HERRNSTEINS EQUATION - DATA FROM 110 RATS

110 rats were trained under a series of variable-interval schedules of sucrose reinforcement (0.6 M, 50 mu l), covering a wide range of sche duled interreinforcement intervals. Response and reinforcement rates r ecorded during the last five sessions of exposure to each schedule wer e used to fit Herrnstein's (1970) hyperbolic 'response strength' equat ion to the data from each rat. The equation accounted for >80% of the data variance in 90%, and >90% of the variance in 6O% of the sample. T he distribution of the values of R(max), the asymptote of the hyperbol ic curve, did not depart significantly from normality. However, the di stribution of the values of K-H, the reinforcement rate needed to main tain the half-maximum response rate, was markedly skewed; logarithmica lly transformed values of K-H conformed to a normal distribution. The data provide further support for the applicability of Herrnstein's equ ation to variable-interval performance; it is suggested that studies i nvolving comparison of the parameters of the equation between groups o f subjects should adopt logarithmic transformation of the values of K- H.