A DESIGN AND MODEL FOR ESTIMATING EFFECTS OF ONE TRIAL ON NEXT IN A SEQUENCE HAVING 2 TYPES OF TRIAL

A statistical design and model is presented for estimating the after‐effects of the treatment given at trial n on trial n + 1, when there are two kinds of treatment in a series. The specific application of the model is to an evaluation of the effects of stimulation produced by reward and non‐reward in a partial reinforcement situation. A rationale for the model is provided; the derivation of the estimates and the analysis of variance is described; and the model is applied to the analysis of some data which form part of a study published elsewhere. The results of the analysis indicate that reward and non‐reward affect immediately following performance differentially at 20 sec. intertrial intervals but not at 12 min. intertrial intervals. 1969 The British Psychological Society