Abstract
Three experiments on judgments of whether or not two stimuli moving are right angles to one another will collide are dealt with. Such judgments are common in everyday situations but the factors which determine them are poorly understood. The aim of the research was to provide information which eventually will be useful in auto driving. The report deals only with preliminary study on three specific questions: the rate of gain of information as a function of peripheral distance, the effect of differing number of brief information of a peripheral stimulus and the effect of visual angle on the moment the prediction is made.