Model selection for factor analysis: Some new criteria and performance comparisons

This paper derives Akaike information criterion (AIC), corrected AIC, the Bayesian information criterion (BIC) and Hannan and Quinn’s information criterion for approximate factor models assuming a large number of cross-sectional observations and studies the consistency properties of these information criteria. It also reports extensive simulation results comparing the performance of the extant and new procedures for the selection of the number of factors. The simulation results show the di?culty of determining which criterion performs best. In practice, it is advisable to consider several criteria at the same time, especially Hannan and Quinn’s information criterion, Bai and Ng’s IC_p2 and BIC₃, and Onatski’s and Ahn and Horenstein’s eigenvalue-based criteria. The model-selection criteria considered in this paper are also applied to Stock and Watson’s two macroeconomic data sets. The results differ considerably depending on the model-selection criterion in use, but evidence suggesting five factors for the first data and five to seven factors for the second data is obtainable.     

A comparative study of confidence intervals to assess biosimilarity from analytical data

Assessment of analytical similarity of tier 1 quality attributes is based on a set of hypotheses that tests the mean difference of reference and test products against a margin adjusted for standard deviation of the reference product. Thus, proper assessment of the biosimilarity hypothesis requires statistical tests that account for the uncertainty associated with the estimations of the mean differences and the standard deviation of the reference product. Recently, a linear reformulation of the biosimilarity hypothesis has been proposed, which facilitates development and implementation of statistical tests. These statistical tests account for the uncertainty in the estimation process of all the unknown parameters. In this paper, we survey methods for constructing confidence intervals for testing the linearized reformulation of the biosimilarity hypothesis and also compare the performance of the methods. We discuss test procedures using confidence intervals to make possible comparison among recently developed methods as well as other previously developed methods that have not been applied for demonstrating analytical similarity. A computer simulation study was conducted to compare the performance of the methods based on the ability to maintain the test size and power, as well as computational complexity. We demonstrate the methods using two example applications. At the end, we make recommendations concerning the use of the methods.     

Diagnostics of multiple group influential observations for logistic regression models

In this paper, two new multiple influential observation detection methods, GCD.GSPR and mCD*, are introduced for logistic regression. The proposed diagnostic measures are compared with the generalized difference in fits (GDFFITS) and the generalized squared difference in beta (GSDFBETA), which are multiple influential diagnostics. The simulation study is conducted with one, two and five independent variable logistic regression models. The performance of the diagnostic measures is examined for a single contaminated independent variable for each model and in the case where all the independent variables are contaminated with certain contamination rates and intensity. In addition, the performance of the diagnostic measures is compared in terms of the correct identification rate and swamping rate via a frequently referred to data set in the literature.     

Du machisme au coparentage: pour une révolution des mentalités en Italie

Cet article décrit les processus législatifs et judiciaires complexes nécessaires pour que le droit au coparentage s'impose dans le droit du travail italien. Après avoir expliqué que le système juridique italien a jusqu'à présent assimilé la protection de la famille à la seule protection de la femme et de la maternité, l'auteur décrit l'évolution législative qui a permis de reconnaître aux pères un rôle fondamental dans l'éducation des enfants. Il montre ensuite que la jurisprudence, en retenant une interprétation moderne des principes inscrits dans la loi, contribue à vaincre la résistance à une telle évolution dans une société encore marquée par la domination masculine.     

On Hotelling’s T2 test in a special paired sample case

In a special paired sample case, Hotelling’s T² test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.     

Estimation of the smallest scale parameter of two-parameter exponential distributions

Improved point and interval estimation of the smallest scale parameter of n independent populations following two-parameter exponential distributions are studied. The model is formulated in such a way that allows for treating the estimation of the smallest scale parameter as a problem of estimating an unrestricted scale parameter in the presence of a nuisance parameter. The classes of improved point and interval estimators are enriched with Stein-type, Brewster and Zidek-type, Maruyama-type and Strawderman-type improved estimators under both quadratic and entropy losses, whereas using as a criterion the coverage probability, with Stein-type, Brewster and Zidek-type, and Maruyama-type improved intervals. The sampling framework considered incorporates important life-testing schemes such as i.i.d. sampling, type-II censoring, progressive type-II censoring, adaptive progressive type-II censoring, and record values.     

The role,importance and challenges of social sciences and humanities in the work of the intergovernmental science-policy platform on biodiversity and ecosystem services (IPBES)

Qualified competences in social science and humanities are required across the various deliverables of the intergovernmental science-policy platform on biodiversity and ecosystem services (IPBES) in order to fully address the objectives of IPBES. Building integrative approaches has long been acknowledged as a scientific challenge. Hence, new paths have to be forged, including revisiting basic ontological and epistemological considerations, such as how we understand the world, what knowledge is, and the role of science. Constructive interdisciplinary dialogues in IPBES supports the development of innovative frames and terminologies. One example is the evolution from the Millennium Ecosystem Assessment ecosystem service framework to the Nature’s Contributions to People classification now applied in IPBES assessments. IPBES is still in a learning phase and critical examination of what is accomplished this far is useful when refining ongoing modes of work and in long-term strategic considerations.     

Linking family engagement with a rights perspective: macro factors influencing practice

While child welfare practitioners in many countries are struggling to develop methods of effective family engagement, they operate within different national and cultural contexts that influence, both positively and negatively, the ability to engage with families. Increasingly, international comparisons are necessary to further understanding of the development of social work practice. This is particularly necessary because most countries utilize international frameworks (such as the United National Convention on the Rights of the Child) to provide guidance in the development of policies, programs, and interventions. Each country (and locality) struggles to advance practice to be more effective and humane. Our paper offers a comparative analysis focused on family-oriented and rights-based frameworks of different countries. Based on a review of current national policies and a review of the literature regarding family-based practices, we examine similarities and differences among four countries: the United Kingdom, Sweden, the United States, and South Korea. These countries were selected because they have some similarities (advanced industrialized democracies, professional social work, and formal child protection systems) but have some differences in their social welfare systems (policies, specific practices, and socio-cultural context). These differences can be utilized to advance understanding regarding the promise and potential for family engagement strategies. We then discuss the utility of this comparison for theory-building in the arena of child-care practice and conclude by identifying the challenges and limitations of this work.     

Anti-hierarchical activism in Hong Kong: the post-80s youth

In 2009, a political youth movement known as the Post-80s emerged in Hong Kong to protest against the construction of a high-speed railway. While local academics and government officials framed the motivations of these youth protesters using economic rationales, I argue here that the Post-80s are better understood as conveying their dissatisfaction towards existing political structures in the city. This profile sets out Post-80s criticisms of the entrenched hierarchical dynamics in Hong Kong political culture that has shaped interactions between the government, political parties and the wider population, and discusses how the Post-80s have responded to the representational imbalances imposed by these hierarchical practices in the local political sphere by advocating for a way of doing politics where individual voices (as opposed to the collective) are emphasized, and where horizontal structures are used. I conclude by exploring the repercussions of this critique on recent political discourses and protests observed in Hong Kong.     

Examples of practice: an intercultural approach to translate Romanian children’s folklore into Spanish

Due to the great number of Romanian pupils in Spanish public school, the local administration organises extra-curricular Romanian courses in order to preserve the Romanian language and culture. This is a way to contribute to build and consolidate a bicultural and bilingual profile of the young people. Besides, it is also an opportunity to align with plurilingual and pluricultural competence established by The Common European Framework of References for Languages (2002). Based on the premise that “children's literature is an intercultural instrument”, I choose as corpus the Romanian children's folklore represented by games, formula-songs, recital-stories, household words, incantations, riddles and lullabies to translate into Spanish. After the translations, Romanian children had to find similarities and differences between the Romanian and Spanish children's songs, in order to augment the knowledge about both cultures.