DYNAMICS OF CHOICE: RELATIVE RATE AND AMOUNT AFFECT LOCAL PREFERENCE AT THREE DIFFERENT TIME SCALES

To examine extended control over local choice, the present study investigated preference in transition as food‐rate ratio provided by two levers changed across seven components within daily sessions, and food‐amount ratio changed across phases. Phase 1 arranged a food‐amount ratio of 4:1 (i.e., the left lever delivered four pellets and the right lever one pellet); Phase 2 reversed the food‐amount ratio to 1:4, and in Phase 3 the food‐amount ratio was 3:2. At a relatively extended time scale, preference was described well by a linear relation between log response ratio and log rate ratio (the generalized matching law). A small amount of carryover occurred from one rate ratio to the next but disappeared after four food deliveries. Estimates of sensitivity to food‐amount ratio were around 1.0 and were independent of rate ratio. Analysis across food deliveries within rate‐ratio components showed that the effect of a small amount was diminished by the presence of a large amount—that is, when a larger amount was present in the situation (three or four pellets), the value of a small amount (one or two pellets) became paltry. More local analysis of visits to the levers between food deliveries showed that postfood visits following a large amount were disproportionately longer than following a small amount. Continuing food deliveries from the same source tended to make visits less dependent on relative amount, but a discontinuation (i.e., food from the other lever) reinstated dependence on relative amount. Analysis at a still smaller time scale revealed preference pulses following food deliveries that confirmed the tendency toward dependence on absolute amount with continuing deliveries, and toward dependence on relative amount following discontinuations. A mathematical model based on a linear‐operator equation accounts for many of the results. The larger and longer preference following a switch to a larger amount is consistent with the idea that local preference depends on relatively extended variables even on short time scales.     

基于计算机仿真的颜色认知实验方法研究

近年来计算机仿真的实验研究方法逐渐成为颜色认知研究的主流方法,该方法克服了传统方法的诸多缺陷。本研究在现有技术的基础上构建了颜色研究仿真系统,并改进了CIE规定的有关CRT显示器颜色标定的方法。笔者通过颜色匹配实验考察了人对CRT显示器上仿真照明体颜色外观的辨别精度,结果表明上述颜色仿真系统在颜色认知实验中具有良好的适用性,并发现被试在计算机模拟颜色刺激的条件下,可进行精确的颜色匹配;不同照明条件下的色差有所不同。这些结果也为建立颜色认知模型提供了人的基准匹配数据。     

Does matching up features mess up job choice? Boundary conditions on attribute‐salience effects

Research in decision making has suggested that the degree to which features of an option are shared versus unique influences preferences in a way that violates normative rules. The generalizability of these findings to job choice was investigated. Senior‐level, undergraduate job seekers (N = 216) were presented with three jobs from which they were asked to choose one. Attributes for two of the jobs (A and B) remained invariant across conditions, and attributes for a third job (C) were manipulated such that it shared unfavorable features with one of the invariant jobs (A or B) and favorable attributes with the other job (B or A). Results suggested that jobs with unique positive features and shared negative features were preferred over those with unique negative features and shared positive features only when information was presented in a simple (versus complex) format and when participants did not rate the importance of attributes prior to the choice task. We suggest that inferences from feature‐matching research should be qualified by these boundary conditions. Copyright © 2002 John Wiley & Sons, Ltd.     

Effects of stimulus presentation order during auditory–visual conditional discrimination training for children with autism spectrum disorder

Children with autism spectrum disorder are typically taught conditional discriminations using a match‐to‐sample arrangement. Consideration should be given to the temporal order in which antecedent stimuli (the sample and comparison stimuli) are presented during match‐to‐sample trials, as various arrangements have been used in the extant literature. The purpose of the current study was to compare the effects of four stimulus presentation orders on the acquisition of auditory–visual conditional discriminations. The study included participants from a clinically relevant population (three children with autism spectrum disorder), employed clinically relevant teaching procedures, and included two presentation formats not included in previous comparison evaluations (simultaneous and sample‐first with re‐presentation conditions). Results were found to be learner‐specific; that is, a different stimulus presentation format was most efficient for each participant. We provide suggestions to evaluate stimulus control topographies and enhance experimental control in match‐to‐sample arrangements.     

Acquisition and generative responding following print‐to‐braille construction response training with sighted learners

Previous researchers have taught sighted adults to match braille sample stimuli to print comparisons in a matching‐to‐sample (MTS) format and assessed the emergence of other braille repertoires, such as transcribing and reading braille following this training. Although participants learned to match to sample with braille, they displayed limited emergence of other braille repertoires. Lack of generative responding may have resulted from participants' over‐selective attending to components of compound braille characters during instruction. We taught undergraduates to construct braille characters given a print sample, which required attending to each individual braille symbol, and assessed generative braille responding. Participants met mastery of 378 braille construction responses and demonstrated modestly improved responding compared with previous research.     

Local effects of delayed food

Five pigeons were trained on a procedure in which seven concurrent variable-interval schedules arranged seven different food-rate ratios in random sequence in each session. Each of these components lasted for 10 response-produced food deliveries, and components were separated by 10-s blackouts. We varied delays to food (signaled by blackout) between the two response alternatives in an experiment with three phases: In Phase 1, the delay on one alternative was 0 s, and the other was varied between 0 and 8 s; in Phase 2, both delays were equal and were varied from 0 to 4 s; in Phase 3, the two delays summed to 8 s, and each was varied from 1 to 7 s. The results showed that increasing delay affected local choice, measured by a pulse in preference, in the same way as decreasing magnitude, but we found also that increasing the delay at the other alternative increased local preference. This result casts doubt on the traditional view that a reinforcer strengthens a response depending only on the reinforcer's value discounted by any response-reinforcer delay. The results suggest that food guides, rather than strengthens, behavior.     

Further analysis of the matching law to describe two- and three-point shot allocation by professional basketball players

The matching law was used to analyze whether the proportion of shots taken from two- or three-point range would match the proportional reinforcement rates produced by those shots when the reinforcement rate of three-point shooting was changed. Rule changes in 1994 and 1997 altered the distance of the three-point line in the National Basketball Association, which created a quasiexperimental reversal design, thereby naturally changing three-point reinforcement rates. The present data partially confirmed predictions made by the matching law, in that increases in the relative rate of three-point shots attempted corresponded to increases in the relative rate of three-point shots made.     

Effects of delayed constructed-response identity matching on spelling of dictated words

We studied the effects of delayed constructed-response identity matching on spelling with 6 first graders with histories of school failure. After training, the children learned to spell words to dictation and their cursive writing improved. These results replicate studies showing that delayed constructed-response matching establishes spelling. For 2 children, spelling of generalization words--words formed by recombining the syllables of training words--also improved. These results extend studies that have shown recombinative generalization in reading and spelling.