Lessons learned from the largest tenure-mix operation in the world : right to buy in the United Kingdom

In the past few decades, urban regeneration policies have taken firm root in many Western European countries. Underlying these regeneration policies is a strong belief in the negative neighborhood effects of living in areas of concentrated poverty, often neighborhoods with a large share of social housing. In Europe, great importance is attached to creating a more diverse housing stock (in terms of tenure and dwelling types) as a means to establishing a more socially mixed neighborhood population. Mixed-housing strategies are embraced explicitly by governments in Finland, France, Germany, the Netherlands, Sweden, and the United Kingdom. The idea is that mixing homeowners with social renters will create a more diverse socioeconomic mix in neighborhoods, removing the potential of negative neighborhood effects. By far the largest tenure-mixing operation in Europe is the Right to Buy (RTB) scheme in the United Kingdom. Since the 1970s, more than 2.7 million socially rented houses have sold at large discounts, mainly to sitting tenants. In this article, we synthesize the outcomes of RTB with regard to neighborhood effects: residualization, neighborhood stability, tenure and social mix, social interactions, and dwelling maintenance. Although we acknowledge substantial socioeconomic benefits of RTB for many individual residents, we find that the neighborhood outcomes of RTB are by no means solely beneficial.Publisher PDFPeer reviewe

On the impact of dispersal asymmetry on metapopulation persistence

Metapopulation theory for a long time has assumed dispersal to be symmetric, i.e. patches are connected through migrants dispersing bi-directionally without a preferred direction. However, for natural populations symmetry is often broken, e.g. for species in the marine environment dispersing through the transport of pelagic larvae with ocean currents. The few recent studies of asymmetric dispersal concluded, that asymmetry has a distinct negative impact on the persistence of metapopulations. Detailed analysis however revealed, that these previous studies might have been unable to properly disentangle the effect of symmetry from other potentially confounding properties of dispersal patterns. We resolve this issue by systematically investigating the symmetry of dispersal patterns and its impact on metapopulation persistence. Our main analysis based on a metapopulation model equivalent to previous studies but now applied on regular dispersal patterns aims to isolate the effect of dispersal symmetry on metapopulation persistence. Our results suggest, that asymmetry in itself does not imply negative effects on metapopulation persistence. For this reason we recommend to investigate it in connection with other properties of dispersal instead of in isolation.Comment: 19 pages, 5 figure

Estimation of drift and diffusion functions from time series data: A maximum likelihood framework

Complex systems are characterized by a huge number of degrees of freedom often interacting in a non-linear manner. In many cases macroscopic states, however, can be characterized by a small number of order parameters that obey stochastic dynamics in time. Recently techniques for the estimation of the corresponding stochastic differential equations from measured data have been introduced. This contribution develops a framework for the estimation of the functions and their respective (Bayesian posterior) confidence regions based on likelihood estimators. In succession approximations are introduced that significantly improve the efficiency of the estimation procedure. While being consistent with standard approaches to the problem this contribution solves important problems concerning the applicability and the accuracy of estimated parameters.Comment: 18 pages, 2 figure