In the conduct of empirical macroeconomic research, unit root, cointegration, common cycle, and related test statistics are often constructed using logged data, even though there is often no clear reason, at least from an empirical perspective, why logs should be used rather than levels....

One of the fundamental problems of the positive theory of income taxation is explaining why the statutory income tax schedules in all industrialized democracies are marginal-rate progressive. While it is commonly believed that this is but a simple consequence of the fact that the number of...