Choice: Some quantitative relations

Six pigeons responded in fifty-six conditions on a concurrent-chains procedure. Conditions included several with equal initial links and unequal terminal links, several with unequal initial links and equal terminal links, and several with both unequal initial and terminal links. Although the delay-reduction hypothesis accounted well for choice when the initial links were equal (mean deviation of .04), it fit the data poorly when the initial links were unequal (mean deviation of .18). A modification of the delay-reduction hypothesis, replacing the rates of reinforcement with the square roots of these rates, fit the data better than either the unmodified delay-reduction equation or Killeen's (1982) model. The modified delay-reduction equation was also consistent with data from prior studies using concurrent chains. The absolute rates of responding in each terminal link were well described by the same hyperbola (Herrnstein, 1970) that describes response rates on simple interval schedules.     

Performance of humans in concurrent avoidance/positive-reinforcement schedules

Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions.     

The Influence of Bloomfield's Linguistics on Skinner

Bloomfield''s “Linguistics as a Science” (1930/1970), Language (1933/1961), and “Language or Ideas?” (1936a/1970), and Skinner''s Verbal Behavior (1957) and Science and Human Behavior (1953) were analyzed in regard to their respective perspectives on science and scientific method, the verbal episode, meaning, and subject matter. Similarities between the two authors were found. In particular both asserted that (a) the study of language must be carried out through the methods of science; (b) the main function of language is to produce practical effects on the world through the mediation of a listener; and (c) a physicalist conception of meaning. Their differences concern the subject matter of their disciplines and their use of different models for the analysis of behavior. Bloomfield''s linguistics and Skinner''s functional analysis of verbal behavior are complementary approaches to language.     

Neuropsychiatric and experiential correlates of violent juvenile delinquency

This article reviews evidence regarding contributions of neuropsychiatric and psychological vulnerabilities to violent delinquency, and the interaction between intrinsic vulnerabilities and experiential factors in the genesis of antisocial juvenile behavior. Consideration is given to biochemical and physiological factors, genetics, medical status, and neurological, psychiatric, and neuropsychological factors. Implications for treatment are discussed.     

Behavior of humans in variable-interval schedules of reinforcement

During Phase I, human subjects pressed a button for monetary reinforcement in five variable-interval schedules, each of which specified a different frequency of reinforcement. The rate of responding was an increasing, negatively accelerated function of reinforcement frequency; the data conformed closely to Herrnstein's equation. During Phase II, the same five schedules were in operation, but in addition a concurrent variable-interval schedule (B) was introduced, responses on which were always reinforced at the same frequency. Response rate in component A increased while the response rate in B decreased, as a function of the reinforcement frequency in component A. Relative response rates in the two component schedules matched the relative frequencies of reinforcement. Comparing the absolute response rates in component A during Phase I and Phase II it was found that introduction of the concurrent schedule did not affect the value of the theoretical maximum response rate, but did increase the value of the reinforcement frequency needed to obtain any particular submaximal response rate.     

The Iatrogenic Effects of Group Intervention for Antisocial Youth: Premature Extrapolations?

Group intervention for antisocial youth has received harsh criticism in recent years. This paper reviews relevant research focused on the influence of contact with delinquent peers on the development of antisocial activity. Also reviewed are studies reporting outcomes of group intervention for antisocial youth. Although a few studies have found iatrogenic effects for group intervention with antisocial youth, the majority have not. Well-developed models of group intervention have produced substantial reductions in youth antisocial activity. We describe one such program, a family-style residential program based on behavioral learning principles, and review outcomes of this program. We conclude that treatment of antisocial youth in groups is feasible and can be effective in reducing delinquent behavior.     

Educating the Whole Child: Implications of Behaviorism as a Science of Meaning

New conceptions of what constitutes meaning for the organism have recently arisen within the behavioral tradition. These conceptions are a function of reformulations of traditional topics such as reinforcement and verbal behavior. This paper will review these reformulations and discuss their implications for education. It is argued that teachers are in need of a more comprehensive framework for understanding human behavior than the technique-based behaviorism to which they are frequently exposed. The present paper suggests that advances in our understanding of choice behavior and verbal behavior put us within reach of a comprehensive framework for making sense of the interconnectedness of social, self, and academic development.     

The relation between the generalized matching law and signal-detection theory

The generalized matching law can be applied to a signal-detection matrix to give two equations. The first relates responding in the presence of the stimulus to the reinforcements for the responses, and the second relates responding in the absence of the stimulus to the reinforcements for the responses. Evidence for stimulus discrimination is given by biases that are opposite in sign in the two equations. As the logarithmic ratio and z proportion transformations are similar, the combination of the absolute values of the two logarithmic biases gives a measure equivalent to the signal-detection measures d′ and η. The two equations can also be combined to eliminate the biases caused by the signalling stimuli and to produce a generalized matching-law statement relating overall performance to the obtained reinforcements.