Predictability of designs which adjust for imbalances in prognostic factors

Minimisation is a method often used in clinical trials to balance the treatment groups with respect to some prognostic factors. In the case of two treatments, the predictability of this method is calculated for different numbers of factors, different numbers of levels of each factor and for different proportions of the population at each level. It is shown that if we know nothing about the previous patients except the last treatment allocation, the next treatment can be correctly guessed more than 60% of the time if no biased coin is used. If the two previous assignments are known to have been the same, the next treatment can be guessed correctly around 80% of the time. Therefore, it is suggested that a biased coin should always be used with minimisation. Different choices of biased coin are investigated in terms of the reduction in predictability and the increase in imbalance that they produce. An alternative design to minimisation which makes use of optimum design theory is also investigated, by means of simulation, and does not appear to have any clear advantages over minimisation with a biased coin.     

Action-research and the Production of Knowledge in a Teacher Education based on Inter/Multicultural Education

This paper proposes that the teacher, on the basis of action-research methodology, can produce two types of scientific knowledge: one based on the teacher as researcher (the teacher as ethnographer), and another based on the development of pedagogic action (the teacher as educator). The education of such a teacher, simultaneously a researcher and an educator, is carried out through the concretisation of that which has denominated the interface of intercultural education. The development of this interface renders possible the management of diversity by the teacher. This diversity is present both in the school, as well as, more specifically, in the classroom. It can also be seen as a source of wealth for the further deepening of the democratic nature of both the school and the education system.     

The Career‐O‐Gram: A Postmodern Career Intervention

The authors examine the usefulness of postmodernism in career counseling. Specifically, a case is made for broadening career counseling theories and techniques to feature the contextual influences inherent in each individual's unique career history. A career intervention, titled the Career‐O‐Gram, is introduced as a tool for exploring contextual influences on career development. A case study is presented to demonstrate the application of the Career‐O‐Gram.     

Generational Differences in Attitudes and Socioeconomic Status among Hispanics in Houston

The complex variety of experiences that characterize the current wave of immigration have prompted revisions in the classic model of straight-line assimilation; the most important alternative theory is based on the concept of "segmented" assimilation. This paper assesses the validity of these two perspectives with data on three generations of Hispanic immigrants in Houston. Contrary to the standard assimilation model, third-generation Hispanics are not staying in school longer, nor are they earning higher wages than members of the second generation. But contrary to the segmented-assimilation model, third-generation Hispanics also give no evidence at all of having assimilated into an "adversarial" culture that rejects mainstream American values and is presumably responsible for restricting their upward mobility. The data reaffirm the pivotal role of education in determining occupational mobility, and they point to the importance of identifying the external societal factors that account for the stalled progress in educational achievement among third-generation Hispanic Americans.