The randomized response survey model introduced in 1965 by Warner is r
eviewed and applied to the analysis of contaminated data, that is, res
ponse or reported data that is truthful with probability less than one
. Two generic mechanisms are distinguished: an active mechanism whereb
y the contamination is inserted into the process and hence becomes a s
tatistical design parameter, and a passive mechanism whereby contamina
tion of the response is suspected and hence becomes an analysis parame
ter. The impact of contamination on the operating characteristics of s
ome common statistical inference procedures is developed for binomial
models.