The Albrecht and Axell model is not the only framework that can generate equilibrium wage dispersion, but that is not the issue in my view. The endemic problem in estimating such models is the extreme paucity of data. The Eckstein and W olpin effort is a demonstration of structure substituting for data in an extreme form. It will be impossible to compare alternative equilibrium formulations with any statistical power if the only data that is available is that on workers. As with the partial equilibrium search model, a much more intensive data collection effort is required.55