The relation between response rates and reinforcement rates in a multiple schedule

In a multiple schedule, exteroceptive stimuli change when the reinforcement schedule is changed. Each performance in a multiple schedule may be considered concurrent with other behavior. Accordingly, two variable-interval schedules of reinforcement were arranged in a multiple schedule, and a third, common variable-interval schedule was programmed concurrently with each of the first two. A quantitative statement was derived that relates as a ratio the response rates for the first two (multiple) variable-interval schedules. The value of the ratio depends on the rates of reinforcement provided by those schedules and the reinforcement rate provided by the common variable-interval schedule. The following implications of the expression were evaluated in an experiment with pigeons: (a) if the reinforcement rates for the multiple variable-interval schedules are equal, then the ratio of response rates is unity at all reinforcement rates of the common schedule; (b) if the reinforcement rates for the multiple schedules are unequal, then the ratio of response rates increases as the reinforcement rate provided by the common schedule increases; (c) the limit of the ratio is equal to the ratio of the reinforcement rates. Satisfactory confirmation was obtained for the first two implications, but the third was left in doubt.     

Differentiation and decrement in the Mueller-Lyer illusion

Two experiments were conducted to test the hypothesis that decrement of the Mueller-Lyer illusion with inspection is due to learning to differentiate the test element from the accessory lines. In one experiment, the test element is predifferentiated for the observer by means of configurational variations and in the other by restriction of attention. Although the initial magnitude of the illusion is found to be inversely proportional to the amount of predifferentiation, the slopes of the decrement curves are not affected.     

Static visual noise and the ansbacher effect

In Experiment I subjects made estimates of the apparent length of a 12 cm. long light arc-line rotating around a central fixation point at arc speeds of 66, 99, 132 and 165 cm./sec. Apparent contraction of the arc occurred as a function of speed, there being greater contraction in the presence of a superimposed random pattern of I cm. light squares (visual noise) than in its absence. The results of Experiment II indicated that there was no significant difference in length due to visual noise when the arcs were stationary. In Experiment III subjects made estimates of the speed of rotation of the arc and it was found that visual noise did not significantly affect the apparent arc-speed.     

Retinal painting and visual information storage

As a measure of visual information storage (VIS), Haber and Nathanson (1968) have used a retinal painting task involving passing a narrow slit across a drawing which the S has to see as a single percept. Two experiments were conducted to evaluate this task as a measure of VIS. In experiment 1 it was shown that contrary to other measures of VIS, adults have longer values than children. In experiment 2 dyslexic and control children performed at equivalent levels on this task. It is suggested that retinal painting involves a different persistence effect to that normally used as a measure of VIS.     

Child abuse: Prognostic factors in therapy effectiveness

We have attempted to define the problem of child abuse by separating the abusers into two categories. Pattern abusers seem to be primarily a social issue in that the abuse is an outgrowth of the parental charge to control her/his child. However, another abuser is seen as a borderline or psychotic individual when the abuse is an outgrowth of a transferential distortion on the part of the parent. It was suggested that family therapy for the latter may be the preferential mode of intervention.     

Effects of inadmissible Evidence on the Decisions of Simulated Jurors: A Moral Dilemma

In a 2 × 3 design, simulated jurors received either weak or strong evidence against a defendant in a murder case. Within each evidence condition, subjects were given either additional evidence ruled admissible, additional evidence ruled inadmissible, or no additional evidence. Results indicated that ( a ) jurors were biased by inadmissible evidcnce in the weak-evidence but not in the strong-evidence condition, ( b ) strong evidence resulted in more guilty verdicts than did weak evidence, ( c ) confidence in verdict was influenced by strength of evidence, and ( d ) confidence of guilt was positively correlated with severity of punishment. Implications of the results are discussed within the context of the judicial process.     

The influence of the interaction of weight and volume on subjective heaviness

A model previously proposed for the size-weight illusion (Cross & Rotkin, 1975) was found unsatisfactory because the postulated volume parameter was not independent of the unit of measurement of weight and the model yielded a paradoxical prediction that the perceived heaviness of small objects should decrease as their weight increased. A new model was proposed based on Stevens and Rubin’s (1970) finding that heaviness functions are a family of con-verging power functions and some of Cross and Rotkin’s developments. The model was ex-amined by estimating its parameters from data previously reported by Cross and Rotkin, Stevens and Rubin, and Kolehmainen and Mikkonen (1970). The equations was found to fit each set of data well. Four independent estimates of a volume parameter of the model were in close agreement, .18, .21, .21, and .24, which is consistent with the model. nt]mis|This research was supported by Grants A0151 and A9582 from the National Research Council of Canada.     

The nature of equity-restoration: Some approval-seeking considerations

Subjects performed a proofreading task and evaluated its difficulty both beforehand and afterwards. They were overpaid or equitably paid by an experimenter who was or was not directly responsible for the level of pay they received, and who they believed would or would not see their post-test ratings. All subjects knew the experimenter would grade their task performance. Consistent with equity theory, overpaid subjects rated the task as having been more difficult than they had expected and did higher quality work than did equitably paid subjects. However, subjects who thought the experimenter would see their ratings (Aware condition) rated it as more difficult and performed more poorly on it than those who thought she would not see them (Unaware condition). Reported task difficulty increased among overpaid subjects under aware conditions, remained stable among overpaid subjects under unaware conditions, and decreased for equitably paid subjects. These findings suggested that what appears to be “equity-restoration” may be a self-presentation strategy designed to win the experimenter's approval, and that task ratings rather than performance will be used for this purpose when they can be communicated to the experimenter. The experimenter's responsibility for the subject's pay had no effect in the present study.