Power Relations and Social Mix in Metropolitan Neighbourhoods in North America and Europe: Moving Beyond Gentrification?

Research on spatial segregation has suggested that social mix may be a temporary phase in class displacement, where relations between different groups are at best divided or ‘tectonic’, for instance in England. Political and policy discourses, by contrast, tend to uncritically valorize social mix as a means to breaking up concentrations of poverty and providing neighbourhoods with a middle‐class voice. In the literature, little attention has been paid to power dynamics in socially mixed neighbourhoods and the implications this may have for understanding theory and policy. The five articles that make up this symposium address the ways in which social and ethnic groups interact in major cities in Europe and North America and, as the title suggests, this involves taking into account power relations, domination and negotiation between the different groups. There is a need to connect the experience of the deployment of power within neighbourhoods (and between them) with the discussions of power mechanisms at work in wider urban processes.     

THE LIBERAL DEMOCRATS AND SUPPLY‐SIDE ECONOMICS

The coalition has given the Liberal Democrats the opportunity to demonstrate their support for – or opposition to – supply‐side economics. The person who has done most on the supply side is Ed Davey, in the Department of Business, Innovation and Skills. In a remarkable legislative achievement for a Parliamentary Under Secretary in under two years in office, Davey ensured that the privatisation of Royal Mail reached the statute books, liberalised the terms and conditions for Post Office counters, and liberalised employment and retirement laws.     

Jumps and betas: A new framework for disentangling and estimating systematic risks

We provide a new theoretical framework for disentangling and estimating the sensitivity towards systematic diffusive and jump risks in the context of factor models. Our estimates of the sensitivities towards systematic risks, or betas, are based on the notion of increasingly finer sampled returns over fixed time intervals. We show consistency and derive the asymptotic distributions of our estimators. In an empirical application of the new procedures involving high-frequency data for forty individual stocks, we find that the estimated monthly diffusive and jump betas with respect to an aggregate market portfolio differ substantially for some of the stocks in the sample.     

Continuous‐time models,realized volatilities,and testable distributional implications for daily stock returns

We provide an empirical framework for assessing the distributional properties of daily speculative returns within the context of the continuous‐time jump diffusion models traditionally used in asset pricing finance. Our approach builds directly on recently developed realized variation measures and non‐parametric jump detection statistics constructed from high‐frequency intra‐day data. A sequence of simple‐to‐implement moment‐based tests involving various transformations of the daily returns speak directly to the importance of different distributional features, and may serve as useful diagnostic tools in the specification of empirically more realistic continuous‐time asset pricing models. On applying the tests to the 30 individual stocks in the Dow Jones Industrial Average index, we find that it is important to allow for both time‐varying diffusive volatility, jumps, and leverage effects to satisfactorily describe the daily stock price dynamics. Copyright © 2009 John Wiley & Sons, Ltd.     

Under-connected and over-connected networks: the role of externalities in strategic network formation

Since the seminal contribution of Jackson and Wolinsky (J Econ Theory 71(1):44–74, 1996) it has been widely acknowledged that the formation of social networks exhibits a general conflict between individual strategic behavior and collective outcome. What has not been studied systematically are the sources of inefficiency. We approach this omission by analyzing the role of positive and negative externalities of link formation. This yields general results that relate situations of positive externalities with stable networks that cannot be “too dense” in a well-defined sense, while situations with negative externalities tend to induce “too dense” networks. Those results are neither restricted to specific assumptions on the agents’ preferences (e.g. homogeneity), nor to a specific notion of stability or efficiency.     

Milk sales and dietary diversity among the Maasai

In Maasai culture, responsibilities are traditionally divided between genders. Men are in charge of grazing and managing the livestock herds. Women take care of the family, administer food supplies, and are responsible for milking. For them, balancing home consumption of milk (for the family and for the calves), milk sale, and food purchase is a major task. In this article, we first investigate how different milk sales groups vary regarding the use of different food items and the respective quantities consumed by the enkaji, i.e., a Maasai subhousehold. Then, we address the commercialization decision and assess the effect of milk sales on the enkaji's food item use and food consumption. Using the data of Maasai enkajijik in the milk catchment area of a milk collection center in Ngerengere, Tanzania, we estimate the effects by employing propensity score matching procedures. Our findings suggest that milk sellers, especially those selling to the milk collection center, have a more diverse diet. In terms of per person consumption, the groups are markedly similar. Therefore, we conclude that income generated by milk sales is invested in diet diversification rather than in increasing the quantity of food consumed, hence the enkajijik appear not to make use of caloric terms of trade.