A comparison of measures of responding under fixed-interval schedules

Average response rate, post-reinforcement pause, elapsed time to the fourth response, average quarter-life, and running rate were examined to see how they reflected changes in fixed-interval performance. Rats were exposed to a mixed schedule of water presentation comprising fixed-interval schedules of two durations. Changes in responding were produced by varying the duration of the shorter component. The five measures were derived only from the longer schedule component. Post-reinforcement pause, elapsed time to the fourth response in the interval, and quarter-life all showed high, positive inter-correlations (0.78<r<0.99). Running rate and post-reinforcement pause were not as highly correlated. Quarter-life reliably reflected changes in fixed-interval performance but changes in the quarter-life value did not necessarily result from similar changes in fixed-interval response pattern. The two measures that adequately described changes in response patterning were post-reinforcement pause and running rate. These two measures also had the advantage of being simple both computationally and in terms of the instrumentation involved in their recording.     

Two types of empirical adequacy: a partial structures approach

The notion of empirical adequacy has received recent philosophical attention, especially within the framework of the semantic approach. Empirical adequacy, as explicated in the semantic approach, concerns the relationship between empirical substructures and some phenomena. The aim here is to differentiate this notion of empirical adequacy from one concerning the relationship between data and phenomena. Distinguishing each notion of empirical adequacy emphasizes different aspects of scientific practice—one concerning theory-development from the basis of an established theory, the other concerning theory-development from the basis of data-fitting, where established theory may not foster further development. To illustrate this contrast, an example from financial economics is considered.