If you're hoping for Cupid's online arrow, then watch out for tall stories and wide fabrications.

• Survey: Tried Online Dating?

A new study says online daters, both men and women, usually fib about either their height or weight, and sometimes their age.

Using a new method that measured the actual difference between profile information and reality, the study revealed that men systematically overestimated their height, while women more commonly underestimated their weight, said Jeffrey Hancock, an assistant professor of communication at Cornell University and the lead author on this study.

"Surprisingly, age-related deception was minimal and did not differ by gender," he said.

About 52.6 percent of the men in the study lied about their height, as did 39 percent of the women. Slightly more women lied about their weight (64.1 percent) than did men (60.5 percent). When it came to age, 24.3 percent of the men were untruthful, compared with 13.1 percent of the women.

Researchers examined four popular dating Web sites, where users create their own profiles and initiate contact with others: Match.com, Yahoo Personals, American Singles and Webdate, according to a press release. Study participants -- users of these Web sites -- were recruited in New York City through advertisements in the Village Voice and Craigslist.com. The final sample included 80 participants, equally divided between genders.

After collecting information about the participants from their online profiles, the researchers measured each person's height and weight, and obtained their age from drivers' licenses.

What constituted a lie? For height, the discrepancy had to be greater than half an inch; for weight, the deviation had to be greater than five pounds; and for age, there had to be a difference of a year. The results: A higher percentage of participants lied about their weight than either their height or age. In fact, for almost two thirds of the participants, weight was incorrect by 5 pounds or more.

Hancock said that social research abounds on how men and women use different strategies for finding love. In general, men seek youth and physical attractiveness in a partner, while women look for the ability to provide as well as indicators of social status, such as level of education and career.

The pattern of lies -- frequent but slight -- suggest that deception in online dating profiles is strategic.

"Participants balanced the tension between appearing as attractive as possible, while also being perceived as honest," Hancock said.

Since the study was completed, online dating sites have changed. They now inquire about general body types rather than request information on a person's specific weight, but the basic tension of trying to appear as attractive as possible without having a deception detected still applies, he said.

The study, by Hancock, Cornell doctoral student Catalina Toma, and Nicole Ellison, a Michigan State University assistant professor, will be published in an upcoming Proceedings of Computer/Human Interaction (April 2007), an annual peer-reviewed journal, to be released this spring during a Computer/Human Interaction conference in San Jose, Calif.