In this note, the Cramer-Rao lower bound of variance by using the two decks of cards in randomized response sampling has been developed. The lower bound of variance has been compared with the recent estimator proposed by Odumade and Singh at equal protection of respondents. A real practical...

In this paper, like a magician can show several birds flying out of an empty basket, we show that at least seven parameters of interest to a social scientist can be estimated from a single sample and one response from each respondent. A real survey data application is given.