Iranian Institute of Industrial Engineering Journal of Industrial and Systems Engineering 1735-8272 1 1 2007 04 01 The Hypergeometric Coupon Collection Problem and its Dual 1 7 3913 EN Sheldon M. Ross Epstein Department of Industrial and Systems Engineering , University of Southern California, Los Angeles, CA, USA Journal Article 2006 04 01 Suppose an urn contains M balls, of different types, which are removed from the urn in a uniform random manner. In the hypergeometric coupon collection problem, we are interested in the set of balls that have been removed at the moment when at least one ball of each type has been removed. In its dual, we are interested in the set of removed balls at the first moment that this set contains all of the balls of at least one type. https://www.jise.ir/article_3913_b085c4fa543afe32970749f5e2bcdc6a.pdf