The story starts off with this:

Women given testosterone for a month were no more likely than women not receiving the hormone to engage in risky financial decisions, according to researchers in Sweden. The findings could suggest that women are a safer pair of hands on the stock-market trading floor than men – or throw into doubt earlier findings about the effect of the hormone on men.

A spate of recent studies have found correlations between testosterone levels and risky behaviour in men, including one that found that male securities traders with more testosterone in their saliva made riskier financial decisions.

But now a team led by Magnus Johannesson, an economist at the Stockholm School of Economics, has found no such effects in a group of 200 post-menopausal women. The women were administered testosterone, oestrogen or a placebo for four weeks and asked to play a series of economic games that measure the player's propensity to take risks, their trust and their willingness to share resources.

One researcher notes:

"I'm relatively pessimistic of finding an effect in men," Johannesson says. He writes in the paper that it is possible that previously published links between testosterone and risk-taking are "spurious". Studies that do not find a correlation between sex hormone levels and economic behaviour may simply have a harder time getting published. "Negative correlation results don't get published," he says.

The original research is here.  I would simply urge caution in interpreting results from this area.  We're not yet in a "safe zone" of knowing what replicable results look like.

Groups talk about what they already know:

A new meta-analysis (pdf) of 72 studies, involving 4,795 groups and over 17,000 individuals has shown that groups tend to spend most of their time discussing the information shared by members,
which is therefore redundant, rather than discussing information known
only to one or a minority of members. This is important because those
groups that do share unique information tend to make better decisions.

Another important factor is how much group members talk to each other. Ironically, Jessica Mesmer-Magnus and Leslie DeChurch found that groups that talked more tended to share less unique information.

Hey, Alex, demand curves slope downwards!  Hey Robin, people signal!  Hey, Bryan, etc.

Gretchen Rubin interviews Todd Kashdan (of GMU I might add, though I don't know him):

Is there anything you find yourself doing repeatedly that gets in the way of your happiness?
There is a dark side to my desire to become an expert in psychology,
knowledgeable about science and literature, skilled as a parent,
mountain biker, and weightlifter, and attentive as a husband. When I
think I know something, I stop paying attention. It happens far too
often and when it does, opportunities close. I constantly have to
remind myself to let go of my ego, let go of my expectations, and stay
flexible and profoundly aware of what is right in front of my senses.

Here is Todd's new blog.  Here is Todd on the Mayan afterlife.  Here is Gretchen's version of phony advertising markets in everything.

Here is Todd's home page, with Todd's lists.