Want to know who your friends are? Just ask your cellphone, for a new study says that it can record the patterns of your relationships in impressive detail -- sometimes better than you can yourself.
According to the New Scientist, the finding of the study opens new possibilities for social scientists and others who want to know how people connect and interact socially.
For the study, an international team handed out mobile phones to 94 students at Massachusetts Institute of Technology -- the gadgets were modified with software which logged their calls, and used Bluetooth to detect when another was close by.
By looking for simple patterns in the logs of calls and times when phones were close together, researchers found they could predict who the volunteers would identify as their friends with 95 per cent accuracy.
The researchers were also able to link the phone data to the volunteers' satisfaction at work. Those who reported themselves less satisfied were less likely to have friends in close proximity and more likely to call friends during work.
The phones proved more accurate than the volunteers themselves at measuring how much time they spent physically near to others -- people typically overestimated how much time they spent close to friends and underestimated how much they spent with more casual contacts.
Although some of these findings may sound obvious, the study provides an important proof of principle -- the gadgets people carry day-to-day can accurately record the nuances of our relationships, the researchers from MIT and Santa Fe Institute in New Mexico said.
And, according to them, using cellphones for social science research could replace interviews, which are laborious and sometimes unreliable, to find out about people's lives.
The approach may also have immediately practical applications such as helping epidemiologists predict how swine flu will spread from person to person, suggested the study, which has been published in the latest edition of 'Proceedings of the National Academy of Sciences' journal.
