Do the math: rape stats don't add up [Commentary]

You've heard the statistics: one in four women will be raped in college Or is it "sexually assaulted or almost sexually assaulted"? Or is it "nearly one in five"? Or "one in six"?

According to the White House, a rape epidemic is sweeping college campuses, with the #YesAllWomen campaign calling all men weapons of mass destruction.


Let's look at some facts.

According to the FBI "[t]he rate of forcible rapes in 2012 was estimated at 52.9 per 100,000 female inhabitants."


Assuming that all American women are uniformly at risk, this means the average American woman has a 0.0529 percent chance of being raped each year, or a 99.9471 percent chance of not being raped each year.  That means the probability the average American woman is never raped over a 50-year period is 97.4 percent (0.999471 raised to the power 50).  Over 4 years of college, it is 99.8 percent.

Thus the probability that an American woman is raped in her lifetime is 2.6 percent and in college 0.2 percent — 5 to 100 times less than the estimates broadcast by the media and public officials.

Of course, the rape-statistic apologists will say that rape is massively underreported.  Only 5 percent of the rapes or attempted rapes in a U.S. Department of Justice paper were reported to the police.  But why is that? Scholars Patricia Tjaden and Nancy Thoennes say that 17.7 percent of the women who did not file a report thought the rape was a "[m]inor incident; not a crime or police matter."

A 2013 Department of Justice report estimates that 64 percent of "rape and sexual assault victimizations against females" went unreported between 2005 and 2010, with 8 percent of women saying they did not report it because it was "[n]ot important enough," 7 percent saying they "[d]id not want to get offender in trouble with law," 13 percent calling it a "[p]ersonal matter," and 30 percent responding, "Other/unknown/not one most important reason."

Where does the "one in four" statistic come from? The organization One in Four USA cites a study by Ms. Tjaden and Ms. Thoennes, "Prevalence, Incidence, and Consequences of Violence against Women: Findings from the National Violence against Women Survey." If one looks at the 2006 report those authors published under the auspices of the Department of Justice, one finds that their results are based on a 1995-1996 telephone survey of 8,000 men and 8,000 women and that "only 24 women and 8 men reported during their interviews that they had been raped in the 12 months preceding the survey." That's an annual risk of 0.3 percent each year. This yields a 50-year risk of 13.9 percent, which is still significantly less than 25 percent.

The Ms. Magazine report, I Never Called It Rape, cites a survey of 930 women and concludes that 44 percent of them said they were victims of rape or attempted rape.  In defense of Ms., the actual study said that only 22 percent of the 930 respondents "disclosed experiences of completed and/or attempted rape in answer to the one question that used the word rape." The researcher, Diana Russell, doubled the figure.

The woman supervising the Ms. Magazine survey, Ellen Sweet, conceded that "1 in 4 or 5 women are the victims of rape or attempted rape, according to the legal definition, but only 1 in 4 of those women identifies her experience as rape." In other words, the real rape/attempted rape statistic is one-in-sixteen or one-in-20 — 5 percent.

Further exacerbating the confusion over rape statistics, the Department of Justice counts "verbal threats" as "sexual violence."  The Department of Justice report, "The Sexual Victimization of College Women" — which includes as victimization "general sexist remarks [made] in front of you" (grow a thick skin, girls) — says that 48.8 percent of the women who were raped said that what happened to them was not rape, with another 4.7 percent saying they didn't know if it was rape or not.  In other words, the rape researchers, and not the police, were the ones telling the purported victims, "I don't believe you."


To underscore this, I Never Called It Rape states in Chapter 4 that 42 percent of rape victims had sex again with their rapists.  The National Violence against Women study says that the average female victim was raped 2.9 times in the preceding year.  One infers that the "rape" victims were using a different definition of "rape" than the researchers.

As one University of Michigan student said two decades ago, "It makes a big difference if it's 1 in 3 or 1 in 50." Let's listen to college girls who can do the math.

Susan Patton is the author of "Marry Smart: Advice for Finding THE ONE." Her email is; Twitter: @ThePrincetonMom. Jonathan David Farley has been a visiting professor of mathematics at Caltech, a visiting associate professor of applied mathematics at MIT, a visiting scholar of the Department of Mathematics at Harvard University, and he is a math professor at Morgan State University. His email is

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