The effect of sequential dependencies on some signal detection parameters

The values of various sensitivity and response criterion parameters were calculated under different experimental conditions for both detection and recognition tasks. The effects of feedback and stimulus probability were found to be consistent with previous studies. When the values of the parameters were computed depending on the nature of the immediately preceding trial, the criterion parameters were found to be dependent on the identity of the preceding response, while those measuring sensitivity were dependent on its correctness. The dependence of the sensitivity parameters could be explained as an artifact of statistical bias, while the effect on the criterion parameters appears genuine. The nature of the phenomenon of statistical bias is discussed.