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1.
Theories of probabilistic reinforcement.   总被引:9,自引:8,他引:1  
In three experiments, pigeons chose between two alternatives that differed in the probability of reinforcement and the delay to reinforcement. A peck at a red key led to a delay of 5 s and then a possible reinforcer. A peck at a green key led to an adjusting delay and then a certain reinforcer. This delay was adjusted over trials so as to estimate an indifference point, or a duration at which the two alternatives were chosen about equally often. In Experiments 1 and 2, the intertrial interval was varied across conditions, and these variations had no systematic effects on choice. In Experiment 3, the stimuli that followed a choice of the red key differed across conditions. In some conditions, a red houselight was presented for 5 s after each choice of the red key. In other conditions, the red houselight was present on reinforced trials but not on nonreinforced trials. Subjects exhibited greater preference for the red key in the latter case. The results were used to evaluate four different theories of probabilistic reinforcement. The results were most consistent with the view that the value or effectiveness of a probabilistic reinforcer is determined by the total time per reinforcer spent in the presence of stimuli associated with the probabilistic alternative. According to this view, probabilistic reinforcers are analogous to reinforcers that are delivered after variable delays.  相似文献   

2.
It is widely assumed that the allocation of spatial attention results in the "selection" of attended objects or regions of space. That is, once a stimulus is attended, all its feature dimensions are processed irrespective of their relevance to behavioral goals. This assumption is based in part on experiments showing significant interference for attended stimuli when the response to an irrelevant dimension conflicts with the response to the relevant dimension (e.g., the Stroop effect). Here we show that such interference is not due to attending per se. In two spatial cuing experiments, we found that it was possible to restrict processing of attended stimuli to task-relevant dimensions. This new evidence supports two novel conclusions: (a) Selection involves more than the focusing of attention per se; and (b) task expectations play a key role in determining the depth of processing of the elementary feature dimensions of attended stimuli.  相似文献   

3.
Pigeons chose between two alternatives that differed in the probability of reinforcement and the delay to reinforcement. A peck on the red key always produced a delay of 5 s and then a possible reinforcer. The probability of reinforcement for responding on this key varied from .05 to 1.0 in different conditions. A response on the green key produced a delay of adjustable duration and then a possible reinforcer, with the probability of reinforcement ranging from .25 to 1.0 in different conditions. The green-key delay was increased or decreased many times per session, depending on a subject's previous choices. The purpose of these adjustments was to estimate an indifference point, or a delay that resulted in a subject's choosing each alternative about equally often. In conditions where the probability of reinforcement was five times higher on the green key, the green-key delay averaged about 12 s at the indifference point. In conditions where the probability of reinforcement was twice as high on the green key, the green-key delay at the indifference point was about 8 s with high probabilities and about 6 s with low probabilities. An analysis based on these results and those from studies on delay of reinforcement suggests that pigeons' choices are relatively insensitive to variations in the probability of reinforcement between .2 and 1.0, but quite sensitive to variations in probability between .2 and 0.  相似文献   

4.
The agent-relative/agent-neutral distinction is one of the most important in contemporary moral theory. Yet providing an adequate formal account of it has proven to be difficult. In this article I defend a new formal account of the distinction, one that avoids various problems faced by other accounts. My account is based on an influential account of the distinction developed by McNaughton and Rawling. I argue that their approach is on the right track but that it succumbs to two serious objections. I then show how to formulate a new account that follows the key insights of McNaughton and Rawling's approach yet avoids the two objections.  相似文献   

5.
Due to racioethnic and sex subgroup differences on predictor scores in many selection procedures, it is difficult for organizations to simultaneously maximize the validity of their selection procedures and hire a diverse workforce. One response to this diversity–validity dilemma is to revise the selection procedures, an approach developed by Ployhart and Holtz (this issue, 2008) . A second possible response is to use affirmative action to increase workforce diversity, an approach developed by Kravitz (this issue, 2008) . This paper briefly presents the legal context that motivates and constrains these approaches. We begin by defining key terms, describing adverse impact, and outlining the burden of proof in adverse impact cases. We then turn to the use of racioethnic minority and female preferences, summarizing some key court decisions and the conditions under which private and public employers may use preferences.  相似文献   

6.
Temporomandibular dysfunction (TMD) pain, like many chronic pain problems, appears to be multiply determined. Patients with TMD pain of at least 6 months duration (N = 30) were administered questionnaires measuring dispositional coping styles and appraisals to explore the dynamic interactions of the pain and coping process. Patients were then issued handheld computers that prompted them to record their momentary pain and coping processes 4 times per day for 7 days. Hierarchical linear regression models using both the dispositional and momentary predictors indicated that momentary pain was a function both of dispositional tendency to catastrophize and of momentary measures of catastrophization, self-efficacy, and mood states. Results were seen as supporting a situational model of intervention for chronic TMD pain.  相似文献   

7.
In two experiments, we studied how people’s strategy choices emerge through an initial and then a more considered evaluation of available strategies. The experiments employed a computer-based paradigm where participants solved multiplication problems using mental and calculator solutions. In addition to recording responses and solution times, we gathered data on mouse cursor movements. Participants’ motor behavior was revealing; although people rapidly initiated movement to the calculator box or the answer input box, they frequently changed their minds and went to the other box. Movement initiation direction depended on problem difficulty and calculator responsiveness. Ultimate strategy selection also depended on these factors, but was further influenced by movement initiation direction. We conclude that strategy selection is iterative, as revealed by these differences between early cursor movement and eventual strategy implementation. After rapidly initiating movement favoring one strategy, people carefully evaluate the applicability of that strategy in the current context.  相似文献   

8.
This study examined the hypothesis that a key process in conditional reasoning with concrete premises involves on-line retrieval of information about potential alternate antecedents. Participants were asked to solve reasoning problems with causal conditional premises (If cause P then effect Q). These premises were inserted into short contexts. The availability of potential alternatives was varied from one context to another by adding statements that explicitly invalidated one or more of these alternatives (i.e., other causes that lead to the effect (Q). The invalidated alternatives differed in the degree of their semantic association to the consequent term (Q). The results show that the effect of invalidating one or more potential alternatives on the two uncertain logical forms, AC and DA, was largely determined by their relative associative strength. These results strongly support a model for conditional reasoning with causal premises that supposes that a key element in responding to the uncertain logical forms is on-line retrieval of at least one potential alternative antecedent.  相似文献   

9.
Manktelow and Over (1991) argue that their studies of Wason's selection task favor explanations of deontic reasoning based on mental models, but that such theories need to incorporate utilities. This theoretical note proposes a simpler explanation of the phenomena: subjects in the selection task consider only those cards that are explicitly represented in their models of the conditional, and so insight into the task depends on constructing fully explicit models. Such models for modal conditionals of the form, If p occurs then q may occur are: [formula: see text] Each line denotes a separate model, and the models represent either what is possible, or, in the deontic interpretation, what is permissible. A deontic rule is accordingly violated by the contingency: [symbol: see text] p and q, for example the rule, "If you spend more than 100 pounds, then you may take a free gift" is violated by taking the free gift (q) but not spending more than 100 pounds ([symbol: see text] p). If the rule is interpreted as a bi-conditional, then the second of the models, p and [symbol: see text] q, is also now a violation, for example spending more than 100 pounds (p) but not getting the free gift ([symbol: see text] q). Manktelow and Over's instructions lead subjects to focus on one or other of the two sorts of violations of the rule. There is accordingly no need to introduce utilities into models in order to explain the phenomena.  相似文献   

10.
Creativity scholars try to untangle the commonalities and differences between creative self-beliefs: creative self-efficacy, creative self-concept, creative metacognition, and creative role identity. While these efforts are already contributing significantly, we would like to suggest that for creative metacognition, we need to go beyond the assessment of confidence beliefs and regulation and include creative metacognitive feelings and intrapersonal idea selection as two additional components. To test the validity of our proposition, this study examined the influence of creative metacognitive feelings on creative self-efficacy, creative potential, accurate intrapersonal idea selection (agreement between individuals’ selection of their most creative idea and two independent judges’ selection of the participants’ best idea), and task enjoyment. To elicit metacognitive feelings, participants were randomly assigned to remember and write down two or six instances in their lives in which they generated novel and useful ideas that helped solve a problem. Participants then completed a questionnaire assessing creative self-efficacy, ease of recall as a proxy of metacognitive feelings, performance on a divergent thinking task, and task enjoyment. Results showed an indirect influence of recalling fewer examples on creative self-efficacy through its influence on metacognitive feelings. Metacognitive feelings then had an indirect influence, through creative self-efficacy, on creative potential and task enjoyment.  相似文献   

11.
Transfer of matching performance in pigeons.   总被引:1,自引:0,他引:1       下载免费PDF全文
Three pigeons were given extensive training on three-key simultaneous matching problems using geometric-form and hue stimuli. After acquisition of matching, the birds were tested with pairs of stimuli involving one or both novel members. Matching during the test stimuli occurred less often than during the later stages of the acquisition phase, but more often than would occur if no transfer had taken place. Greater positive transfer was observed for problems that involved one, rather than two, novel stimuli. In the second phase of the experiment, previously trained birds were shifted to problems that required symbolic matching, i.e., the pigeons had to associate a particular center-key stimulus with a particular side-key stimulus. On each trial, one of two simuli was presented on the center key, and two other stimuli, different from those used on the center key, were displayed on the side keys. When the problem shift was introduced, correct responding was impaired, but remained considerably above chance level and quickly recovered in following sessions. The results were interpreted as favoring a stimulus-response-chaining account of matching behavior.  相似文献   

12.
Pashler (this issue) concluded that the rate of responding in serial choice reaction tasks was controlled by a limit on simultaneous response selection rather than on simultaneous response execution. Film of a skilled typist shows that each finger movement starts as a key earlier in the sequence to be typed is struck (three earlier with words, two with orthographically legal non-words). Thus, her rate of responding is controlled by a limit on the number of responses that can be executed simultaneously, not by a limit on response selection.

Preventing simultaneous response selection is one possible strategy for maintaining correct response order in serial tasks. It is suitable for tasks such as those studied by Pashler, where response selection is relatively slow and response execution is quick. Other strategies are more suitable for tasks where response selection is quick and response execution relatively slow and variable.  相似文献   

13.
The assumption that people possess a repertoire of strategies to solve the inference problems they face has been raised repeatedly. However, a computational model specifying how people select strategies from their repertoire is still lacking. The proposed strategy selection learning (SSL) theory predicts a strategy selection process on the basis of reinforcement learning. The theory assumes that individuals develop subjective expectations for the strategies they have and select strategies proportional to their expectations, which are then updated on the basis of subsequent experience. The learning assumption was supported in 4 experimental studies. Participants substantially improved their inferences through feedback. In all 4 studies, the best-performing strategy from the participants' repertoires most accurately predicted the inferences after sufficient learning opportunities. When testing SSL against 3 models representing extensions of SSL and against an exemplar model assuming a memory-based inference process, the authors found that SSL predicted the inferences most accurately.  相似文献   

14.
We studied human movement planning in tasks in which subjects selected one of two goals that differed in expected gain. Each goal configuration consisted of a target circle and a partially overlapping penalty circle. Rapid hits into the target region led to a monetary bonus; accidental hits into the penalty region incurred a penalty. The outcomes assigned to target and penalty regions and the spatial arrangement of those regions were varied. Subjects preferred configurations with higher expected gain whether selection involved a rapid pointing movement or a choice by key press. Movements executed to select one of two goal configurations exhibited the same movement dynamics as pointing movements directed at a single configuration, and were executed with the same high efficiency. Our results suggest that humans choose near-optimal strategies when planning their movement, and can base their selection of strategy on a rapid judgment about the expected gain associated with possible movement goals.  相似文献   

15.
Cheng and Holyoak (1985) have proposed that people possess classes of linguistically based schemas that have an internal structure that is determined by pragmatic considerations. They found that when permission schemas (“If you want to do P, then you must do Q”) are used in the selection task, the success rate is much superior to what is usually observed. According to Cheng and Holyoak, this is due to the fact that the permission schema is defined by a set of production rules that give the same answers to problems of conditional inference as those of formal logic. In order to test this hypothesis specifically, 160 university students were given one of two tests. The first contained two sets of inferential reasoning tasks, one using a permission schema, the second using a relation of multiple causality. The second test employed the same two conditional relations, but in an appropriate context. The results indicated that subjects did better on the reasoning task with the schema of multiple causality when presented in context, but, as predicted, their performance was much worse on the inferential reasoning task with the permission schema, which generated a higher proportion of logically incorrect responses. These results suggest that contrary to what has been affirmed, permission schemas might not have a logical structure that is equivalent to conditional logic. A second experiment examined selection task performance using the same two relations in context. Performance on the permission schema was superior to that found with the relation of multiple causality. This confirmed previous results indicating that permission schemas do improve selection task performance, but also suggests that this effect is not related to understanding of conditional reasoning.  相似文献   

16.
The impact of time online: social capital and cyberbalkanization.   总被引:1,自引:0,他引:1  
Hypotheses and research questions about the Internet displacing social capital, atomizing users, creating loneliness, and creating new forms of community were addressed through an original survey of Internet users. A key innovation of this research is that it collects parallel measures of social capital for online and offline contexts, which can then be compared. The results show that while Internet use does suggest a displacing effect, it is also a source of new, qualitatively different social capital. However, there is no connection between Internet use and atomization (or out-group antagonism), and the latter is actually lower online. Taken together, the results suggest that the Internet is no panacea but is not a direct source of problems either. More likely is the case that the costs and benefits for individuals will be predicted by their personalities and particular kinds of Internet use. The results are discussed, along with their implications for theory and future research.  相似文献   

17.
《Intelligence》1986,10(3):239-250
It is proposed that the centrality of intellectual abilities can be assessed in terms of two criteria: (a) the generality of the ability in performances on tasks requiring adaptation to, selection of, and shaping of, real-world environments, and (b) the necessity of these abilities in performing these tasks. The two criteria taken together are given the acronym GENECES (Generality and NECESsity). The article opens with a discussion of the problems of arbitrariness of criteria for deciding on tests to measure central intellectual abilities—first for a posteriori bases of criteria selection, and second for a priori criteria. The article then discusses why the GENECES framework may be useful in selecting tasks and in evaluating the centrality of abilities to intelligence.  相似文献   

18.
Leading models of obsessive-compulsive disorder (OCD) implicate thought suppression as a key factor in the escalation and persistence of the disorder. This experiment examined the effects of suppression on the frequency of obsessional thoughts in 50 individuals with a primary diagnosis of OCD, and also investigated the effects of participants' appraisals regarding their failures in thought control on distress about intrusive thoughts and on mood. Participants' most upsetting obsessional thought was primed and they then monitored its occurrence over two 4-min intervals. In the first interval, half of the participants were instructed to suppress their obsessional thought and half were instructed not to suppress any thoughts. In the second interval, all participants were given the 'Do Not Suppress' instructions. Participants rated their suppression effort and discomfort over thought occurrences after each interval and recorded their appraisals of thought recurrences during the first interval. Mood state was then reassessed. No ironic effect of suppression on frequency was noted. However, negative appraisals of thought recurrences were associated with more discomfort over thought occurrences and more negative mood at Time 2. These findings suggest that interpretations regarding failures in thought control may be of central importance in understanding obsessional problems.  相似文献   

19.
20.
Accessing words in speech production: stages, processes and representations.   总被引:11,自引:0,他引:11  
W J Levelt 《Cognition》1992,42(1-3):1-22
This paper introduces a special issue of Cognition on lexical access in speech production. Over the last quarter century, the psycholinguistic study of speaking, and in particular of accessing words in speech, received a major new impetus from the analysis of speech errors, dysfluencies and hesitations, from aphasiology, and from new paradigms in reaction time research. The emerging theoretical picture partitions the accessing process into two subprocesses, the selection of an appropriate lexical item (a "lemma") from the mental lexicon, and the phonological encoding of that item, that is, the computation of a phonetic program for the item in the context of utterance. These two theoretical domains are successively introduced by outlining some core issues that have been or still have to be addressed. The final section discusses the controversial question whether phonological encoding can affect lexical selection. This partitioning is also followed in this special issue as a whole. There are, first, four papers on lexical selection, then three papers on phonological encoding, and finally one on the interaction between selection and phonological encoding.  相似文献   

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