Robert W. Helsley

Learn More
It is well established that the thickness of local markets can enhance entrepreneurial activity (Vernon (1960)). It has been more recently established that because they carry out so many different tasks, a balance of skills may be beneficial to entrepreneurs (Lazear (2004, 2005)). This paper unifies these approaches to agglomeration and entrepreneurship.(More)
Since Marshall (1890), it has been common for economists to model knowledge transfers as exogenous spillovers. However, there are many instances of knowledge transfers that are deliberate and reciprocal. This paper models these endogenous knowledge transfers and shows that endogenous knowledge barter is fundamentally different than exogenous spillovers.(More)
We examine how interaction choices depend on the interplay of social and physical distance, and show that agents who are more central in the social network, or are located closer to the geographic center of interaction, choose higher levels of interactions in equilibrium. As a result, the level of interactivity in the economy as a whole will rise with the(More)
The objective of this paper is to show how the same market failures that contribute to urban sprawl also contribute to urban blight. The paper develops a simple dynamic model in which new suburban and older central-city properties compete for mobile residents. The level of housing services generated by older properties depends on current maintenance or(More)
Cities are neither completely specialized nor completely diverse. However, the theoretical agglomeration literature has focused almost entirely on the polar cases of complete diversity and specialization. In order to give theoretical foundations to cluster analysis, this paper develops a model that can also generate the intermediate case of cities that(More)
Traditional models of systems of cities focus almost entirely on the polar cases of completely diverse and completely specialized cities. The former are shown to be the product of urbanization economies, and the latter of localization economies. This paper specifies models that can also generate the intermediate case of cities that feature the(More)
We present a theory of spatial development. Manufacturing and services firms located in a continuous geographic area choose each period how much to innovate. Firms trade subject to transport costs and technology diffuses spatially. We apply the model to study the evolution of the U.S. economy in the last half-century and find that it can generate the(More)
Housing supply plays an important role in the Volatility of macroeconomic cycles and the speed with wl-iich house prices respond to changes in demand, yet it is understudied in the current literature. In this paper we present and estimate a new model of the supply of residential construction that is consistent with the theoretical treatment of land(More)