Back in the time before Facebook, YouTube and even Tinder – yes, it’s hard to believe there really was such a time – two young male engineers at Berkeley got into a disagreement over the attractiveness of a passing woman.

What we see as beautiful is dynamic – in other words, constantly changing – and is highly influenced by the views of others

The disagreement spurred them to develop a website,, which hit the web in late 2000 and quickly became one of the internet’s hottest properties. For a few years HOTorNOT drew millions of visitors, young and old, who burned through hours of time busily rating the hotness or otherwise of anyone who cared to upload their photo.

It might seem unremarkable now, but back in the early 2000s the idea was groundbreaking.

HOTorNOT pioneered the now widespread concept of rating things and became a trailblazer in the now pervasive world of social media. It even influenced the earliest incarnation of what started out as The Facebook (the pronoun did not last long).

New insights

As a professor of marketing, the emergence of HOTorNOT and its many imitators and successors has opened up exciting new insights into understanding the processes of human attraction and the factors at play when Cupid’s arrow strikes.

I’m interested in how consumers evaluate marketing communications such as advertisements, and how this shapes their choice of products and brands. So understanding how we judge attractiveness and the factors influencing this process are keys to explaining what draws people to certain things above others.

hotornotFor centuries we have been told that “beauty is in the eye of the beholder”. It’s a saying supported by several studies which suggest that eons of natural selection has hardwired our perceptions of what is physically attractive, all driven by the ultimate goal of finding healthy mates and perpetuating our genes.

Another factor long assumed to influence aesthetic taste are changes in socioeconomic or cultural norms, for example whether a fuller or slimmer figure is considered more attractive. Such norms generally change only very slowly, over decades or even centuries.

But in recent research using data gathered from a dating website similar to that pioneered by HOTorNOT a rather different picture has emerged; one that challenges the notion that what we see as beautiful or attractive is so rigid or inbuilt.

Dynamic beauty

In a series of studies and experiments conducted by myself at NUS Business School and Haiyang Yang at the Carey Business School at Johns Hopkins University in the US, we found that what we see as beautiful is dynamic – in other words, constantly changing – and is highly influenced by the views of others.

In fact, we found that individuals often automatically modify their standards of assessing beauty when they are exposed to the views of others, and do so virtually instantaneously.

absWhat’s hot and what’s not can be shaped by the views of othersIn our first study we used data gathered anonymously from the activities of more than 60,000 visitors to a dating website, giving us a data-set of around 800,000 separate ratings in which users evaluated a random series of photos on a scale from 10 (hot) to one (not).

Following the standard practice of rating websites, after each individual had posted his or her rating, the site then displays the combined average score given by every user who had previously rated the photo in question.

This, we noticed, triggered an interesting effect. Over time, as individual users rated more photos, their ratings of who was “hot” and who was “not” would shift – becoming closer and closer to the average. This shift occurred even though each users’ attractiveness ratings were posted anonymously, without anyone else observing, and hence free of the effects of any direct social pressure to conform to the norm.

Lab experiments

Given this pattern in the data, we took the study into a lab-based experiment, and tweaked some of the conditions.

For some users the average rating for a photo was posted before they posted their own rating; for others the average was revealed afterwards; and in a third case no average was revealed at all.

In both of the first two cases, as more and more images were shown and rated, users would steadily shift the assessment closer to the average rating. However, those who saw no average score did not shift their perceptions to align with the broader consensus.

ThinkAloud4We then added a fourth variable to the experiment, showing users an average group rating after they had rated each photo, but in some cases creating a fake average, lower than the actual average of previous scores. In this case, users shown the fake low averages began over time to post ratings further from the true average.

Furthermore, most participants interviewed after the study said that seeing the average scores of the group had not played any role in affecting their judgement.

These results raise the notion that our perceptions of what is attractive – or “hot” – is not only highly dynamic and subject to being shaped by the views of others, but could also be artificially manipulated.

Our study casts a new light on how perceptions of physical attractiveness are formed with implications for business and many other fields.

Rather than being inbuilt as a result of natural selection, or shaped by gradual changes in cultural or societal trends, it shows that our judgements on aesthetics and attractiveness can be formed instantaneously and can be altered by exposure to the judgements and views of others. In other words when Cupid draws back his bow, the target may be constantly changing – right up until the arrow starts to fly.

Beauty may indeed be in the eye of the beholder, but what our eyes see as “hot” is by no means set in stone.