

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We extend the citizen candidate model of electoral competition with sincere voting to allow for k ≥ 2 states of aggregate uncertainty. We discuss and characterize the equilibrium set in this framework. We provide conditions for the existence of two-party equilibria when k = 2 and show that the policies of the two parties in any such equilibrium are not only divergent but that the parties are extremist: when the political mood is left-wing, the left-wing party wins decisively with a platform that is to the left of the left-wing median voter, while when the political mood is right-wing, the right-wing party wins decisively with a platform that is to the right of the right-wing median voter. We then provide conditions under which such equilibria remain robust for an arbitrary value of k.

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Conspiracy Theory (CT) endorsers believe in an omnipresent, malevolent, and highly coordinated group that wields secret influence for personal gain, and credit this group with the responsibility for many noteworthy events. Two explanations for the emergence of CTs are that they result from social marginalisation and a lack of agency, or that they are due to a need-to-explain-the-unexplained. Furthermore, representativeness heuristics may form reasoning biases that make such beliefs more likely. Two related studies (N = 107; N = 120) examined the relationships between these social marginalisation, intolerance of uncertainty, heuristics and CT belief using a correlational design. Overall, intolerance of uncertainty did not link strongly to CT belief, but worldview variables did - particularly a sense of the world as (socially) threatening, non-random, and with no fixed morality. The use of both representative heuristics that were examined was heightened in those participants more likely to endorse CTs. These factors seem to contribute to the likelihood of whether the individual will endorse CTs generally, relating similarly to common CTs, CTs generally historically accepted as "true", and to the endorsement of fictional CTs that the individual would find novel. Implications are discussed.

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Body size is a key determinant of metabolic rate, but logistical constraints have led to a paucity of energetics measurements from large water-breathing animals. As a result, estimating energy requirements of large fish generally relies on extrapolation of metabolic rate from individuals of lower body mass using allometric relationships that are notoriously variable. Swim-tunnel respirometry is the 'gold standard' for measuring active metabolic rates in water-breathing animals, yet previous data are entirely derived from body masses <10 kg - at least one order of magnitude lower than the body masses of many top-order marine predators. Here, we describe the design and testing of a new method for measuring metabolic rates of large water-breathing animals: a c. 26 000 L seagoing 'mega-flume' swim-tunnel respirometer. We measured the swimming metabolic rate of a 2·1-m, 36-kg zebra shark Stegostoma fasciatum within this new mega-flume and compared the results to data we collected from other S. fasciatum (3·8-47·7 kg body mass) swimming in static respirometers and previously published measurements of active metabolic rate measurements from other shark species. The mega-flume performed well during initial tests, with intra- and interspecific comparisons suggesting accurate metabolic rate measurements can be obtained with this new tool. Inclusion of our data showed that the scaling exponent of active metabolic rate with mass for sharks ranging from 0·13 to 47·7 kg was 0·79; a similar value to previous estimates for resting metabolic rates in smaller fishes. We describe the operation and usefulness of this new method in the context of our current uncertainties surrounding energy requirements of large water-breathing animals. We also highlight the sensitivity of mass-extrapolated energetic estimates in large aquatic animals and discuss the consequences for predicting ecosystem impacts such as trophic cascades.

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Natural hazards are complex events whose mitigation has generated a diverse field of specialised natural science expertise that is drawn upon by a wide range of practitioners and decision-makers. In this paper, the authors bring natural science research, risk studies and science and technology studies together in aid of clarifying the role scientific uncertainties play in the mitigation of natural hazards and their associated risks. Given that uncertainty is a necessary part of scientific practise and method, those engaged in risk mitigation must manage these scientific uncertainties in their decision-making just as, equally, social science researchers, stakeholders and others hoping to understand risk mitigation must understand their character and influence. To this end, the authors present the results of an extensive literature review of scientific uncertainties as they emerge in relation to wildfire and flood risk mitigation in Australia. The results are both a survey of these major uncertainties and a novel categorisation within which a variety of expert and non-expert audiences might discuss and translate the scientific uncertainties that are encountered and managed in risk mitigation.

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According to the DSM-IV- TR (American Psychiatric Association, 2000), one of the core deficits in autism is in the impairment of social interaction. Some have suggested that underlying these deficits is the reality that individuals with autism do not find social stimuli to be as reinforcing as other types of stimuli (Dawson, 2008). An interesting and growing body of literature supports the notion that symptoms in autism may be caused by a general reduction in social motivation (Chevallier et al., 2012). A review of the literature suggests that social orienting and social motivation are low in individuals with autism, and including social motivation as a target for therapeutic intervention should be pursued (Helt et al., 2008). Through our understanding of learning processes, researchers in behavior analysis and related fields have been able to use conditioning procedures to change the function of neutral or ineffective stimuli, including tokens (Ayllon & Azrin, 1968), facial expressions (Gewirtz & Pelaez-Nogueras, 1992) and praise (Dozier et al., 2012). The current study aimed to use operant and respondent procedures to condition social stimuli that were empirically shown to not be reinforcing prior to conditioning. Further, this study aimed to compare the two procedures in their effectiveness to condition social stimuli to function as reinforcers, and in their maintenance of effects over time. Using a multiple-baseline, multi-element design, one social stimulus was conditioned under each procedure to compare the different response rates following conditioning. Finally, the study sought to determine if conditioning social stimuli to function as reinforcers had any effect on the social functioning of young children with autism. Six children diagnosed with autism between the ages of 18 months and 3 years participated. Results show that the respondent procedure (pairing) resulted in more robust and enduring effects than the operant procedure (Sd procedure). Results of a social communication assessment (ESCS, Mundy et al., 2003) before and after conditioning demonstrate gains in all areas of social communication, particularly in the areas of initiating and responding to joint attention.

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Within corporate contexts, senior leaders must construct credible leadership identities if they are to demonstrate effectiveness in achieving business goals. This is a particular challenge for women, who have struggled historically to gain senior leadership positions. This chapter explores the identity struggles experienced by Karen, a woman Human Resources director within a management meeting as she delivers bad news about ‘company restructuring’ to her colleagues. Using Feminist Poststructuralist Discourse Analysis (FPDA), I show how this leader struggles to maintain a professionally competent identity as she negotiates the bad news. The analysis reveals that despite the demands of her role, Karen demonstrates extraordinary linguistic competence in managing her team within a turbulent business world that continues to remain inhospitable to female leaders.

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To generate realistic predictions, species distribution models require the accurate coregistration of occurrence data with environmental variables. There is a common assumption that species occurrence data are accurately georeferenced; however, this is often not the case. This study investigates whether locational uncertainty and sample size affect the performance and interpretation of fine-scale species distribution models. This study evaluated the effects of locational uncertainty across multiple sample sizes by subsampling and spatially degrading occurrence data. Distribution models were constructed for kelp (Ecklonia radiata), across a large study site (680 km2) off the coast of southeastern Australia. Generalized additive models were used to predict distributions based on fine-resolution (2·5 m cell size) seafloor variables, generated from multibeam echosounder data sets, and occurrence data from underwater towed video. The effects of different levels of locational uncertainty in combination with sample size were evaluated by comparing model performance and predicted distributions. While locational uncertainty was observed to influence some measures of model performance, in general this was small and varied based on the accuracy metric used. However, simulated locational uncertainty caused changes in variable importance and predicted distributions at fine scales, potentially influencing model interpretation. This was most evident with small sample sizes. Results suggested that seemingly high-performing, fine-scale models can be generated from data containing locational uncertainty, although interpreting their predictions can be misleading if the predictions are interpreted at scales similar to the spatial errors. This study demonstrated the need to consider predictions across geographic space rather than performance alone. The findings are important for conservation managers as they highlight the inherent variation in predictions between equally performing distribution models, and the subsequent restrictions on ecological interpretations.

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Conserving migratory species requires protecting connected habitat along the pathways they travel. Despite recent improvements in tracking animal movements, migratory connectivity remains poorly resolved at a population level for the vast majority of species, hampering conservation prioritisation. In the face of these data limitations, we develop a novel approach to spatial prioritisation based on a model of potential connectivity, derived from empirical data on species abundance and distances travelled between sites while on migration. Applying this approach to migratory shorebirds using the East Asian-Australasian Flyway, we demonstrate that conservation strategies that prioritise sites based on connectivity and abundance together, outperform strategies that only prioritise sites based on the abundance of birds. The conservation value of a site is therefore dependent on both its capacity to support migratory animals and its position within the migratory pathway, with the loss of crucial sites leading to partial or total population collapse. We suggest that strategies prioritising conservation action at sites supporting large populations of migrants should, where possible, be augmented using data or models on the spatial arrangement of sites.

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The main purpose of this study is to assess the relationship between four bioclimatic indices for cattle (environmental stress, heat load, modified heat load, and respiratory rate predictor indices) and three main milk components (fat, protein, and milk yield) considering uncertainty. The climate parameters used to calculate the climate indices were taken from the NASA-Modern Era Retrospective-Analysis for Research and Applications (NASA-MERRA) reanalysis from 2002 to 2010. Cow milk data were considered for the same period from April to September when the cows use the natural pasture. The study is based on a linear regression analysis using correlations as a summarizing diagnostic. Bootstrapping is used to represent uncertainty information in the confidence intervals. The main results identify an interesting relationship between the milk compounds and climate indices under all climate conditions. During spring, there are reasonably high correlations between the fat and protein concentrations vs. the climate indices, whereas there are insignificant dependencies between the milk yield and climate indices. During summer, the correlation between the fat and protein concentrations with the climate indices decreased in comparison with the spring results, whereas the correlation for the milk yield increased. This methodology is suggested for studies investigating the impacts of climate variability/change on food and agriculture using short term data considering uncertainty.

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The paper discusses the evaluation of the uncertainty of a multivariate quantity using the Law of Propagation of Uncertainty defined in the Guide to the Expression of Uncertainty in Measurement (GUM) and a Monte Carlo method according to the GUM’s Supplement 2. The quantity analysed is the electrical impedance, which is not a scalar but a complex quantity. The used measuring method allows the evaluation of the impedance and of its uncertainty in different ways and the corresponding results are presented, compared and discussed. For comparison purposes, results of the impedance uncertainty obtained using the NIST Uncertainty Machine are also presented.