In Europe differences among countries in the overall change in happiness since the early 1980s have been due chiefly to the generosity of welfare state programs - increasing happiness going with increasing generosity and declining happiness with declining generosity. This is the principal...

This paper examined the long memory features of GDP per capita data before the global financial crisis, using a sample of 26 African countries. The study employed fractional integration and tested the stability of the differencing parameter across the sample period for each country. The results...

We analyze a model for N different measurements of a persistent latent time series when measurement errors are mean-reverting, which implies a common trend among measurements. We study the consequences of overdifferencing, finding potentially large biases in maximum likelihood estimators of the...