More people have ventured into the potentially hazardous¹ waters of online dating than would care to admit - and some of their adventures have been truly hair-raising.

很多人会大胆尝试网上约会这一存在潜在危险的事情而不愿承认，而且其中一些人的网上约会经历还相当耸人听闻。

Now a group of former Harvard math majors are crunching² the data to reveal the secret tips of the online dater, displaying them in - naturally - graph form.

Men, for example, should show off their six pack if they have one - but only if they're young. Meanwhile women should always flirt³ with the camera - but men should look aloof⁴（冷淡的） .

The OkTrends blog found at dating website OkCupid have been charting various trends - such as how long relationships last among Twitter users - since 2009.

One of the blog's tips is to ask your date if they've ever wanted to run away to sea, whether they enjoyed the Blair Witch Project, or their past travel experiences.

The reasoning, the bloggers explained, was that according to the thousands of multiple choice 'match questions' answered by OkCupid's seven million users, couples who met on the site agreed most often on three questions in particular: 'Do you like horror movies?', 'Have you ever travelled around another country alone?', and 'Wouldn't it be fun to chuck it all and go live on a sailboat?'

Experts told the LATimes that these types of questions are measuring the 'openness to experience' or the O Factor.

'People who seek stimulation⁵ and adventure... they'd be less likely to establish and comfortably maintain a relationship with very traditional, conservative, unimaginative（缺乏想象力的） , risk-avoidant individuals,' said Western Carolina psychology⁶ department head David McCord.

Women were also told to flirty⁷ with the camera for their profile photo. If they made what OkCupid called 'flirty-face', they received on average 1.5 additional messages per month.

That's because a woman's smile is well-documented as a signal of sexual interest. 'Flirty smiles trigger what we call men's sexual over-perception bias⁸（偏见） ,' Dr Buss said.

Only, however, for women. Men were ordered to be aloof on camera. When they did so, they had a roughly 90 per cent success rate with their emails than otherwise.

The data also showed that women who took their 'flirty-face' to the next level by showing a bit of cleavage had better results - vastly better results as they got older. For men, the inverse⁹ is true. Male online daters should show off their six packs in their profile pictures, but only if they are young.