reaction time of traffic signal design the new york state departement of transportation is conduction an expriment to estimate the safe stopping distance on a stop light at a busy crossroad.in this human factor experiment ,the reactiontime of human subjects are measures as the elapsed time from the instant stop light is displayed until the subject hits thebreaks ,two people are involved in one of the experiments where the times are measured in second for each person (t1,t2) venn diagram of events E1,E2 and E3 E1: Divide[t1+t2,2]0.15 , E2:max(t1,t2)0.15 , E3:Abs[t1-t2]0.06