I recently printed a small mountain of papers for my ongoing research projects about Walmart. One thing this illustrates is just how little we actually know about what we might claim to understand and be able to plan.
In our papers on Walmart, Charles Courtemanche and I have estimated the effects of Walmart expansion (measured several ways) on different indicators. This is useful economic history: we can claim, for example, that Super Walmart expansion accounts for about 10% of the increase in obesity over the last twenty years or so, and it seems reasonable to expect that continued Super Walmart expansion will lead to more obesity. It does not justify intervention, though, because while we can construct crude estimates of the costs of Super Walmart-induced obesity (very small) and the savings from Super Walmart’s effects on prices and incomes (very large), we can’t measure all of the relevant tradeoffs and construct incentives that get things just right while remaining free from political influence.
