Age Is But a Number? An Exploration of Age Differences in Episodic Volunteering

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Age has long been understood as a strong demographic determinant of volunteering. However, to date, limited literature...     

A new long-term survival model with dispersion induced by discrete frailty

Lifetime Data Analysis - Frailty models are generally used to model heterogeneity between the individuals. The distribution of the frailty variable is often assumed to be continuous. However, there...     

Inference and Decision Making for 21st-Century Drug Development and Approval

ABSTRACT

The cost and time of pharmaceutical drug development continue to grow at rates that many say are unsustainable. These trends have enormous impact on what treatments get to patients, when they get them and how they are used. The statistical framework for supporting decisions in regulated clinical development of new medicines has followed a traditional path of frequentist methodology. Trials using hypothesis tests of “no treatment effect” are done routinely, and the p-value < 0.05 is often the determinant of what constitutes a “successful” trial. Many drugs fail in clinical development, adding to the cost of new medicines, and some evidence points blame at the deficiencies of the frequentist paradigm. An unknown number effective medicines may have been abandoned because trials were declared “unsuccessful” due to a p-value exceeding 0.05. Recently, the Bayesian paradigm has shown utility in the clinical drug development process for its probability-based inference. We argue for a Bayesian approach that employs data from other trials as a “prior” for Phase 3 trials so that synthesized evidence across trials can be utilized to compute probability statements that are valuable for understanding the magnitude of treatment effect. Such a Bayesian paradigm provides a promising framework for improving statistical inference and regulatory decision making.     

Anmerkungen zur Publikation „Möglichkeiten und Probleme des Einsatzes postalischer Befragungen“ von Karl-Heinz Reuband in der Kzfss 2001, 2, S. 307–333

Reuband’s article purports to report empirical results that seem to contradict the widely held view of mail surveys. This assertion is made possible only by an unclear statement of hypotheses and a selective perception of the literature. The data analysis is based on techniques from the 1960s and 1970s; modern methods are not even mentioned. Although all the results reported in the article are based on local surveys conducted by a university institute, these are generalized to national surveys in general. The main points of this critique are methodological: careless literature review, lack of concrete hypotheses, inefficient data analysis and generalizations without empirical foundation.     

Determinanten regelkonformen Verhaltens am beispiel des Strassenverkehrs

The main role of traffic police enforcement can be seen as preventing road users from committing offences, which can be related to road crashes and injuries. As the operating principle underlying the impact of police enforcement a deterrence effect has been discussed repeatedly, whereas from a sociological perspective the importance of “Norm Internalisation” has been emphasised. Thus, the present paper aims at comparing the influence of “Norm Internalisation” and the variables constituting the deterrence effect on the compliance with rules in road traffic. Based on a secondary analysis of data from a project on behavioural determinants of police surveillance carried out by the “Institute of Applied Transport and Tourism Research” (IVT) on behalf of the Federal Highway Research Institute (BASt) an operationalisation of the construct “General Norm Orientation” is developed. In several subsequent steps of statistical analysis patterns of correlations with variables from Opp’s “Theory of Law Obedience” are revealed. Results show a sufficiently high internal consistency (α = 0,82) of the scale “General Norm Orientation” and significant correlations with variables from Opp’s theory. The directions of these correlations are as expected and confirmed by multivariate analyses. Results are discussed with respect to their implications for influencing road users’ behaviours.     

Measures of Multigroup Segregation

In this paper we derive and evaluate measures of multigroup segregation. After describing four ways to conceptualize the measurement of multigroup segregation—as the disproportionality in group (e.g., race) proportions across organizational units (e.g., schools or census tracts), as the strength of association between nominal variables indexing group and organizational unit membership, as the ratio of between–unit diversity to total diversity, and as the weighted average of two–group segregation indices—we derive six multigroup segregation indices: a dissimilarity index (D), a Gini index (G), an information theory index (H), a squared coefficient of variation index (C), a relative diversity index (R), and a normalized exposure index (P). We evaluate these six indices against a set of seven desirable properties of segregation indices. We conclude that the information theory index H is the most conceptually and mathematically satisfactory index, since it alone obeys the principle of transfers in the multigroup case. Moreover, H is the only multigroup index that can be decomposed into a sum of between– and within–group components.     

Frustration in Infancy: Implications for Emotion Regulation,Physiological Processes,and Temperament

A study sample of 162 six‐month‐old children was selected from a larger sample of 346 infants on the basis of parents' report of their infants' temperament and a laboratory assessment of temperament. Infants were classified as easily frustrated and less easily frustrated and compared on a number of emotion regulation, physiology, and temperament measures. Results indicated that male and female infants were equally likely to be classified as frustrated and less easily frustrated; however, male infants were less able to regulate physiologically. Easily frustrated infants used different emotion regulation strategies and were observed to be less attentive and more active than less easily frustrated infants when observed in the laboratory. These infants were also characterized by their parents as more active, less attentive, and more distressed to novelty. Infants classified as easily frustrated were more reactive physiologically and less able to regulate physiological reactivity than their less easily frustrated counterparts. It is hypothesized that this cluster of characteristics may constitute a unique temperamental type that may have implications for other types of behavioral functioning. Limitations of the study are that observations are based on a single brief assessment of the infant, modest effect sizes were found, and the study is cross‐sectional.