Galtonian Regression Across Countries and the Convergence of Productivity†

ABSTRACTS A Galton model, in logarithmic form is used to explain the convergence of countries' productivities over time, including β and σ convergence. The ‘regression fallacy’ does not arise. When comparing growths and levels of productivity, countries should be classified by their initial levels of productivity, preferably after logarithmic transformation. Errors in the data may justify using an error‐in‐variables model, or the geometric mean of the original and reverse regressions, but this is not certain.