Thanks for the link to the research document. Without trying to sound too critical of that paper and its author, it really isn't much of a research paper, and it is so confusing that it's easy for anyone reading it to be misled. I too was misled when I found some table indicating that 100% of serial killers are male. That simply is far from the truth. The link below offers some more verifiable information about the percentage comparisons. Apparently, about 80% of all serial killers are male, and 20% are female. It's an interesting little article. Serial Killer Myth #3: They Are All Men Cheers.