12 May 2016
Amy Isham is a Psychology of Advertising MSc student at Lancaster, and her undergraduate dissertation won the Experimental Psychology Society and British Science Association national prize for undergraduate research. Here she talks about her findings.

My prize-winning student research has shown that more advertising means less impulse buying online.

For retailers, it's important to know what might make shoppers buy on impulse. So far, we know quite a bit about how this happens in bricks-and-mortar stores.

But now retailers want to know more about impulse buying, and how to influence it online. Research has found that appealing, personalised, and interactive websites lead to more impulse buying. We also know that some people are generally more likely to impulse buy – this is a personal characteristic.

There is an interesting effect called the Distractor Devaluation Effect though, that may mean that companies waste money by trying to advertise goods too many times.  When people see something and have to ignore it, they start liking it less. If they have seen it on an online store, they make be less likely to buy it on impulse now they like it less.

I looked at whether having to ignore ads for products in an online store meant that people would not buy these products impulsively at checkout, and compared this to when people don't see the products before checkout.

This way we can work out whether advertisers are wasting money by placing their products where shoppers see them multiple times in one website visit.

We created a special website consisting of a ‘hoodies and sweaters’ product page and a checkout page. Volunteers were asked to buy a hoody for their friend. For some volunteers, three products (phone case, mug and socks) were advertised at the top of the ‘hoodies and sweaters’ page under the title of “OFFER: Items Below at a Reduced Price for a Limited Time Only”.

‌Others didn't see these three items.. All our volunteers were then given an opportunity to buy one of the three items at checkout.

We also looked at how likely our volunteers were in general to buy impulsively – their personal level of impulsive buying. We wanted to see if having the "impulse buys" visible worked differently for impulsive buyers and not particularly impulsive shoppers.

Shoppers who saw the three impulse buys before checkout were less likely to buy one of the impulse buy items at checkout than shoppers who didn't see the impulse buys beforehand. As we suspected, shoppers who saw the impulse buy items and had to ignore them, seemed to like the impulse buy goods less than shoppers who'd never seen them before. 

This shows us that the Distractor Devaluation effect does apply to online shopping and too much advertising may be a bad thing for companies that want to increase impulse purchases.

Everyone seemed to be affected by seeing the impulse buy items before checkout, though – neither the impulsive nor the non-impulsive shoppers were more or less likely to impulse buy when they'd seen the "offer" items before checkout.

 My recommendation for advertising is that extra ads should be avoided when shoppers are likely to be concentrating on choosing their main purchase; impulse buys work better when they show up for the first time at checkout.