Urban rent and urban dynamics: The determinants of urban development in Italy

Many empirical analyses have proved the existence of an optimal city size through the measurement of economies or diseconomies of scale, generally applied either to the costs of urban services or to elegant econometric estimates of urban and sectoral production functions. But, unfortunately these studies have never produced a common result, and have often been subject to criticism for their restrictive hypotheses. The aim of the present paper is twofold. First of all, urban dynamics in Italy is described through an indicator of urban costs and advantages, i.e. urban rent. House prices are in fact a good indicator of the attraction of an urban area, as they are synthetic and avoid a time lag between the occurrence of phenomena such as demographic change, and the availability of data to capture these phenomena. This study is based on the idea that the difference in house prices between large and small cities is a measure of their relative attraction (and thus their relative location advantage). The second aim is to highlight the determinants of urban dynamics, and especially to understand whether urban development patterns are similar in cities of different size. For this second issue, the paper enters the debate on the existence of an optimal city size for all cities and draws attention to other possible determinanats of urban development.