Something comes over us when we go shopping

They call it 'consumer behaviour'' at business schools, but we call it shopping.

So should we have professors of shopping to help us understand the psychological processes involved? Could there be a science of shopping to help shops maximise their profit?

Certainly many myths surround the topic. Take conspiracy theories about supermarket layout. First, the two staples bread and milk are furthest apart to keep you walking the aisles and impulse buying. No, they are in different places mainly for temperature reasons. Second, supermarketeers deliberately try to disorientate you by moving stuff around. Not true. Relocating goods really annoys punters and sales drop if shops do it regularly. Changes are made for new stock or to eliminate poorly selling ranges.

There are three methods of collecting shopping science data. To start, stock, cash and sales - that's quite simple and reliable. Loyalty cards too provide good data on time and purchase details. Or if we think they will tell us the truth, we can interview people.

Retailers are interested in particular questions: the conversion rate (the number of people entering stores who actually purchase anything); the interception rate (the number of customers who interact with staff members); how long people actually spend in a store; and how long they have to wait for service, especially paying.

Time spent in a store is the best predictor of how much is spent, so slowing people down is a good thing. But it is not a good idea to slow them down with poor signage and blocked aisles.

Signage is very important. People like to sit down in shops. Music and smells can affect moods and thence purchases. People need ways of easily carrying things and they tend to have habitual ways of moving around the store.

But what about individual differences? There are, of course, shopper types: adventure shoppers; shopaholics and shopaphobics; economic shoppers and price-insensitive Johnnies; bargain hunters and sociable shoppers.

Women spend more time shopping than men. They seem to be more aware, inquisitive and patient in shops. Men, it seems, move faster, look less and are less inclined to ask questions. Men seem more anxious to get out of the store. Men inhibit women shoppers. Women accompanied by men spend half the time than if accompanied by other women.

Women advise, consult and talk. Men get on with it. Women find shopping relaxing but men are hunter-gatherers. They need a list and to know what brand, colour, size and style. Men go for a quick kill.

Then there are the pathologies associated with shopping addictions and compulsions, including shoplifting, from which a disproportionate number of women seem to suffer. There is, too, the concept of retail therapy: the shopper is really a profoundly unhappy person trying to "buy relief'' in big stores. So it seems we may need professors of shopping science to explain to us why we act so oddly in shops.

Adrian Furnham is professor of psychology at University College London

Adrian Furnham, 'The Daily Telegraph', 15 December 2005