Affiliations: Department of Mathematics, Statistics & Physics, Punjab Agricultural University, Ludhiana-141 004 (Pb), India
Abstract: In this paper two improved randomization devices RD-I and RD-II are proposed which consist of pack of cards having three types of statements written on it and on each card there is only one statement. A comparison of proposed devices is made with the existing Greenberg et al.  model which shows that the proposed randomization devices are better. A comparison within the proposed randomization devices has also been undertaken which shows that the RD-I is better than RD-II.