Olga Khazan: Speaking of porn, I was wondering if you could talk about pornography featuring violence against women. What's surprising about who looks for that, and what might that tell us?

Seth Stephens-Davidowitz: It’s a big theme of pornography, but I think the somewhat surprising thing is that it’s far more popular among women than men. It’s one of the most popular genres of pornography for women. Just about every search that is looking for violent porn is roughly twice as common among women than men.

Of course the danger is that somehow people will hear this and they’ll think that somehow this makes rape a less horrific crime, which it doesn’t. It’s just a fantasy, of course it doesn’t mean that they want that in real life.

Khazan: To me that suggested that there’s a really big distinction between fantasy life and real life, as far as people's sexual desires.

Stephens-Davidowitz: Well it’s kind of similar also to horror movies, which are also [popular] among women. I don't think women want to be kidnapped in real life, but many women enjoy watching movies featuring kidnappings.

Women also search for a lot of lesbian porn, even women who do not consider themselves lesbians.

Khazan: So let’s say you stop watching porn and actually go on a date with someone. How can a man tell if a woman is interested in him, and vice-versa?

Stephens-Davidowitz: This is a study where researchers gave tape recorders to men and women, heterosexual men and women, who are on speed dates. Then they measured whether the men and women wanted to go on a second date. Then they said: What words do men and women use on first dates that suggest that they want to go on a second date, or that can improve the chances that a partner wants to go on a second date?

For the women, a woman frequently signals interest by talking about herself using the word “I” a lot. A man signals interest by talking in a deep monotone voice. A woman signals disinterest by using hedge words, such as “sort of,” “kind of,” or “probably.” A man can increase the odds of a woman wanting a second date by laughing at her jokes or showing support, such as saying “that must have been difficult” or “that sounds tough.”

Of course that's not rocket science, but I think a lot of men probably still need to read it. A woman can increase the odds of a man wanting a second date by talking about herself a lot, by using the word “I.” That kind of goes against conventional wisdom. I think a lot of women think that they shouldn't talk too much about themselves. But, men seem to like when a woman opens up on a first date.

Khazan: Alright, and once they’ve been dating a while … what's the number one search complaint about boyfriends?

Stephens-Davidowitz: That my boyfriend won't have sex with me.

Khazan: You said that's more common than “my girlfriend won't have sex with me,” right?