Do states optimize? Public capital and economic growth

This paper develops a non-linear theoretical relationship between public capital and economic growth in order to obtain estimates of the growth-maximizing ratio of public capital to private capital. The model is empirically implemented using data on the 48 contiguous U.S. states over the period 1970 to 1990. The empirical results provide evidence that (i) the relationship between public capital and economic growth is non-linear, (ii) the growth-maximizing public capital stook is approximately 60%;, to 80% as large as the private (tangible) capital stock, and (iii) permanent changes in public capital are associated with permanent changes in economic growth.