Examines the origins and reasons for the predominance of royal rule in medieval Europe and traces the rise and decline of feudalism

This report examines the relationship within urban housing markets between residential mobility and housing opportunity. The basic unit of analysis is neither households nor housing units but rather vacant housing opportunities. Objectives are threefold. The first is to clarify concepts about opportunity and mobility within housing markets. Clarification begins with the observation that mobility is limited to a set of currently vacant housing opportunities, continues through reasons for the existence of opportunity differentials and proceeds toward the development of historically and structurally based theories of intraurban residential mobility. The second objective is to define the mathematical structure of a pair of multisectoral residential vacancy chain models that operationalize these concepts. These models simulate the transfer of vacant housing opportunities among housing sectors in response to either the creation of new opportunites or the absorption of existing ones. Residential mobility is given as an analytical by-product. The third objective is to calibrate these models and gauge the accuracy of their projections. Vacancy transfer models are shown to be useful in housing programme assessment, in the assessment of regional housing needs and in the design of local housing programmes. Their core matrices are useful in tracing chains of opportunities among housing sectors, in determining whether opportunities filter down to those who cannot afford newly constructed units and in defining the ways in which in-migrants and newly formed household support residential mobility among existing residents.