You’re shopping in Central. You run into his ex-girlfriend. They are sharing a memory and laughing over it fondly. No, you are not going to turn into the Incredible Hulk – not physically. But emotionally, you are already ripping out of your clothes. You touch his arm and say, “We have to go, darling”. As you walk off, you tighten your grip possessively on him.

As Valentine’s Day nears, there can be a desire to keep an even shorter leash on our loved ones than usual, and it may even make us more prone to feelings of jealousy, warranted or not. Research suggests this, in turn, can manifest indirectly into more extravagant attention-getting purchases that aim to placate these (hopefully) short-term insecurities.

Studies have found that incidental feelings of jealousy can affect consumers’ preference for attention-grabbing products and that these motivations can carry over to situations that seem unrelated, or even manifest when the person who caused the feelings is not around to witness the behaviour.

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In essence, bumping into an ex-girlfriend may not translate into an immediate row with the boyfriend, or the proverbial silent treatment, but may manifest as binge eating or a shopping spree for attention-grabbing products – things that you would never otherwise buy and may almost certainly never wear, such as a very loud blouse that shouts “look at me”, or a dress with a neckline so plunging you would not wear it without clutching a cardigan over your bosom.

This is because when we get jealous, we feel that the attention we normally get from someone else is being usurped; this stimulates our motivation to try to regain this attention. This motivation can lead us to choose a product that is consistent with this goal – a product that is likely to capture others’ attention.

These warnings are backed up by studies done with 1,138 participants on how jealousy affects purchasing patterns.

In all five experiments, the participants were separated into groups. One group was placed in a controlled condition where they would write about a typical day. Another group would be placed in an emotion-induced condition where they would write about an event when they felt jealous, envious or powerless. Thus stimulated, the groups of participants would be asked to make a product choice.

The results would show if the stimulated emotion affected their consumer decisions.

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In the first experiment, participants were asked to choose between a product that had a big-brand logo versus one that had a small-brand logo. The results confirmed that those who were induced into a state of jealousy were more likely to choose the product with the more conspicuous big-brand logo.

In another experiment, participants were asked to choose between a gold lamp (attention-grabbing) or a grey lamp (non-attention-grabbing) for either a their office or their bedroom. Results showed that jealousy-induced participants were more likely to select the gold lamp when it was used for display in public areas, but not if it were used in a private setting.

This study lends credence to the theory that the motivation of the jealousy-conditioned group was purely to draw attention to themselves rather than based on their own preference for either lamp.

Other experiments also showed the power of jealousy on consumer behaviour.

In jealousy-versus-envy tests, participants were asked to indicate their preference for a brightly coloured coat or a dull coat. Results showed that feelings of jealousy increased participants’ likelihood of choosing the colourful coat; envy did not have a similar effect.

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In the jealousy-versus-powerlessness tests, when choosing between an article of expensive high-end clothing or cheap low-end clothing, powerlessness-control participants picked the attention-grabbing products only when the products were able to enhance their social status. By contrast, jealousy-control participants picked the attention-grabbing products, regardless or not if it signalled a high social status.

In a final telling test, participants were asked whether they would wear either an ordinary pair of sunglasses or an eye-catching pair to two different events – a costume party and a formal party.

The jealousy group indicated a preference for wearing the ostentatious pair of eyewear to the formal event, even if they knew it would be socially inappropriate. By contrast, the powerless-control group, who were motivated differently - to increase their social status, not attract attention - were resistant to choosing glasses that others might consider socially inappropriate.

These studies show that jealousy can cause participants to act in a way – any way – that would get them the attention they desire, often regardless of the reactions that might elicit, regardless of the social appropriateness and regardless if it would hurt their social status.

They also show that jealousy has an unconscious sway over our consumer behaviour. For consumers therefore, it is perhaps useful to shop by a safe rule of thumb - be careful when you go shopping while nursing a jealous wound – or make sure the shop has a return policy.

For retailers looking to sell an ostentatious product, their marketing strategies could include messages that invoke jealous memories in consumers. However, the effects of jealousy will likely work only for goods that can be used in the public space – for example, an eye-catching handbag that be flaunted publicly. However, such a strategy is unlikely to have a similar effect for products used within a personal space, such as a bedroom lamp or a kitchen appliance.

It is noteworthy that the studies show there is no differentiation between gender where the effects of jealousy is concerned; feelings of jealousy can be harnessed to sway both men and women alike to make conspicuous consumption.

From the scripts of the participants, the jealousy effect is not limited to romantic jealousy, but extends to sibling jealousies and jealousy among colleagues as well. Retailers have a large arsenal of recalled experiences to work with.

In essence, it is buyer beware when shopping – but beware not so much the shops as the green-eyed demon from within who may be reawakened by a clever advertising message and propel you to make a less than-than-ideal product choice when in a less-than-secure state of mind.

Xun (Irene) Huang is an assistant professor of marketing and international business at Nanyang Business School, NTU. Her research on the subject was done in collaboration with Ping Dong of Kellogg School of Management, Northwestern University; and Robert S. Wyer Jr with CUHK Business School, Chinese University of Hong Kong.