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271.
Charlene Hallett Anthony Lambert Michael A. Regan 《Transportation Research Part F: Traffic Psychology and Behaviour》2012,15(3):261-271
Recent work suggests that text messaging impairs simulated and actual driving performance and that this impairment exceeds that of conversing on a cell phone while driving. Additionally, research has shown that text messaging is common in several countries, and despite drivers acknowledging the high risk involved in doing so, drivers continue to engage in this behaviour – regardless of legislation banning it. A nationwide online survey in New Zealand, of 1057 respondents, collected anonymous self-report data regarding the frequency of cell phone use (conversing and text messaging) while driving, beliefs concerning the safety of conversing or text messaging while driving. This article presents part of the results of that study – focusing on text messaging behaviour and risk perception regarding text messaging while driving. Over half of respondents surveyed reported sending or reading between 1 and 5 text messages while driving in a typical week. Despite this, 89% of participants agreed that text messaging while driving in general impairs driving performance. There were no gender differences between the number of text messages read and sent. Age was found to be an important indicator of participant’s willingness to engage in text messaging while driving, with younger drivers more likely to engage in this behaviour. The implications of these findings for future research and countermeasure development are discussed. 相似文献
272.
Anthony Wrigley 《Ethical Theory and Moral Practice》2012,15(2):175-190
Non-Identity arguments have a pervasive but sometimes counter-intuitive grip on certain key areas in ethics. As a result,
there has been limited success in supporting the alternative view that our choices concerning future generations can be considered
harmful on any sort of person-affecting principle. However, as the Non-Identity Problem relies overtly on certain metaphysical
assumptions, plausible alternatives to these foundations can substantially undermine the Non-Identity argument itself. In
this paper, I show how the pervasive force and nature of Non-Identity arguments rely upon a specific adoption of a theory
of modality and identity and how adopting an alternative account of modality can be used to reject many conclusions formed
through Non-Identity type arguments. By using Lewis’s counterpart-theoretic account to understand ways we might have been,
I outline the basis of a modal account of harm that incorporates a person-affecting aspect. This, in turn, has significant
implications for ethical decision-making in areas such as reproductive choice and the welfare of future generations. 相似文献
273.
Belief revision is the problem of finding the most plausible explanation for an observed set of evidences. It has many applications in various scientific domains like natural language understanding, medical diagnosis and computational biology. Bayesian Networks (BN) is an important probabilistic graphical formalism widely used for belief revision tasks. In BN, belief revision can be achieved by finding the maximum a posteriori (MAP) assignment. Finding MAP is an NP-Hard problem. In previous work, we showed how to find the MAP assignment in BN using High Order Recurrent Neural Networks (HORN) through an intermediate representation of Cost-Based Abduction. This method eliminates the need to explicitly construct the energy function in two steps, objective and constraints. This paper builds on that previous work by providing the theoretical foundation and proving that the resultant HORN used to find MAP is strongly equivalent to the original BN it tries to solve. 相似文献
274.
The Bengalese finch (Lonchura striata var. domestica) is a species of songbird. Males sing courtship songs with complex note-to-note transition rules, while females discriminate
these songs when choosing their mate. The present study uses serial reaction time (RT) to examine the characteristics of the
Bengalese finches’ sequential behaviours beyond song production. The birds were trained to produce the sequence with an “A–B–A”
structure. After the RT to each key position was determined to be stable, we tested the acquisition of the trained sequential
response by presenting novel and random three-term sequences (random test). We also examined whether they could abstract the
embedded rule in the trained sequence and apply it to the novel test sequence (abstract test). Additionally, we examined rule
abstraction through example training by increasing the number of examples in baseline training from 1 to 5. When considered
as (gender) groups, training with 5 examples resulted in no statistically significant differences in the abstract tests, while
statistically significant differences were observed in the random tests, suggesting that the male birds learned the trained
sequences and transferred the abstract structure they had learned during the training trials. Individual data indicated that
males, as opposed to females, were likely to learn the motor pattern of the sequence. The results are consistent with observations
that males learn to produce songs with complex sequential rules, whereas females do not. 相似文献
275.
Non-human primates possess species-specific repertoires of acoustically distinct call types that can be found in adults in
predictable ways. Evidence for vocal flexibility is generally rare and typically restricted to acoustic variants within the
main call types or sequential production of multiple calls. So far, evidence for context-specific call sequences has been
mainly in relation to external disturbances, particularly predation. In this study, we investigated extensively the vocal
behaviour of free-ranging and individually identified Diana monkeys in non-predatory contexts. We found that adult females
produced four vocal structures alone (‘H’, ‘L’, ‘R’ and ‘A’ calls, the latter consisting of two subtypes) or combined in non-random
ways (‘HA’, ‘LA’ and ‘RA’ call combinations) in relation to ongoing behaviour or external events. Specifically, the concatenation
of an introductory call with the most frequently emitted and contextually neutral ‘A’ call seems to function as a contextual
refiner of this potential individual identifier. Our results demonstrate that some non-human primates are able to increase
the effective size of their small vocal repertoire not only by varying the acoustic structure of basic call types but also
by combining them into more complex structures. We have demonstrated this phenomenon for a category of vocalisations with
a purely social function and discuss the implications of these findings for evolutionary theories of primate vocal communication. 相似文献
276.
It has been speculated that cage mesh exerts a shaping influence on reaching behavior by captive apes, which is then misconstrued
as pointing by human observers. Although this notion is clearly falsified by the pointing of captive language-trained apes—who
point in the absence of intervening cage mesh—nevertheless, the degree to which cage mesh might influence pointing hand shapes
by captive great apes in other housing environments remains relatively unexplored. We examined 259 pointing gestures displayed
in archival footage from over 18 h of observation by three nonlanguage-trained chimpanzees housed at a biomedical research
center. We coded points in relation to how close to the boundaries of the diamond-shaped cage mesh their points were displayed.
We found that points with the whole hand were significantly more likely to be displayed away from the mesh boundaries, relative
to points with the index finger or other single-digit points. However, points of each hand shape were displayed at each location,
demonstrating that these physical parameters do not fully account for the number of fingers extended while pointing by chimpanzees. 相似文献
277.
Although rats are able to build complex spatial representations of their surroundings during exploration, the nature of the
encoded information is still a matter for debate. In particular, it is not well established if rats can process the topological
structure of the environment in such a way that they are aware of the connections existing between remote places. Here, rats
were first exposed for four 5-min trials to a complex environment divided into several sectors that were separated by doors
allowing either unrestricted or restricted access to other sectors. In the fifth test trial, we measured the behavior of the
animals while they explored the same environment in which, however, they faced changes that either altered or did not alter
the topological structure of the environment. In experiment 1, closing previously opened doors prevented the rat from having
direct access between corresponding sectors. In experiment 2, opening previously closed doors allowed direct access between
sectors that had not been directly accessible. In each experiment, control doors allowed us to discard the mere influence
of door manipulation. We compared the rats’ exploratory behavior in response to door manipulations that either strongly altered
or did not alter the ability to commute between sectors and found evidence that the animals displayed differential reactions
to the two types of door manipulations. This implies that during exploration rats build a precise map of the connectivity
of space that can be flexibly updated and used for efficient navigation. 相似文献
278.
Uneconomical choices by humans or animals that evaluate reward options challenge the expectation that decision-makers always
maximize the return currency. One possible explanation for such deviations from optimality is that the ability to sense differences
in physical value between available alternatives is constrained by the sensory and cognitive processes for encoding profitability.
In this study, we investigated the capacity of a nectarivorous bat species (Glossophaga commissarisi) to discriminate between sugar solutions with different concentrations. We conducted a two-alternative free-choice experiment
on a population of wild electronically tagged bats foraging at an array of computer-automated artificial flowers that recorded
individual choices. We used a Bayesian approach to fit individual psychometric functions, relating the strength of preferring
the higher concentration option to the intensity of the presented stimulus. Psychometric analysis revealed that discrimination
ability increases non-linearly with respect to intensity. We combined this result with a previous psychometric analysis of
volume perception. Our theoretical analysis of choice for rewards that vary in two quality dimensions revealed regions of
parameter combinations where uneconomic choice is expected. Discrimination ability may be constrained by non-linear perceptual
and cognitive encoding processes that result in uneconomical choice. 相似文献
279.
Simon R. Walters Philip J. Schluter Anthony R.H. Oldham 《Psychology of sport and exercise》2012,13(2):208-215
Objectives
This study aimed to establish the prevalence, pattern and nature of coaches’ verbal behaviour at children’s (ages 6-12 years) team sports events. The study draws upon the motivational model presented by Mageau and Vallerand (2003) to examine the influence of global (gender), contextual (sport related), and social (athlete gender) factors on coach comments.Design
A cross-sectional observational study of coaches stratified across four team sports: Rugby Union, Netball, Association Football and Touch Rugby.Method
The Observation Instrument at Sports Events was used to categorise covertly recorded verbal comments made by coaches at organised team sports games.Results
Overall, 10,697 comments were recorded at 72 games at a rate of 3.71 comments/minute; 35.4% were categorised as positive, 21.6% as negative, and 43.0% as neutral. Significant differences in negative comments were identified between sport (p < .001) with rugby coaches recording the highest percentage of negative comments and the lowest percentage of positive comments; by coach gender (p < .001), with male coaches recording higher rates of negative comments; and by athlete gender (p < .001), with coaches of male-only teams recording higher rates of negative comments. When simultaneously included in a Poisson regression model the difference in negative comments between sports remained statistically significant (p < .001) whereas coach gender was no longer significant.Conclusions
The ratio of negative coach comments for all sports gives cause for concern. These findings suggest that sports of national and cultural significance are a key driver of coaching behaviours in a competitive environment. 相似文献280.
Different event-related potentials (ERPs) have been shown to correlate with learning from feedback in decision-making tasks
and with learning in explicit memory tasks. In the present study, we investigated which ERPs predict learning from corrective
feedback in a multiple-choice test, which combines elements from both paradigms. Participants worked through sets of multiple-choice
items of a Swahili–German vocabulary task. Whereas the initial presentation of an item required the participants to guess
the answer, corrective feedback could be used to learn the correct response. Initial analyses revealed that corrective feedback
elicited components related to reinforcement learning (FRN), as well as to explicit memory processing (P300) and attention
(early frontal positivity). However, only the P300 and early frontal positivity were positively correlated with successful
learning from corrective feedback, whereas the FRN was even larger when learning failed. These results suggest that learning
from corrective feedback crucially relies on explicit memory processing and attentional orienting to corrective feedback,
rather than on reinforcement learning. 相似文献