There’ve been a lot of studies that indicate that women make better investors than men. They’re less inclined to overtrade, which reduces the fees they pay and means they start with an inbuilt advantage. However, there’s not been much analysis of why this behaviour occurs.
For it’s not self-evident that the lack of a pair of testicles should automatically make you a better investor. The pop-psychological view that this is due to surges of testosterone driving risk taking actions by red-blooded alpha males is highly seductive, but also pretty useless. Humans are uniquely evolved to allow us to override the urgings of of our genes, regardless of what sex organs they endow us with.
Cool Female Heads
However, there’s not much doubt that the basic finding – that women are less active traders and produce better returns on average over the long-term – is correct. Odean and Barber showed this in their 2001 study on overconfidence for instance. What’s more interesting, though, is how easily the idea that this is simply due to non-eradicable sex differences is accepted. In fact some observers have gone so far as to suggest that market extremes could be avoided by ensuring more women are present in investment houses – the idea being, presumably, that the cooler headed females will reduce the hot-headed male impulses to trade irrationally.
Like hell. More likely, of course, the presence of additional women would simply stimulate the men into ever more risky trades in feverish attempts to impress them: taking risks may have benefits that don’t translate into pure financial advantage. Meanwhile any women interested enough to get involved in market trading are more likely to do so in order to become rich rather than to act as a self-regulating safety valve for their male colleagues.
Risky Sociobiology
Now before we can investigate this more we need to take a careful look at what causes sex differences. It’s perfectly obvious that our genes have fitted males and females differently for the purposes of reproduction but beyond that it’s surprisingly difficult to definitively tease apart the influences of genes and environment. Even the well known male map reading advantage can be traced to the greater willingness of parents to allow young