The secretary problem

In many spheres of activity, decisions must often be made under uncertain conditions. One such problem relates to selecting a candidate from a known number when: (a) candidates arrive in a sequence; (b) the selection process has to decide on a candidate then and there; (c) the process terminates if a candidate is selected; (d) the process continues if the candidate is not selected. The question is: What is the strategy that maximises the probability of selecting the best candidate? How does one use the ‘scores’ of each of the candidates seen so far to decide if the present candidate must be selected or if the process be continued, in the quest for the best candidate? This is the problem ofoptimal stopping, an example of which is discussed here.