Studies of gender differences in investment behaviour consistently show that, in the long term, female investors consistently outperform their male counterparts. This is not, Coates stresses, an endorsement of one sex over another. "It's not that one group is better than the other," says Coates. "They're different. It's just that by diversifying the biology of the trading floor you would counterbalance the extreme tendencies."

That's the word they used in the article, so that's the word I used in the title.

However...

During the dotcom boom, it always surprised Coates that the women traders seemed to be relatively immune to the euphoria that engulfed most male traders at the time.

Women seemed to know that a storm was coming. When it comes to the financial markets, Coates says, men are more hormonal than women. Male physiology makes men more attuned to high-frequency risk-taking. "Our latest studies suggest that women are not more risk averse than men," says Coates. "They merely prefer to have more time and information before they take risks."

This would seem to entail traders.

Perhaps the author - like so many - use the term "traders" and "investors" as one in the same.

I had the same question, but I just played it safe and used the term they used in the article.