Albert Erlebacher

Response frequency equalization: A bias model for psychophysics

A model for response bias in psychophysics is derived. Of the model’s two aspects, one is concerned with the generation of sensory states and the other with rules for transforming sensory states into responses. The model incorporates the bias rule that Ss tend to use available responses with equal frequency. Applications to experiments which use the method of constant stimuli are discussed. Despite the contrary claims of Restle and Levison (1971), the model not only predicts their data quite well but also, under certain conditions, does so better than the theory of adaptation level used by Restle and Levison themselves.

The invalidity of “invalid results from the method of constant stimuli”: A common artifact in the methods of psychophysics

A description by Levison and Restle (1968) of deficiencies in the method of constant stimuli is shown to be logically in error. Their data, as well as those from other experiments, are interpretable in terms of a response bias that may distort data in a variety of psychophysical studies. This bias is the tendency of Ss to use available responseswith equal frequency.

The analysis of multifactor experiments designed to contrast the within- and between-subjects manipulation of the independent variables

Experiments are frequently performed in which the major question of interest is whether the effect of the substantive independent variable depends on its manipulation within as opposed to between subjects. Erlebacher (1977) discussed the design of such experiments in which one independent variable is manipulated, and presented a method of analysis by an analysis of variance technique. This paper discusses the analysis of three different experimental designs in which the within-subjects/between-subjects design type is one factor and two substantive independent variables are manipulated. A rule is also presented that can be used to generate statistical tests in a generalized multifactor design.

Differential accrual of frequency in verbal-discrimination learning

The notion that Ss build up a different number of frequency units for correct and incorrect items of a verbal-discrimination task was tested. Following verbal-discrimination learning, Ss were given a recognition retention test. It was found that they correctly identified more of the correct than incorrect members of pairs. This is in support of the tested notion.

Differential GSR conditioning with a complex CS

As a first step in the investigation of the effect of stimulus information on differential conditioning, the present experiment was performed using geometrical figures with one relevant and one irrelevant bit of information as CSs. Differential conditioning was indeed possible. Furthermore, conditioning was rapid, indicating the influence of concept formation or language. The effect of several control variables was also studied. These had minimal influence on conditioning.