Translation: The recent worldwide economic meltdown was caused in part by quants' inability to accurately assess investment risks, or to influence decision-making, or both.
Part of the problem is the science has a feedback effect; theories based on observations change actors' behaviours, which in turn breaks the theories. So macroeconomics is not on very solid ground as a science. It would work better if it were performed by aliens.
The bottom line is that reliable quantitative analysis hinges on the degree to which economics is a science. Economics isn't a science.
I think you're confusing macroeconomics with economics.
Part of the problem is the science has a feedback effect; theories based on observations change actors' behaviours, which in turn breaks the theories. So macroeconomics is not on very solid ground as a science. It would work better if it were performed by aliens.
The bottom line is that reliable quantitative analysis hinges on the degree to which economics is a science. Economics isn't a science.
I think you're confusing macroeconomics with economics.