Peaks and troughs in the spatial distributions of population, employment and wealth are a universal phenomenon in search of a general theory. Such spatial imbalances have two possible explanations. In the first one, uneven economic development can be seen as the result of the uneven distribution...

We develop a structural framework that allows us to quantify the evolution of aggregate bilateral trade costs and markups over time. With minimal assumptions, we can disentangle aggregate markup and trade cost changes from observed changes in trade flows. We apply our method to trade data...