An important question in the field of political economy is whether a country's economic development fosters political democracy. For example, using statistical analyses of nations, scholars have concluded that development increases democracy by producing a middle class and tolerant attitudes, or by increasing the division of labor which creates a demand for more complex political institutions. In contrast, comparative historical research finds that the effect of economic development on political democracy is contingent, varying greatly across countries and historical periods. Thus, research in this area yields depending on method used (comparative-historical or statistical) divergent findings. Kim and Kim will seek to reconcile this devergence using improved measures models for time series data.