My colleague and friend Bob Levey invited me to be on his radio show on WBAL in Baltimore last Saturday, and at one point on the show I cited a conservative statistic I'd seen that one in four women can expect to be raped in her lifetime.

Within minutes, two men were on the phone to Levey to say they didn't believe that statistic. One said he knew at least 50 women well and none of them had been raped. "They're not going to tell you," Levey said. I said the same thing. But there is more to it than that.

Rape is one of the most underreported crimes. But compounding the problem of measuring its incidence is the way women are asked questions about it in law enforcement surveys. What is clear, and what was so striking about the men's phone calls, is that women as well as men are still going through a heavy siege of denial about the extent to which men are forcing women to have sex against their will. That is the legal definition of rape.

"In 50 to 75 percent of all rapes, the victim knows her attacker," says Bernice Sandler, executive director of the Project on the Status and Education of Women. "Women are more vulnerable to the acquaintance rape than stranger rape." Sandler, whose research into campus date rape propelled that crime into the national conscience, said that surveys of college women find that between 15 and 25 percent of them have been raped by the time they are in college. "Many of the women do not label their experience as rape. They are still thinking of rape as something that happens in dark alleys with a stranger. The same is true of men. If you ask them if they have ever raped anybody, a lot will say no. If you ask have you ever forced or intimidated someone to have sexual intercourse between 10 and 15 percent in most of the studies will say yes."

She cites a study done by a professor of criminal justice at the University of Nebraska who has asked his students if they have ever committed such illegal acts as armed robbery or forced sex. In 1985, 11.7 percent of the women said they had been forced to have sex against their will. By 1988 that figure had soared to 29.3 percent. The number of men reporting they had forced a woman to have sex rose from 5.1 percent to 12.7 percent. "To the extent that other forms of violence are increasing in society, one should not be surprised that rape is increasing too," Sandler said.

I told Sandler about the man who didn't know any woman who had been raped. "They don't tell him," she said. "When I was growing up, before the women's movement, nobody said the word rape in mixed company at all. When a woman was raped, you'd say attacked. The rape crisis centers to this day get calls from women who say I was raped 20, 30, 40 years ago and you are the first person I've ever told. We live in a society in which women are seen as responsible for men's sexuality and they blame themselves very often. It is the women's movement that has brought rape out into the open and has labeled acquaintance rape as violence."

Denise Snyder, director of the D.C. Rape Crisis Center, uses the statistic that one out of every three women can be expected to be raped in her lifetime. Her source is Diane Russell, a sociologist in California who wrote the book "Sexual Exploitation." Her study, done in the late 1970s, found that 44 percent of the women surveyed had been the victim of attempted rape or rape, and 33 percent had been raped.

"The Uniform Crime Statistics reports are much lower because in those studies they almost always start by asking have you ever been the victim of a violent crime. A lot of rape survivors will answer in the negative to that question, particularly in an acquaintance rape situation." But when the woman is asked have you ever had sexual intercourse against your will, was forced used or the threat of force -- which is the key in the legal definition -- the studies yield far higher rate of rape, she says.

"We get calls here all the time from women who will describe a rape, but they can't put that label on it.

"There's an element of denial for women. Part of it is a self-defense mechanism." Admitting to being raped by an acquaintance, "drastically affects my ability to trust my own instincts" about whom to trust, says Snyder.

"For men, and women, when you start to recognize that one in three women will be raped you have to face the reality that men who are doing the raping are not a small psychotic part of the population. There are a lot of men out there who we look at as sort of mainstream men who have raped. And that's what nobody wants to see. Women don't want to look at it, and men don't want to look at it. That's why people get angry when you say one out of three of us are going to be raped."