The effect of variability and carryover on average bioequivalence assessment: a simulation study

The purpose of this study was to evaluate the effect of residual variability and carryover on average bioequivalence (ABE) studies performed under a 22 crossover design. ABE is usually assessed by means of the confidence interval inclusion principle. Here, the interval under consideration was the standard 'shortest' interval, which is the mainstream approach in practice. The evaluation was performed by means of a simulation study under different combinations of carryover and residual variability besides of formulation effect and sample size. The evaluation was made in terms of percentage of ABE declaration, coverage and interval precision. As is well known, high levels of variability distort the ABE procedures, particularly its type II error control (i.e. high variabilities make difficult to declare bioequivalence when it holds). The effect of carryover is modulated by variability and is especially disturbing for the type I error control. In the presence of carryover, the risk of erroneously declaring bioequivalence may become high, especially for low variabilities and large sample sizes. We end up with some hints concerning the controversy about pretesting for carryover before performing ABE analysis.     

Early Achievement Gains and Poverty-Linked Social Distress: The Case of Post-Head Start Transition

Public policymakers in West Virginia have an intense interest in early and continuing educational intervention for the poor. In this view, interventions such as Head Start are a good idea, but they start too late and end too soon. Properly executed, early and continuing intervention is expected to provide a basis for later achievement-driven improvements in occupational and income attainments. Rural poverty and its correlates, which manifest and cause social distress in a variety of forms, is then diminished. We report on an evaluation of the West Virginia site of a federally-funded program intended to maintain early achievement gains viewed as crucial in alleviating poverty-linked social distress. Results of the evaluation of Post-Head Start Transition show no achievement gains. This undercuts the rationale for the program. Furthermore, it provides no support for a general policy of early and continuing educational intervention to foster achievement-driven diminution of poverty. It seems reasonable to consider the possibility that achievement rises and falls in response to the prevalence and intensity of social distress. Context determines educational outcomes, not the other way around. Reasons are suggested for this.     

On Terrel's characterization of uniform distribution

Terrel (1983) (The Annals of Probability, Vol. 11, No. 3, 823–826) showed that the coefficient of correlation between the smaller and larger of a sample of size two is at most one-half, and this upper bound is attained only for continuous uniform distributions. His proof is of computational nature and is based on the properties of Legendre polynomials. We give an easier proof of Terrel's characterization and we show how our method can be used for obtaining sharper bounds within the class of discrete distributions onN points and also a characterization of the equidistant uniform distribution.     

Restarting “Normal” Life after Covid-19 and the Lockdown: Evidence from Spain,the United Kingdom,and Italy

Social Indicators Research - In this article, we examine the expectations of the economic outlook, fear of the future, and behavioural change during the first Covid-19 wave, for three European...     

Obstacles invisibles et représentation des femmes aux postes de décision en Espagne

Les auteurs présentent les résultats d'une étude sur les caractéristiques personnelles et les qualifications d'hommes et de femmes assumant des fonctions de direction dans des entreprises espagnoles, leur situation professionnelle et leur point de vue sur l'égalité des sexes. Par rapport à leurs homologues masculins, les Espagnoles occupant des postes à responsabilités sont plus jeunes mais aussi qualifiées, voire plus, et elles ont moins d'enfants. Cependant, elles sont toujours confrontées à des obstacles qui empěchent la pleine exploitation d'un capital humain précieux. Malgré les mesures adoptées, plus de neuf postes de décision sur dix sont toujours occupés par des hommes.     

Interview With Michael Kerr

The following article was written by Dr Michael Kerr in response to questions put to him by Barbara Fraser; Linda Mackay and Lu Pease when he visited Australia two years ago. These three family therapists took it upon themselves to prepare this interview in recognition of Dr Kerr's unique vantage point on Bowen Theory and family therapy. Michael Kerr was trained by Murray Bowen in the 1970s and subsequently went on to work as faculty at the Georgetown Family centre. He succeeded Bowen as director of the centre where he has devoted his professional life to the understanding, application and extension of theory. He is the co‐author with Dr Bowen of Family Evaluation: An Approach Based on Bowen Theory (Kerr & Bowen, 1988), which remains the most esteemed text on this theory. He is also the editor of Family Systems: A Journal of Natural Systems Thinking in Psychiatry and The Sciences. Bowen's Family Systems Theory grew out of years of research from the 1950s‐1970s, which included observations of inpatient families with a schizophrenic member and using data from Bowen's own interactions with his family of origin (Bowen, 1978). The theory continues to be influential in family therapy with its most well‐known contributions being the process of triangling, the intergenerational transmission of family patterns and the concept of differentiation of self. (Brown, 1999). The following discussion from Dr Kerr brings a fresh perspective on the current applications and developments of this systems theory     

Participation of seniors in the Argentinian labour market: An option value model*

The aim of this article is to define the factors which determine seniors' decisions to continue to participate in the labour market in Argentina. An option value model is developed. This model is used to produce estimates based on micro‐data drawn from household surveys. These indicate the relative importance of the impact of conditions governing eligibility for benefits on decisions to remain actively employed. Work history is found to be the main factor in such decisions. Inadequacy of social security benefits and accumulated human capital also create incentives for economic participation in old age. On the basis of these findings, compensatory policy adjustments, to improve coverage, increase benefit levels and improve employment conditions for seniors, are proposed.     

ANOVA-like analysis of matched series of studies with a common structure

It is shown how to condense the information contained in a series of studies, each constituted by an objects by variables matrix and a pair of weight matrices, into a structure vector and a sum of sums of squares of residuals. Based on this condensation we propose to carry out ANOVA-like inference for matched series of studies associated with the level combinations of some factors. It is shown how to validate the assumptions underlying the inference. An application to the results of local elections in Portugal is given.     

Clinic Overbooking to Improve Patient Access and Increase Provider Productivity*

The problem of patient no‐shows (patients who do not arrive for scheduled appointments) is significant in many health care settings, where no‐show rates can vary widely. No‐shows reduce provider productivity and clinic efficiency, increase health care costs, and limit the ability of a clinic to serve its client population by reducing its effective capacity. In this article, we examine the problem of no‐shows and propose appointment overbooking as one means of reducing the negative impact of no‐shows. We find that patient access and provider productivity are significantly improved with overbooking, but that overbooking causes increases in both patient wait times and provider overtime. We develop a new clinic utility function to capture the trade‐offs between these benefits and costs, and we show that the relative values that a clinic assigns to serving additional patients, minimizing patient waiting times, and minimizing clinic overtime will determine whether overbooking is warranted. From the results of a series of simulation experiments, we determine that overbooking provides greater utility when clinics serve larger numbers of patients, no‐show rates are higher, and service variability is lower. Even with highly variable service times, many clinics will achieve positive net results with overbooking. Our analysis provides valuable guidance to clinic administrators about the use of appointment overbooking to improve patient access, provider productivity, and overall clinic performance.