Scientists trying to make a scientific approach to the constant changes in the fashion industry found that what's hot in baby names, dog breeds, clothing "must haves" and chart-topping music is provoked by random copy-cats.

Therefore, whether skinny-leg or boot-cut jeans become the ultimate fashion, is up to chance.

If you do not appreciate the outcome, it's crystal clear: you're out of fashion.

Fashions come and go at a surprisingly steady rate, fueled by very few innovators and copied by millions of people imitating each other.

This conclusion challenges some classic economic theories concerning decision-making among individuals of a consumer culture. "It doesn't necessarily have to involve any rational decisions to get all the way up to the top," said lead author Alex Bentley of Durham University in England.

Bentley's team analyzed the Billboard Top 200 chart of the most popular songs from the 1950s through the 1980s. The turnover rate was relatively constant, of roughly 6 % monthly over the entire 30 years. The most-popular lists for baby names and dog breeds appeared constantly in turnover within each "market."

The team developed computer simulations based on a system of random copying in a pool of hundreds or thousands of individuals copying each other and just up to 2 % being innovators.

This model delivered consistent turnover rates that fitted the real-world data. The pace at which something comes into and gets out of fashion was linked to the size of the list, with a top-100 list suffering changes quicker than a top-40 list, but the population number did not inflict any effect on turnover rate.

A larger population means more new ideas, but when they surpass a certain number, more competition comes up for a top spot and this balances the situation.

The more trend-setting innovators in a society, the faster the rhythm of trend change. "Innovators are the cool ones who 'pump' new fashions into our world," said Bentley.

This research suggests that the actions of some captains of the fashion industry to impose the next consumer "gems" amongst millions of variants is useless.

Even if unpredictable, the advantage of the fashion world is that "change" is the commodity and if you want to thrive, you must continuously change. "Madonna is a great example of someone who just radically changes her visual image every year and she's had such an incredible lifespan on the charts because change itself is what we're saying is the actual commodity that pop culture is about", said Bentley.

"Random copying results in irrational decisions, which is perfectly fine for clothing and other music, but it would be detrimental if applied to other arenas in life. Listening to popular opinion constantly can be an unproductive strategy for a lot of things. It leads to constant turnover with no rational basis for what you're settling on. You don't want scientists and politicians paying attention to fashion; you want them thinking independently", said Bentley.