Question

15-10. Suppose we want to investigate the percentage of abused children in a certain population. To do this, doc tors examine some of these children taken at random from that population. However, doctors are not perfect: They sometimes classify an abused child (A) as one not abused (D or they classify a nonabused child (A) as one that is abused (D). Suppose these error rates are Pl DIA*) 0.08 and P(D+ | A")-0.05, respectively; thus, PD 1A) 0.92 and PD IA-0.95 are the probabilities of the correct decisions. Let us pretend that only 2% of all children are abused: that is, P(A+) 0.02 and P(A) 0.98

Answer 1