A study has suggested that surveys of cyber crime and numbers of sexual partners have a lot in common, as both are subject to "catastrophic errors".
The analysis by a Microsoft research team said both are self-reporting, and uncorroborated surveys, hence not reliable.
Dinei Florencio and Cormac Herley said in a paper entitled 'Sex, Lies and Cyber Crime Surveys', that there were deep similarities between surveys that try to get a snapshot of hi-tech crime and those that peep into human sexual relations.
In the case of sexual partner surveys, such self-reporting produces totals, which suggest that men have had far more female sexual partners than women have had male sexual partners.
This, according to the researchers, "is impossible".
The truth is that in these surveys men over-report partner numbers and women under-report. Plus, said the researchers, some men tell "whopping" lies about their sexual lives and, as a result, vastly inflate the final results.
The same is true of cyber crime surveys, in that respondents tend to over-report.
Mathematical analysis of the surveys shows that it only takes a few large overestimates to produce a total that bears little relation to the facts.
"Our assessment of the quality of cyber crime surveys is harsh. They are so compromised and biased that no faith whatever can be placed in their findings," the BBC quoted the researchers as writing.
The Sex Lies and Cyber Crime surveys paper is due to be presented at the forthcoming Workshop on the Economics of Information Security.