PREFERENCE REVERSALS DUE TO MYOPIC DISCOUNTING OF DELAYED REWARD

Abstract— A basic stationarity axiom of economic theory assumes stable preference between two deferred goods separated by a fixed time. To test this assumption, we offered subjects choices between delayed rewards, while manipulating the delays to those rewards. Preferences typically reversed with changes in delay, as predicted by hyperbolic discounting models of impulsiveness. Of 36 subjects, 34 reversed preference from a larger, later reward to a smaller, earlier reward as the delays to both rewards decreased. We conclude that the stationarity axiom is not appropriate in models of human choice.     

THE REWARDS AND HAZARDS OF COMPUTER SIMULATIONS

Although computer simulations and other modeling tools have assumed a pivotal role in cognitive psychology, their utility continues to be questioned by some psychologists. This article presents several examples that illustrate both rewards and potential hazards associated with the simulation approach. Simulations can provide the formal framework necessary to disambiguate new ideas, they can explore the implications of complex models, and they can predict seemingly counterintuitive findings or uncover hidden relationships. At the same time, care must be taken to avoid pitfalls that may arise when computer code inadvertently differs from the intended specifications of a theory, or when predictions derive not from fundamental properties of a theory but from pragmatic choices made by the modeler.     

THE DEVELOPMENT AND GENERALIZATION OF DELAYED IMITATION1

An individual's behavior can be identified as imitative if it temporally follows the behavior of another individual and if its topography is controlled by the demonstrated behavior [Baer, Peterson, and Sherman (Journal of the Experimental Analysis of Behavior, 1967, 10 , 405–416)]. This definition takes into account both temporal and topographical characteristics of the behavior in question. More recent research in the area of imitation has interpreted the temporal component of the above definition differentially by limiting imitation to those topographically similar responses occurring within 3, 5, or 10 sec after a model's demonstration. Yet, Gewirtz and Stingle (Psychological Review, 1968, 75 , 375–397) pointed out that much of the imitation seen in young children is not of this immediate nature, but instead occurs sometime after a model's response. They further suggest that this type of imitative behavior can be characterized as a response class and is susceptible to development and modification as a function of consequences delivered to subjects contingent on this type of delayed responding. Four retarded children, three initially imitative and one nonimitative, were individually trained to imitate a number of motor responses in an immediate and a delayed fashion. Immediate imitation was defined as a response similar to a model's demonstration occurring within 5 sec after the model's demonstration; delayed imitation was defined as a response similar to a model's demonstration occurring more than 5 sec, but not more than 25 sec, after the model's demonstration. A reversal (ABAB) design was employed to examine the experimental development of a generalized delayed imitative repertoire. Untrained probe responses were demonstrated to subjects systematically through the ongoing training. Generalized immediate and delayed imitation were observed in each subject; this generalization was restricted to the type of imitation currently undergoing training. This development of a generalized imitation repertoire was observed in each subject. That is, these subjects imitated some responses that had never been specifically trained. More importantly, a training package consisting of prompting, fading, and consequences for delayed imitation functioned to develop generalized delayed imitation. These data exemplify a special case of generalization that was a function of the most recent training history of immediate or delayed imitation. The reversal design demonstrated that imitations of nontrained models were either delayed or immediate, depending upon which form of imitation was currently receiving training. Therefore, for each form of imitation trained, delayed or immediate, a corresponding response class was demonstrated. These data relate to data reported by Garcia, Baer, and Firestone (Journal of Applied Behavior Analysis, 1971, 4 , 101–112). The association lies in the proposition that there are identifiable boundaries of generalized imitation and that these boundaries are functionally related to previous training histories.     

THE EFFECTS OF CONTINGENT AND NONCONTINGENT REWARDS ON THE I.Q. SCORES OF CHILDREN OF ABOVE-AVERAGE INTELLIGENCE1

This study investigated the effects of candy reinforcement on I.Q. test scores in first and second graders of above-average intelligence. Thirty-six subjects were randomly assigned to one of three groups and either given candy contingent on correct responses, noncontingently, or not given candy. After measuring all subjects on Form L of the revised Stanford Binet, each subject in the contingent group was given an M & M immediately following each correct answer on Form M, while a yoked-comparison subject received the same number of M & M's before responding to a question and therefore without regard to correctness of answers. It was expected that both types of candy administration would produce higher I.Q. change scores than the no-candy control group, but there were no statistically significant differences among the three treatments. The differences between the first and second test scores were 4.17 (contingent), 4.67 (noncontingent), and 1.00 (no reinforcement). Reasons for this failure to replicate previous findings were discussed.     

CAPACITY AND DELAYED SPEECH

The experiment tests a hypothesis based on limited capacity under conditions of normal and delayed auditory feedback. Three predictions are tested on reading material in which syntax and coherent meaning are introduced as separate constraints. The hypothesis predicts that the difference between normal and delayed speech rates will be inversely related to the redundancy of the material but that the ratio of delayed/normal readings will remain constant across the passages since this measure also takes account of reading speed. A third measure, based on a selective analysis of speech disturbances, also confirms a prediction that the likelihood of speech disturbances increase throughout a sentence unit. The effects of delayed feedback are briefly discussed within the context of two recent models of information processing.     

MAINTAINING PERFORMANCE OF AUTISTIC CLIENTS IN COMMUNITY SETTINGS WITH DELAYED CONTINGENCIES

To facilitate the classroom and workshop integration of three autistic clients, we examined the feasibility of teaching them to respond appropriately without the continual presence of specially trained treatment providers. Within a multiple baseline design, a 4-step treatment process was implemented to promote durable responsive performance. Results indicated that the therapist could be removed from the treatment environment and that appropriate behavior could be successfully maintained in community settings with only infrequent and delayed contingencies.     

A COMPARISON OF SIMULTANEOUS AND DELAYED REINFORCEMENT AS TREATMENTS FOR FOOD SELECTIVITY

This study compared the relative efficacy of providing simultaneous or delayed reinforcement on food acceptance during meals. The participant was a 7-year-old boy with pervasive developmental disorder and a history of food selectivity. Results indicated that both procedures were effective in increasing acceptance; however, the simultaneous reinforcement procedure produced more rapid behavior change and a higher overall percentage of food acceptance.     

双耳分听和补笔对立即回忆延迟回忆影响的实验研究

通过两个实验探讨集中注意和补笔练习对立即回忆、延迟回忆的影响。实验一以英语单词为学习材料,使用组间设计方法,实验组采用附加追随程序和补笔练习;控制组为自定学习方式。学习结果表明：在自由回忆英文单词、听写英文单词和中译英三个方面,实验组的学习成绩明显高于控制组;实验组的学习方式更有利于低分组学生的学习。实验二的学习方式与实验一相同,通过４次测试的回归分析发现,实验组的学习发展水平明显高于控制组。     

ELEVATION OF VOICE VOLUME IN YOUNG DEVELOPMENT ALLY DELAYED CHILDREN VIA AN OPERANT SHAPING PROCEDURE

Unusually low voice volume was identified by teachers as a significant impediment to the academic and social progress of two preschool students. A simple operant shaping procedure was conducted by teachers to increase voice volume using a voice-activated apparatus with attractive visual display. Setting generalization of volume increases to the classroom was achieved and maintained at one- and four-month follow-ups.     

ERRORLESS LEARNING: REINFORCEMENT CONTINGENCIES AND STIMULUS CONTROL TRANSFER IN DELAYED PROMPTING

Delayed prompting can produce errorless discrimination learning. There is inherent in the procedure a disparity in reinforcement density which favors unprompted over prompted responses. We used three schedules of reinforcement to investigate the impact of reinforcement probability on transfer of stimulus control. One schedule of reinforcement was equal prior to and following a prompt (CRF/CRF), the second favored unprompted responses (CRF/FR3), and the third favored responses following the prompt (FR3/CRF). Experimental questions concerned the probability of errors, the probability of transfer, and the rate of transfer in the context of delayed prompting. Transfer was accelerated when reinforcement probability favored anticipatory responding. The schedule that favored prompted responses did not prevent a shift to unprompted responding. Errors were infrequent across procedures. Reinforcement probability contributes to but does not entirely determine transfer of stimulus control from a delayed prompt.     

EFFECTS OF IMMEDIATE AND DELAYED ERROR CORRECTION ON THE ACQUISITION AND MAINTENANCE OF SIGHT WORDS BY STUDENTS WITH DEVELOPMENTAL DISABILITIES

We compared immediate and delayed error correction during sight-word instruction with 5 students with developmental disabilities. Whole-word error correction immediately followed each error for words in the immediate condition. In the delayed condition, whole-word error correction was provided at the end of each session's three practice rounds. Immediate error correction was superior on each of the four dependent variables.     

RECREATING THE SCENE: AN EFFECTIVE WAY TO PROVIDE DELAYED PUNISHMENT FOR INAPPROPRIATE MOTOR BEHAVIOR

A mediated punishment procedure that involved recreating a behavioral sequence by guiding the subject through the behavior in the situation in which it occurred was used to suppress several severe problem behaviors in two developmentally delayed children. The mediational procedure was first used with a 4-year-old autistic boy for biting and then for foot stomping. Next the procedure was used for stealing and hoarding behavior with a multiply handicapped 17-year-old girl. Results indicated that the procedure was effective and produced relatively rapid results. One advantage of the procedure is that it provides an opportunity for trained personnel to apply restrictive procedures to low frequency behavior that occurs in their absence rather than relying on less qualified staff to implement the procedure immediately after the behavior occurs.     

MOVEMENT SUPPRESSION TIME-OUT FOR UNDESIRABLE BEHAVIOR IN PSYCHOTIC AND SEVERELY DEVELOP MENTALLY DELAYED CHILDREN

The effects of a movement suppression time-out, which involved punishing any movement or verbalization while a client is in the time-out area, were evaluated in four experiments. The first experiment examined the effects of a DRO procedure and movement suppression plus DRO in suppressing self-injurious behavior in a psychotic child in three different situations. In Experiment 2, the results of the previous experiment were replicated with two dangerous behaviors in a second psychotic child. In a third experiment, movement suppression plus DRO was compared with contingent restraint in reducing inappropriate poking behavior in two settings. The movement suppression procedure eliminated poking whereas contingent restraint had little effect. In the final experiment, movement suppression time-out alone was compared with exclusionary time-out alone and simple corner time-out alone. Self-stimulation occurred at high levels during the exclusionary and simple corner time-out procedures. Self-stimulation was either suppressed or reduced during movement suppression time-out. The movement suppression time-out procedure produced a larger reduction in the target behavior in all three children. The effectiveness of the movement suppression procedure was explained in terms of the suppression of self-stimulation while the time-out procedure was being applied.     

SPELLING AND EMERGENT PICTURE-PRINTED WORD RELATIONS ESTABLISHED WITH DELAYED IDENTITY MATCHING TO COMPLEX SAMPLES

Students with academic deficits learned delayed matching-to-sample tasks that used complex sample stimuli, each consisting of a picture and a printed word. A touch to the sample complex removed it from the computer display and produced either picture comparisons or a choice pool of letters. If the comparisons were pictures, selecting the picture identical to the preceding sample was reinforced. If the letters appeared, letter-by-letter construction of the preceding printed word sample was reinforced. The procedure engendered new constructed-response spelling performances and arbitrary relations among pictures and printed words in matching to sample. The emergence of relations among different sets of printed words (paired with the same pictures) suggested classes of equivalent stimuli. Outcome tests involving spoken words as sample stimuli suggested expansion of subjects' spelling repertoires and stimulus classes.     

THE CONTOURS OF AN EMERGING TERRITORY:IMPRESSIONS OF TWENTY YEARS OF ZYGON:JOURNAL OF RELIGION AND SCIENCE

Abstract. Abstract. While the general territory mapped by the founders ofthe Center for Advanced Study in Religion and Science and Zygonremains the same, how one delineates the contpurs of this territorydepends partly on personal histories and on whether one is atheologian, a scientist, a scholar of religious studies, or a philoso-pher. However, the pluralism in the CASIRAS-Zygon communitycan be placed in a more comprehensive, evolutionary framework, in which the different approaches exert cultural selection pres-sures on each other. The most important selection pressure ishaving to make scholarly work usable by nonscholars seekingmeaning for their lives in a scientific age.     

RULES OF EVIDENCE:

Abstract— Statistical tests define rules of evidence in psychological science Agreed-upon rules of evidence are needed to discuss what is true Statistics are probability statements about the reliability of associations In public and journalistic debates about psychological topics, the need far statistical rules is evident Anecdotes, intuitions, and sensational and unlikely events often dominate popular discussions Psychological science demands that the probability of events and associations be evaluated by statistical means Understanding of statistical tests can be improved by abandoning the term significance, winch means reliability to psychologists, but in everyday English, means importance. The importance of a result depends on magnitude of association, not on whether the event has a nonzero chance of recurring. Given large samples and multiple measures, statistical tests are used too often to draw misleading conclusions about the importance of research results. Better uses of statistics would focus on the magnitude of effects and error estimates     

ILLUSION OF CONTROL:

Abstract— Experiments in which subjects are asked to analytically assess response-outcome relationships have frequently yielded accurate judgments of response-outcome independence, but more naturalistically set experiments in which subjects are instructed to obtain the outcome have frequently yielded illusions of control. The present research tested the hypothesis that a differential probability of responding p (R), between these two traditions could be at the basis of these different results. Subjects received response-independent outcomes and were instructed either to obtain the outcome (naturalistic condition) or to behave scientifically in order to find out how much control over the outcome was possible (analytic condition). Subjects in the naturalistic condition tended to respond at almost every opportunity and developed a strong illusion of control. Subjects in the analytic condition maintained their p (R) at a point close to 5 and made accurate judgments of control. The illusion of control observed in the naturalistic condition appears to be a collateral effect of a high tendency to respond in subjects who are trying to obtain an outcome, this tendency to respond prevents them from learning that the outcome would have occurred with the same probability if they had not responded.     

CONCRETE TRANSITIVITY OF LENGTH: A METHOD OF ASSESSMENT

The problem of assessing concrete transitivity of length is explored with a non-verbal design employing nine sets of three sticks each. A training phase is used to establish the relevant variable to which the subjects must attend, to obtain a bead. A test phase consists of eight trials, in which the elements A, B, and C, are displayed in a systematic variation. A subject is said to display transitivity, when he more than five times in the eight trials chooses the largest of three sticks, A, on the basis of the information A > B and B 7< C. In a group of 20 children, varying in age between 52 and 80 months, half of the group, which is socio-economically upper-middle class, displayed transitivity. However, the youngest child displaying transitivity with six correct test-trials was 5 1/2 years old. The youngest child displaying transitivity with eight correct trials was 6 1/4 years old.