Testing for non-stationarity and cointegration allowing for the possibility of a structural break: an application to EuroSterling interest rates

In this paper we examine the order of integration of EuroSterling interest rates by employing techniques that can allow for a structural break under the null and/or alternative hypothesis of the unit-root tests. In light of these results, we investigate the cointegrating relationship implied by the single, linear expectations hypothesis of the term structure of interest rates employing two techniques, one of which allows for the possibility of a break in the mean of the cointegrating relationship. The aim of the paper is to investigate whether or not the interest rate series can be viewed as I(1) processes and furthermore, to consider whether there has been a structural break in the series. We also determine whether, if we allow for a break in the cointegration analysis, the results are consistent with those obtained when a break is not allowed for. The main results reported in this paper support the conjecture that the ‘short’ Euro-currency rates are characterised as I(1) series that exhibit a structural break on or near Black Wednesday, 16 September 1992, whereas the ‘long’ rates are I(1) series that do not support the presence of a structural break. The evidence from the cointegration analysis suggests that tests of the expectations hypothesis based on data sets that include the ERM crisis period, or a period that includes a structural break, might be problematic if the structural break is not explicitly taken into account in the testing framework.

International investment, ownership and risk in the City of London office market: an analysis of trends 1972-1997

Office returns in the City of London are more volatile than in other UK markets. This volatility may reflect fluctuations in capital flows associated with changing patterns of ownership and the growing linkage between real estate and financial markets in the City. Using current and historical data, patterns of ownership in the City are investigated. They reveal that overseas ownership has grown markedly since 1985, that owners are predominantly FIRE sector firms and that there are strong links between ownership and occupation. This raises concerns about future volatility and systemic risk.

Challenges in identifying factors which determine the placement of children in care? An international review

Placing a child in out-of-home care is one of the most important decisions made by professionals in the child care system, with substantial social, psychological, educational, medical and economic consequences. This paper considers the challenges and difficulties of building statistical models of this decision by reviewing the available international evidence. Despite the large number of empirical investigations over a 50 year period, a consensus on the variables associated with this decision is hard to identify. In addition, the individual models have low explanatory and predictive power and should not be relied on to make placement decisions. A number of reasons for this poor performance are offered, and some ways forwards suggested. This paper also aims to facilitate the emergence of a coherent and integrated international literature from the disconnected and fragmented empirical studies. Rather than one placement problem, there are many slightly different problems, and therefore it is expected that a number of related sub-literatures will emerge, each concentrating on a particular definition of the placement problem.

Assessing the spatial and temporal variation in the skill of precipitation forecasts from an NWP model

It is becoming increasingly important to be able to verify the spatial accuracy of precipitation forecasts, especially with the advent of high-resolution numerical weather prediction (NWP) models. In this article, the fractions skill score (FSS) approach has been used to perform a scale-selective evaluation of precipitation forecasts during 2003 from the Met Office mesoscale model (12 km grid length). The investigation shows how skill varies with spatial scale, the scales over which the data assimilation (DA) adds most skill, and how the loss of that skill is dependent on both the spatial scale and the rainfall coverage being examined. Although these results come from a specific model, they demonstrate how this verification approach can provide a quantitative assessment of the spatial behaviour of new finer-resolution models and DA techniques.

Planning autonomous vehicles in the absence of speed lanes using an elastic strip

Planning of autonomous vehicles in the absence of speed lanes is a less-researched problem. However, it is an important step toward extending the possibility of autonomous vehicles to countries where speed lanes are not followed. The advantages of having nonlane-oriented traffic include larger traffic bandwidth and more overtaking, which are features that are highlighted when vehicles vary in terms of speed and size. In the most general case, the road would be filled with a complex grid of static obstacles and vehicles of varying speeds. The optimal travel plan consists of a set of maneuvers that enables a vehicle to avoid obstacles and to overtake vehicles in an optimal manner and, in turn, enable other vehicles to overtake. The desired characteristics of this planning scenario include near completeness and near optimality in real time with an unstructured environment, with vehicles essentially displaying a high degree of cooperation and enabling every possible(safe) overtaking procedure to be completed as soon as possible. Challenges addressed in this paper include a (fast) method for initial path generation using an elastic strip, (re-)defining the notion of completeness specific to the problem, and inducing the notion of cooperation in the elastic strip. Using this approach, vehicular behaviors of overtaking, cooperation, vehicle following,obstacle avoidance, etc., are demonstrated.

The neolithisation of Liguria (NW Italy): an environmental archaeological and palaeoenvironmental perspective

The archaeological evidence compiled for Liguria has enabled the formulation of a comprehensive model of Neolithic social, technological and economic development (∼7800–5700 cal yrs BP). The model indicates that during the Early and Middle Neolithic (∼7800–6300 cal yrs BP; ‘Impressed Ware’ and ‘Square Mouthed’ pottery cultures) human activity mainly focussed on low (coastal) and mid-altitude areas. By the Late Neolithic (∼6300–5700 cal yrs BP; ‘Chassey’ culture) farming practices were taking place over a wider range of altitudes and involved transhumant pastoralism. Complementary environmental archaeological and palaeoecological records from caves, open-air sites, lakes and mires indicate that human activities had a more significant impact on the environment than previously thought. This included clearance, especially Abies, Ulmus, Fraxinus and Tilia, and woodland utilisation and management (e.g. leaf foddering), as well as cereal cultivation and animal husbandry. The influence of Middle Holocene climatic changes, especially from ∼7800 cal yrs BP, on the direction of vegetation changes and socio-economic developments during the Neolithic remain uncertain.

Do laws influence the cost of real estate brokerage services? A state fixed effects approach

A FTC-DOJ study argues that state laws and regulations may inhibit the unbundling of real estate brokerage services in response to new technology. Our data show that 18 states have changed laws in ways that promote unbundling since 2000. We model brokerage costs as measured by number of agents in a state-level annual panel vector autoregressive framework, a novel way of analyzing wasteful competition. Our findings support a positive relationship between brokerage costs and lagged house price and transactions. We find that change in full-service brokers responds negatively (by well over two percentage points per year) to legal changes facilitating unbundling

Spectacular foodscapes: food celebrities and the politics of lifestyle mediation in an age of inequality

This editorial introduces a special issue of Food, Culture & Society and works to add a parallel, substantive take on the phenomenon of the food celebrity and the mediated, everyday cultural politics they create. We start by exploring the concept of the foodscape. Specifically, we argue that food celebrities represent a fundamental component of contemporary foodscapes, how they “perform” and function, and the socio-material means by which they are produced. We then explore the key roles and privileges of food celebrity, arguing that the celebrity chef is not the only high-profile, mediating figure at work on the foodscape. Key food celebrity paradoxes are identified and discussed: food celebrities must work to be authentic and aspirational, accessible yet exclusive, responsibilizing but also empowering. We conclude with a short contextualization of the papers in this special issue, and argue for the rich potential of food celebrity scholarship as a way to better understand food inequalities

Media damage following detergent sclerotherapy appears to be secondary to the induction of inflammation and apoptosis: an immunohistochemical study elucidating previous histological observations

Objective/Background: Traditionally, sclerotherapy has been thought to work by the cytotoxic effect of the sclerosant upon the endothelium alone. However, studies have shown that sclerotherapy is more successful in smaller veins than in larger veins. This could be explained by the penetration of the sclerosant, or its effect, into the media. This study aimed to investigate intimal and medial damage profiles after sclerosant treatment. Methods: Fresh human varicose veins were treated ex vivo with either 1% or 3% sodium tetradecyl sulphate (STS) for 1 or 10 minutes. The effect of the sclerosant on the vein wall was investigated by immunofluorescent labelling of transverse vein sections using markers for endothelium (CD31), smooth muscle (a-actin), apoptosis (p53) and inflammation (intercellular adhesion molecule-1 [ICAM-1]). Polidocanol (POL; 3%) treatment at 10 minutes was similarly investigated. Results: Endothelial cell death was concentration- and time-dependent for STS but incomplete for both sclerosants. Time, but not concentration, significantly affected cell death (p > .001). A 40% and 30% maximum reduction was observed for STS and POL, respectively. Destruction of 20e30% of smooth muscle cells was found up to 250 mm from the lumen after 3% STS treatment for 10 minutes. POL treatment for 10 minutes showed inferior destruction of medial cells. Following STS treatment and 24-hour tissue culture, p53 and ICAM-1 were upregulated to a depth of around 300 mm. This effect was not observed with POL. Conclusion: Inflammatory and apoptotic markers show the same distribution as medial cell death, implying that sclerotherapy with STS works by inducing apoptosis in the vein wall rather than having an effect restricted to the endothelium. Incomplete loss of endothelial cells and penetration of the sclerosant effect up to 250 mm into the media suggest that medial damage is crucial to the success of sclerotherapy and may explain why it is less effective in larger veins.

Efficacy of Microwaves and Chlorhexidine on the Disinfection of Pacifiers and Toothbrushes: An In Vitro Study

Purpose: The purpose of this study was to evaluate, in vitro, the contamination of toothbrushes and pacifiers by Streptococcus mutans, and the efficacy of microwave and chlorhexidine for their disinfection. Methods: Sixty pacifiers and 60 toothbrushes were contaminated with S mutans and then divided into groups according to the disinfection protocol: Group 1-chlorhexidine solution; Group 2-microwave sterilization; and Group 3-sterile tap water. The devices were evaluated microbiologically as to the formation of S mutans colonies/biofilms and were examined by scanning electron microscopy. The results were submitted for statistical analysis by Friedman`s test at a 5% significance level. Results: The results of both types of evaluation showed a large number of S mutans colonies/biofilms after spraying with sterile tap water, and chlorhexidine spraying and microwaving were effective in eliminate colonies/biofilms. Groups 1 and 2 were statistically similar to each other (P>.05) and differed significantly from Group 3 (P<.05). Conclusions: The 0.12% chlorhexidine solution spray and 7 minutes of microwave irradiation were effective for disinfection of pacifiers and toothbrushes. (Pediatr Dent 2011;33:10-3) Received July 29, 2009 I Last Revision January 26, 2010 I Accepted March 10, 2010

On the concept of electrical impedance for an electrolytic cell

The analysis of the electrical impedance of an electrolytic cell in the shape of a slab is performed. We have solved, numerically, the differential equations governing the phenomenon of the redistribution of the ions in the presence of an external electric field, and compared the results with the ones obtained by solving the linear approximation of these equations. The control parameters in our study are the amplitude and the frequency of the applied voltage, assumed a simple harmonic function of the time. We show that for the large amplitudes of the applied voltage, the actual current is no longer harmonic at low frequencies. From this result it follows that the concept of electrical impedance of a cell is a useful quantity only in the case where the linear approximation of the fundamental equations of problem work well.

The number of open paths in an oriented rho-percolation model

We study the asymptotic properties of the number of open paths of length n in an oriented rho-percolation model. We show that this number is e(n alpha(rho)(1+o(1))) as n ->infinity. The exponent alpha is deterministic, it can be expressed in terms of the free energy of a polymer model, and it can be explicitly computed in some range of the parameters. Moreover, in a restricted range of the parameters, we even show that the number of such paths is n(-1/2)We (n alpha(rho))(1+o(1)) for some nondegenerate random variable W. We build on connections with the model of directed polymers in random environment, and we use techniques and results developed in this context.