Interpreting DNA Mixtures with Related Contributors in Subdivided Populations

Abstract.  In this paper, we study the statistical interpretation of forensic DNA mixtures with related contributors in subdivided populations. Compact general formulae for match probabilities are obtained for two situations: a relative of one tested person is an unknown contributor of a DNA mixture; and two related unknowns are contributors. The effect of kinship and population structure is illustrated using a real case example.     

Influence diagnostics and outlier tests for semiparametric mixed models

Summary. Semiparametric mixed models are useful in biometric and econometric applications, especially for longitudinal data. Maximum penalized likelihood estimators (MPLEs) have been shown to work well by Zhang and co-workers for both linear coefficients and nonparametric functions. This paper considers the role of influence diagnostics in the MPLE by extending the case deletion and subject deletion analysis of linear models to accommodate the inclusion of a nonparametric component. We focus on influence measures for the fixed effects and provide formulae that are analogous to those for simpler models and readily computable with the MPLE algorithm. We also establish an equivalence between the case or subject deletion model and a mean shift outlier model from which we derive tests for outliers. The influence diagnostics proposed are illustrated through a longitudinal hormone study on progesterone and a simulated example.     

Generalized Leverage and its Applications

The generalized leverage of an estimator is defined in regression models as a measure of the importance of individual observations. We derive a simple but powerful result, developing an explicit expression for leverage in a general M -estimation problem, of which the maximum likelihood problems are special cases. A variety of applications are considered, most notably to the exponential family non-linear models. The relationship between leverage and local influence is also discussed. Numerical examples are given to illustrate our results     

Online or Offline? Nonprofits’ Choice and Use of Social Media in Hong Kong

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Nonprofits are strategically using social media to disseminate information, engage with community, and mobilize...     

On moments and cumulants of the D compound Poisson distribution

This note provides more results on moments and cumulants of the D compound Poisson distribution through the properties of the multivariate generalized power series distribution.     

An analysis of two probabilistic model induction techniques

Two probabilistic model induction techniques, cart and constructor, are compared, via a series of experiments, in terms of their ability to induce models that are both interpretable and predictive. The experiments show that, although both algorithms are able to deliver classifiers with predictive performance close to that of the optimal Bayes rule,constructor is able to generate a probabilistic model that is more easily interpretable than the cart model. On the other hand, cart is a more mature algorithm and is capable of handling many more situations (e.g., real-valued training sets) thanconstructor. A variety of characteristics of both algorithms are compared, and suggestions for future research are made.     

The dependence of voter shares under a two-vote system

In an electoral system where each voter is allowed to select up to two candidates in a double-seat constituency, the combination of votes forms a special kind of contingency table. The usual hypothesis of complete independence of the voter shares for the candidates is of interest, but it is shown to be almost unattainable. The correlation coefficient of the voter shares is constructed. It is shown to be equivalent to Pearson's phi coefficient. The limitations of the coefficient are discussed. It is found that the use of conditional probabilities gives a better understanding of the dependence of the voter shares under the system considered.     

A more generalized stirling distribution of the second kind

A more generalized stirling distribution of the second kind (MGSDSK) is introduced in this paper as the distribution of the sum of the independent but not identically distributed left truncated Poisson variables. Properties of MGSDSK are studied. The recursion relation and decomposition of MGSDSK are obtained. The rth moment is also found and a new recurrence relationship for them are given. A new incomplete exponential function is utilized in the derivations. A MVU estimate of the p, d, f. of MGSDSK is obtained.     

A Comparison of Methods for Estimating the Benchmark Dose Based on Overdispersed Data from Developmental Toxicity Studies

Developmental anomalies resulting from prenatal toxicity can be manifested in terms of both malformations among surviving offspring and prenatal death. Although these two endpoints have traditionally been analyzed separately in the assessment of risk, multivariate methods of risk characterization have recently been proposed. We examined this and other issues in developmental toxicity risk assessment by evaluating the accuracy and precision of estimates of the effective dose ( ED ₀₅) and the benchmark dose ( BMD ₀₅) using computer simulation. Our results indicated that different variance structures (Dirichlet-trinomial and generalized linear model) used to characterize overdispersion yielded comparable results when fitting joint dose response models based on generalized estimating equations. (The choice of variance structure in separate modeling was also not critical.) However, using the Rao-Scott transformation to eliminate overdispersion tended to produce estimates of the ED ₀₅ with reduced bias and mean squared error. Because joint modeling ensures that the ED ₀₅ for overall toxicity (based on both malformations and prenatal death) is always less than the ED ₀₅ for either malformations or prenatal death, joint modeling is preferred to separate modeling for risk assessment purposes.     

WHAT MAKES THE LOCAL? A BRIEF CONSIDERATION OF THE REJUVENATION OF HONG KONG IDENTITY

This paper ascertains what makes the local and why the local is important, in the context of change in Hong Kong due to the political transition to PRC sovereignty.In doing so, I hope to pose a modest polemical challenge to cultural studies' tendency to overlook seemingly simplistic empirical information. The return of Hong Kong to China in 1997 has led to a contraction of the political sphere, as the convergence of political structures curbed the development of local identities. The label or category ‘Hong Kong people’ was then appropriated with a specific meaning for the local to resist encroachment of the national. It was true that the high intensity of dominant national discourses during the political transition created a favourable atmosphere for re-nationalization. However, as soon as the political transition was over, Hong Kongers re-adhered to their own label in their struggle for cultural autonomy.Their strong cultural affect toward various national icons during the transition quickly diminished. This multiyear discourse study (1996–1998), which utilizes social scientific methods in conjunction with cultural theories, illustrates important political and methodological impulses necessary for the formulation of a socio-political approach to cultural studies within the Hong Kong context.