Iterated Partial Sum Sequences of Regression Residuals and Tests for Changepoints with Continuity Constraints

Iterated partial sum sequences of regression least squares residuals are defined and large sample properties of sequences of stochastic processes defined by these iterated partial sums are discussed. Also, finite sample properties of the iterated partial sum sequences are obtained. These include a property of least squares residuals of polynomial fits to equispaced data, namely the iterated partial sums sum to 0 provided that the order of iteration is not greater than the order of the polynomial, thus extending the well-known result that residuals sum to 0. Iterated partial sums are shown to play an important role in testing regression parameters for changes at unknown times under the constraint of continuity.     

The use of sparsest cuts to reveal the hierarchical community structure of social networks

We show that good community structures can be obtained by partitioning a social network in a succession of divisive sparsest cuts. A network flow algorithm based on fundamental principles of graph theory is introduced to identify the sparsest cuts and an underlying hierarchical community structure of the network via maximum concurrent flow. Matula [Matula, David W., 1985. Concurrent flow and concurrent connectivity in graphs. In: Alavi, Y., et al. (Eds.), Graph Theory and its Applications to Algorithms and Computer Science. Wiley, New York, NY, pp. 543–559.] established the maximum concurrent flow problem (MCFP), and papers on divisive vs. agglomerative average-linkage hierarchical clustering [e.g., Matula, David W., 1983. Cluster validity by concurrent chaining. In: Felsenstein, J. (Ed.), Numerical Taxonomy: Proc. of the NATO Adv. Study Inst., vol. 1. Springer-Verlag, New York, pp. 156–166 (Proceedings of NATO ASI Series G); Matula, David W., 1986. Divisive vs. agglomerative average linkage hierarchical clustering. In: Gaul, W., and Schader, M. (Eds.), Classification as a Tool of Research. Elsevier, North-Holland, Amsterdam, pp. 289–301; Thompson, Byron J., 1985. A flow rerouting algorithm for the maximum concurrent flow problem with variable capacities and demands, and its application to cluster analysis. Master Thesis. School of Engineering and Applied Science, Southern Methodist University] provide the basis for partitioning a social network by way of sparsest cuts and/or maximum concurrent flow.     

The professionalization of Spanish social work: moving closer to Europe or away from its roots?

This article will review the processes of professionalization of social work in Spain. With the advent of democratic Spain, many professions began a process of transformation. Those rooted in the relationship between the citizens, their rights and obligations, and the state, were among the first to be challenged. Social work was one of them. Soon thereafter, the European Union (EU), which Spain joined in 1986, brought forth greater challenges and incentives to change. In 1999, Spain and 29 other countries signed the Bologna Declaration, which committed the country to the development of a shared domain (often referred to as ‘espacio común’) with European higher education. This article reviews the historical process of insertion of social work, heavily influenced by the Catholic tradition of caring, into the universities. The paper examines the model of social work education in Spain, before and during Franco's era, and the professionalization (sometimes referred to as ‘tecnificación’) of care-giving and training-paradigms that followed the advent of democracy. Current models and efforts to bring Spanish social work into EU compliance have narrowed the gap with the Anglo-Saxon world; but have they distanced social work in Spain from its roots?     

Explicit Distributional Results In Pattern Formation II

The paper derives the joint generating function of a collection of pattern statistics associated with binary sequences. The models discussed cover independent and some dependent Bernoulli trials, including Markov dependent ones. The results cover, in particular, the moment generating function of the random search time for certain general binary patterns in the popular Knuth-Morris-Pratt algorithm and hence shed more light into its performance.     

Literacy Skills as an Explanation for Labor Market Imbalances by Occupational Type in Canada: Microsimulation Projections for 2014–2024

Population Research and Policy Review - In Canada, the immigration selection process gives great importance to education level. However, studies find that given an equivalent level of education,...     

Evaluating the local impacts of recent immigration to California: Realism versus racism

Although past migration was often viewed with suspicion the implicit assumption was that new migrants would fill the jobs in the growing cities and contribute to the national wealth. There are those who still subscribe to the view that continuing migration will increase national wealth, indeed that new migrants are the work horses of prosperity. There is another view however, which focuses on the local impacts of migration. This view suggests that the migrations of the late twentieth century are in a different context and create substantial burdens on local communities and states. It may be too, that the mass migrations of the late twentieth century will lead to a new pattern of social exclusion, polarization and a new ethnic under-class. The analysis of recent migration in California documents the extent to which that migration is made up of very low skill, low income, and dependent groups and has the potential to create significant local dependency burdens.     

A Two-Stage Estimator of the Dependence Parameter for the Clayton-Oakes Model

This paper describes the properties of a two-stage estimator of the dependence parameter in the Clayton-Oakes multivariate failure time model. The parameter is estimated from a likelihood function in which the marginal hazard functions are replaced by estimates. The method extends the approach of Shih and Louis (1995) and Genest, Ghoudi and Rivest (1995) to allow the marginal hazard for failure times to follow a stratified Cox (1972) model. The method is computationally simple and under mild regularity conditions produces a consistent, asymptotically normal estimator.     

Hold or fold?

This article examines some of the problems of the health care organizations we serve and that support us. While external problems can besiege an organization, the fundamental building block for success is to develop physician buy-in and a well-functioning team. The author describes how his IPA failed because the physicians in his organization didn't bond sufficiently, and for a sustained period, to carry out business operations. What are the warning signals that might help you decide whether to stay or move on? An IPA must have: (1) A clearly articulated vision of what success will look like, one that is accepted by its members; (2) effective leadership; (3) clear evidence of adaptability and flexibility; (4) financial stability; and (5) good data available to physicians. There can be other evidence of trouble you need to watch for. In some areas, hospitals and health plans are hostile to physician initiatives. Don't rely on politically motivated decisions--they are too easily changed. If you plan to be a leader for your physician organization, focus on creating or revising the internal architecture of the group.     

Mortality transition in the Ovamboland region of Namibia, 1930-1990

Few long-term statistical series exist that can document the mortality transition in Africa. This paper uses data from the parish registers of the Evangelical Lutheran Church in Namibia to study morality in Ovamboland between 1930 and 1990. The paper identifies significant discontinuities and reversals in the trend in mortality. Much of the mortality transition occurred in a rapid breakthrough concentrated between the early 1950s and early 1960s. Adult mortality fell more than existing model life tables would predict and the pattern of relatively high early-age mortality typical of modern Africa emerged only at this time. While a range of developments in Ovamboland contributed to the overall decline in mortality, the most important factor was the establishment, by the Finnish Mission, of a Western system of health care. In Ovamboland, the drive to 'good health at low cost' was articulated not through political institutions but through the church.     

Penalized image averaging and discrimination with facial and fishery applications

In this paper we use a penalized likelihood approach to image warping in the context of discrimination and averaging. The choice of average image is formulated statistically by minimizing a penalized likelihood, where the likelihood measures the similarity between images after warping and the penalty is a measure of distortion of a warping. The notions of measures of similarity are given in terms of normalized image information. The measures of distortion are landmark based. Thus we use a combination of landmark and normalized image information. The average defined in the paper is also extended by allowing random perturbation of the landmarks. This strategy improves averages for discrimination purposes. We give here real applications from medical and biological areas.