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Page last updated at 01:14 GMT, Tuesday, 27 November 2007

Love plus one

Ruth Alexander

The new generation of dating services claim their huge data sets and secret algorithms can find customers the perfect match. How do these work? BBC Radio 4's More or Less reporter Ruth Alexander explains.

Some might pin their hopes on a chance encounter or eyes meeting across a crowded room. But I'm taking a more evidence-based approach to love. I've signed up with an online dating agency which uses complex mathematical equations to analyse your personality and tell you who you ought to go out with.

It's one of several websites which say their match-making methods are scientific and proven to create the happiest of relationships.

First of all, the website invites me to answer a long questionnaire. How much reassurance do I need from a partner? How much do I give to charity? How tidy is my home?

Ruth Alexander
The bow-tie and waistcoat had gone, and my date was tall, dark and more handsome than his photo had suggested
Ruth Alexander
"The majority of questions represent statements commonly heard by therapists in couples counselling," says psychologist, Dr Garth Bellah.

The website then uses what statisticians call a regression equation to determine what sort of person I would be best matched with, according to my character and how that fits with historical data about other people's relationships.

The company says it's identified 99 distinct factors found in successful relationships. Another dating site says there are 29 - its mathematical match-making is based on research it says it's done on 10,000 married couples.

Looking at the profiles of the men the computer highlighted for me, I was highly sceptical, bordering on horrified. But I gritted my teeth and sent a flurry of e-mails: would you like to go on a date with me and my microphone?

It turns out the compatibility test doesn't yet measure aversion to journalists. Only two people e-mailed back - and one of those dumped me for someone else before we'd even met.

Crowd wisdom

So I was left with one chance of love. And he was wearing a burgundy bow-tie and waistcoat. But our compatibility score was 94%. The computer said yes.

"Don't know much about algebra..."

How can a computer know more about me than me? Author of Super Crunchers, Ian Ayres, says such sites "represent a new wisdom of the crowd - where if you aggregate the predictions of hundreds of people you can do a better job of prediction - because they're unlocking the wisdom that is hidden within thousands of pieces of historical data.

"You're still extracting information from the crowd, but you're finding stuff that individuals would never have been able to figure out themselves."

By the time, I alighted the train in Guildford, my legs had gone shaky. But the bow-tie and waistcoat had gone, and my date was tall, dark and more handsome than his photo had suggested.

8pm: Off to the pub. By the time we'd ordered drinks and sat down, conversation had ranged from the weather through to the Russian language. He was easy to talk to; I was impressed. But was this maths making the match?

I'd done some preparation before the date, having been to see psychologist Dr Viren Swami. When I told him an algorithm was going to find me love, he was unimpressed.

Physical attraction

"There was famous study in the 1960s, which invited participants to take part in a dating programme," says Dr Swami, of the University of Westminster. "They were told they would be matched by a super computer according to personality and values.

Slide rule
"...don't know what a slide rule is for"

The experimenters found the best predictor of relationship initiation was not in fact things like similarity, personality or values, but similarity of physical attraction. But there was also an effect of expectancy: people who believed the computer was really doing something wonderful were more likely to make an effort with their potential partner."

The dating websites which use these equations of love promise great things. One of them says 90 of its members get married to each other every day. But what proportion of its members does that represent? It won't say.

What's more, the sites disagree about what compatibility is. The one I'm trying says complementary types work best together. Another says people who are similar make the best match.

9pm: my date and I like each other enough to start insulting each other. London-types have a reputation, he tells me. Judging by my photo, he'd assumed I was going to be "wine bars only". I admit I had thought he would be posh and bumbling.

Number crunching

10.15pm: I'll be in touch, I say. But on the train home, a thought occurs to me. Where was the chemistry? That mysterious quality that eludes even the most complex of dating algorithms.

Figures are all very fine, but what about them chemistry?

"People still have to see if that spark's there," says Dr Galen Buckwalter, from dating agency eHarmony.

"We don't measure things like chemistry. But we give people information on long-term personality traits and the fact that their match meets the criteria identified by extensive research - and that's very important information".

But doesn't this hard-headed number-crunching ultimately take the romance out of romance?

Author Ian Ayres: "If we're really going to do a super-crunching approach to this we'd want to know how much chemistry there is on your average date - really you'd want to compare it to a blind date your close friend set you up on."

Could it be me, and not the equation, that's a damp squib?

He added: "If you have the image that the only true romance is where you literally knock into someone while you're walking down the street that, I think, is a recipe for disaster."

Maybe so, but I don't think there will be a second date. And there was something slightly irritating about having a computer deciding what I was like and who I should fancy. I know my single status shows a lack of past judgement, but I'm not ready to give up on my own mind yet.

You can download More or Less here or hear it on Radio 4's Listen Again site.

Below is a selection of your comments.

I met my partner through an on line dating agency (3 years ago last September)and before that went out with others whom, whilst there may not have been the special spark, were great company. The fact that we had seen photographs, exchanged emails and telephone conversations meant there was far more success than meeting someone for an hour in a bar or club and then arranging to meet. Trouble is if there is too much chemistry on first meeting it's easy to ignore all the things that are wrong!
sandra culham, Colchester

I met my husband almost 40 years ago on a blind date, although for me, it wasn't blind as I had seen this very sexy bloke pass me at my bus stop and I arranged for a mutual friend to set up a blind date. Physical attraction plays an enormous part at the start of any new relationship; we talked all evevning non stop and we both knew we were very attracted to one another. Computers can only do so much; for gods sake allow nature to do the chemistry!We are soon to retire; had two boys and have two grandchildren. The secret of this great relationship?Big sexual attraction; similar backgrounds and an ability to listen, and apologise when necessary.
sue knill, Wilts

I seriously doubt that Ms. Alexander has any difficulty in catching the eye of the male population.
Martin, London

I had to laugh at this story. It proves the topicality of the CBS show "Numb3rs" at the moment, as one of the two stars, Charlie Eppes, played by David Krumholtz, has published a book on friendship maths, using Game Theory.
Andrea Fry

I enjoyed the article but find the prospect of such dating all rather we are just cogs in a machine and every cog just fits neatly into certain other cogs. Maybe it works for some but I have always thought that computer dating is Gods way of telling you to go out and socialise a bit more!
Lee Brown, Thornhill,UK


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