A large literature on persistence finds that many modern outcomes strongly reflect characteristics of the same places in the distant past. These studies typically combine unusually high t statistics with severe spatial autocorrelation in residuals, suggesting that some findings may be artefacts...

Regressions using data with known locations are increasingly used in empirical economics, and several standard error corrections are available to deal with the fact that their residuals tend to be spatially correlated. Unfortunately, different corrections commonly return significance levels that...

Empirical researchers often have to map data provided for a "reporting" spatial unit, say counties in 1900, to a "reference" one, say, counties in 2010. We discuss a general method to create such crosswalks: computing the share of the area of each reporting unit nested in a given reference unit....

Empirical researchers often have to map data provided for a "reporting" spatial unit, say counties in 1900, to a "reference" one, say, counties in 2010. We discuss a general method to create such crosswalks: computing the share of the area of each reporting unit nested in a given reference unit....