An alternative randomized response model using two deck of cards: a rejoinder

Abstract

The Randomized response (RR) technique with two decks of cards proposed by Odumade and Singh (2009) can always be made more efficient than the RR techniques proposed by Warner (1965), Mangat and Singh (1990), and Mangat (1994) by adjusting the proportion of cards in the decks. Abdelfatah et al. (2011) modified Odumade and Singh (2009) RR technique and claimed that their method can be more efficient than the Warner (1965) model. In this paper it is shown that such claim is not valid and the RR technique proposed by Abdelfatah et al. (2011) is in fact less efficient than the Warner (1965) technique at equal protection of respondents. Such finding are recently shown by Giordano and Perri (2011).