Dear All I am looking for codes in FORTRAN or C to calculate the inverse normal CDF given a value p between zero and one. Any help would be grateful. Many thanks Shuying Yang Dr. Shuying Yang Tel: 0161-275-5192 Biostatistics Group Fax: 0161-275-5567 School of Epidemiology and Health Sciences University of Manchester Stopford Building Manchester M13 9PL Email:[log in to unmask] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%