In a CEPR discussion paper, Òscar Jordà, Björn Richter, Moritz Schularick, and Alan M. Taylor suggest that higher bank capital ratios help stabilize the financial system ex post but not ex ante, and that illiquidity breeds fragility.
Abstract of their paper:
Higher capital ratios are unlikely to prevent a financial crisis. This is empirically true both for the entire history of advanced economies between 1870 and 2013 and for the post-WW2 period, and holds both within and between countries. We reach this startling conclusion using newly collected data on the liability side of banks’ balance sheets in 17 countries. A solvency indicator, the capital ratio has no value as a crisis predictor; but we find that liquidity indicators such as the loan-to-deposit ratio and the share of non-deposit funding do signal financial fragility, although they add little predictive power relative to that of credit growth on the asset side of the balance sheet. However, higher capital buffers have social benefits in terms of macro-stability: recoveries from financial crisis recessions are much quicker with higher bank capital.
In an NBER working paper, David Weil argues that Thomas Piketty overestimates wealth inequality. In the abstract of the paper, Weil writes:
In Capital in the 21st Century, Thomas Piketty uses the market value of tradeable assets to measure both productive capital and wealth. As a measure of wealth this is problematic because it ignores the value of human capital and transfer wealth, which have grown enormously over the last 300 years. Thus the constancy of the wealth/income ratio as portrayed in his data is an illusion. Further, the types of wealth that he does not measure are more equally distributed than tradeable assets. The approach also incorrectly identifies capital gains due to reduced discount rates as increases in the capital stock.