On the limits of the matching concept in monkeys (Cebus apella).

Two cebus monkeys, with many years of experience matching a variety of static visual stimuli (forms and colors) within a standard matching-to-sample paradigm, were trained to press a left lever when a pair of displayed static stimuli were the same and to press a right lever when they were different. After learning the same/different task, the monkeys were tested for transfer to dynamic visual stimuli (flashing versus steady green disks), with which they had no previous experience. Both failed to transfer to the dynamic stimuli. A third monkey, also with massive past experience matching static visual stimuli, was tested for transfer to the dynamic stimuli within our standard matching paradigm, and it, too, failed. All 3 subjects were unable to reach a moderate acquisition criterion despite as many as 52 sessions of training with the dynamic stimuli. These results provide further evidence that, in monkeys, the matching (or identity) concept has a very limited reach; they consequently do not support the view held by some theorists that an abstract matching concept based on physical similarity is a general endowment of animals.     

Timing multimodal events in pigeons

The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made.     

The operant conditioning of response variability: Free-operant versus discrete-response procedures

The operant conditioning of response variability under free-operant and discrete-response procedures was investigated. Two pigeons received food only if their pattern of four pecks on two response keys differed from the patterns emitted on the two immediately preceding trials. Under the free-operant procedure, the keys remained illuminated and operative throughout each trial. There was little variability in the response patterns that resulted, and the pigeons received fewer than one third of the available reinforcers. Under the discrete-response procedure, a brief timeout period followed each response. Variability increased under this procedure, and the pigeons obtained three fourths of the available reinforcers. Previous successes and failures to produce response variability may have been due to the use or failure to use, respectively, a discrete-response procedure. Respondent effects inherent in the free-operant procedure may encourage the development of response stereotypy and, in turn, prevent the development of response variability.     

Choice between delayed reinforcers and fixed-ratio schedules requiring forceful responding.

This experiment measured pigeons' choices between delayed reinforcers and fixed-ratio schedules in which a force of approximately 0.48 N was needed to operate the response key. In ratio-delay conditions, subjects chose between a fixed-ratio schedule and an adjusting delay. The delay was increased or decreased several times a session in order to estimate an indifference point--a delay duration at which the two alternatives were chosen about equally often. Each ratio-delay condition was followed by a delay-delay condition in which subjects chose between the adjusting delay and a variable-time schedule, with the components of this schedule selected to match the ratio completion times of the preceding ratio-delay condition. The adjusting delays at the indifference point were longer when the alternative was a fixed-ratio schedule than when it was a matched variable-time schedule, which indicated a preference for the matched variable-time schedules over the fixed-ratio schedules. This preference increased in a nonlinear manner with increasing ratio size. This nonlinearity was inconsistent with a theory that states that indifference points for both time and ratio schedules can be predicted by multiplying the choice response-reinforcer intervals of the two types of schedules by different multiplicative constants. Two other theories, which predict nonlinear increases in preference for the matched variable-time schedules, are discussed.     

Infinite Set Unification with Application to Categorial Grammar

In this paper the notion of unifier is extended to the infinite set case. The proof of existence of the most general unifier of any infinite, unifiable set of types (terms) is presented. Learning procedure, based on infinite set unification, is described.     

Teaching spontaneous requests to children with autism using a time delay procedure with multi-component toys

Children with autism were taught spontaneous requests through a time delay procedure. Unlike previous research, which usually employed food as the target stimuli to be requested, the present study used toy pieces from multi-component toys. The procedure involved presenting a child with the target stimulus, with the trainer prompting the child by immediately modeling the request response. When the response was imitated without error, prompting was delayed with the time interval gradually being increased over trials. A spontaneous or imitated response was reinforced by giving the child the requested object. As the stimulus/model interval increased, children with autism were expected to initiate the request by themselves prior to the prompt. The efficacy of the time delay procedure was assessed using a multiple baseline across subject design with three Chinese boys with autism. Results showed that the three children acquired a 100% performance within five to nine sessions of training and the skill was maintained at the one-month and three-month followups. Furthermore, the learned response transferred to various conditions when tested across setting, person, toy, and food items. These results suggest that toys, the multi-component ones in particular, served well as reinforcers for language training. Furthermore these findings confirmed the practical utility of the time delay procedure for promoting spontaneous communication skills in children with autism.     

Consequence analysis: Its effects on verbal statements about an environmental project

Typically, citizens lack relevant information concerning possible consequences of proposed environmental projects. Despite federal requirements for citizen participation in decisions about proposed roadway projects, no systematic procedures exist for educating citizens as to the possible consequences of such projects. The effects of a consequence analysis procedure on community residents' verbal statements about the favorability of a proposed roadway project were assessed. The consequence analysis procedure involved asking residents to rate the desirability and magnitude of each of 48 possible consequences of the proposed roadway project. Following the intervention, overall ratings of favorability of the project changed for nine of ten residents. Community residents' ratings of the quality of participants' justifications of their position on the roadway issue provided evidence of generalization to this collateral behavior.     

Using the teaching interaction procedure to train interventionists to implement the Cool versus Not CoolTM procedure

The teaching interaction procedure is a behavior analytic procedure that has been used to target the development of social skills. The teaching interaction procedure consists of labeling the target skill, providing a meaningful rationale, describing the steps of the target skill, modeling the skill, role‐play, and providing feedback throughout the interaction. Although the teaching interaction procedure has been used to teach a variety of social skills for individuals diagnosed with autism spectrum disorder (ASD), it has only been used to train staff in two studies. The purpose of this study was to evaluate the use of the teaching interaction procedure to teach three interventionists to implement the Cool versus Not Cool? procedure to target the development of social skills for children diagnosed with ASD. The results of a multiple baseline design demonstrated that the teaching interaction procedure was effective for all three interventionists. Results of the child participants' skill acquisition are also provided.     

A multi-objective mathematical programming problem with fuzzy relation constraints

In this study we discuss the problem of multi-objective mathematical programming with constraints defined by ‘max-min’ composite fuzzy relation equations. Since the feasible region is normally non-convex, the properties of the efficient points of a non-convex feasible region under multi-objectives are investigated and illustrated by examples. The necessary and sufficient conditions are proposed and proved. To facilitate decisions, a procedure that transforms these efficient points of an interval-valued decision space into a constant-valued decision space is proposed when the level of confidence is given by a decision maker. Then the transformed problem becomes a multi-attribute decision problem that can be evaluated by Yager's method to find the optimal alternative.