evaluate searching method Search speed How much storage space occupied Complexity of the algorithm ASL(Average Search Length): To ascertain the position of record in the table, and the expect number of key word comparing with the giving value To the table with n records ASL=>p,c, P, is the probability of the ith record in the table >P,=l C, is the number of keyword comparingevaluate searching method • Search speed • How much storage space occupied • Complexity of the algorithm • ASL(Average Search Length)： To ascertain the position of record in the table, and the expect number of keyword comparing with the giving value 1 1 1 = =   = = n i i n i i i p To the table with n records ASL p c is the probability of the ith record in the table i is the number of keyword comparing i c p