Estimating number of lifetime sexual partners: Men and women do it differently

On surveys, men report two to four times as many lifetime opposite-sex sexual partners (SPs) as women. However; these estimates should be equivalent because each new sexual partner for a man is also a new sexual partner for a woman. The source of this discrepancy was investigated in this study Participants reported number of lifetime and past-year SPs and estimation strategies. The pattern of lifetime estimates replicated. The lifetime protocols indicated that people used different estimation strategies that people who used the same strategy produced similar estimates, that some strategies were associated with large estimates and others with small ones, and that men were more likely to use the former and women the latter No sex differences in estimates or strategies were apparent irt the past-year protocols. Our findings suggest that discrepant lifetime partner reports occur because men and women rely on different estimation strategies, not because they intentionally misrepresent their sexual histories.