MINIMUM-COST SINGLE AND DOUBLE SCREENING PROCEDURES WITH DICHOTOMOUS PERFORMANCE VARIABLE

Minimum cost single and double screening procedures are presented base d on two screening variables (X(1),X(2)) as a substitute for one dicho tomous performance variable T (conforming/nonconforming). It is assume d that X(1) and X(2) are highly correlated with T and relatively inexp ensive to measure compared to T. It is also assumed that X(1) and X(2) given T are normally distributed. Two screening variables are observe d simultaneously in the single screening procedure and sequentially in the double screening procedure. Cost model are constructed which invo lve the two screening inspection costs and costs of misclassification errors. Methods of finding the optimal cutoff values of the screening variables are presented. An illustrative example is given and numerica l studies are performed to compare the proposed screening procedures b ased on two screening variables with the screening procedures based on one screening variable.