Specification and testing of multiplicative time-varying GARCH models with applications

In this article, we develop a specification technique for building multiplicative time-varying GARCH models of Amado and Teräsvirta (2008, 2013). The variance is decomposed into an unconditional and a conditional component such that the unconditional variance component is allowed to evolve smoothly over time. This nonstationary component is defined as a linear combination of logistic transition functions with time as the transition variable. The appropriate number of transition functions is determined by a sequence of specification tests. For that purpose, a coherent modelling strategy based on statistical inference is presented. It is heavily dependent on Lagrange multiplier type misspecification tests. The tests are easily implemented as they are entirely based on auxiliary regressions. Finite-sample properties of the strategy and tests are examined by simulation. The modelling strategy is illustrated in practice with two real examples: an empirical application to daily exchange rate returns and another one to daily coffee futures returns.     

A Postmodern Critique of Societal Discourses of Male Violence in Interpersonal Family Relationships: A Balancing Act for Social Work

In recent years, treatments of family violence have tended to be built around conventional discourses suggesting that men are major initiators in instances of interpersonal violence. Utilizing a postmodernist analysis, we assess societal discourses that continue to give life to this narrow conceptualization of interpersonal violence. We also examine literature suggesting that both men and women resort to violence to resolve relationship difficulties and suggest that a more holistic and inclusive approach to understanding interpersonal violence is critical for social workers committed to social justice and a balanced understanding of the contextual nature of human problems.     

Rainfall variations and child mortality in the Sahel: results from a comparative event history analysis in Burkina Faso and Mali

Over the last 40 years, the Sahel has seen a long-term downward trend in rainfall. The importance of ecological variables as factors affecting child survival in rural subsistence societies has already been emphasized, but little empirical evidence has been gathered to support this. This paper presents a comparative event history analysis aimed at understanding how rainfall variations may influence child mortality in two neighbouring countries, Burkina Faso and Mali. These countries are similar in terms of population dynamics, economy, livelihood, child mortality and rainfall conditions (i.e. strong south–north decreasing rainfall gradient). Individual data for both countries came from two detailed nationally representative retrospective surveys conducted in 2000. Rainfall data for the 1960–1998 time period were obtained from the Climatic Research Unit. This study shows that child survival in each country is related to specific patterns of rainfall variation across livelihood regions, highlighting the complex nature of environmental causality of child mortality.     

On computer generation of gamma random variables by rejection and composition procedures 2

The paper presents various algorithms for generating gamma random variables, by combining rejection and composition procedures. Two efficient algorithms are given for the case when the parameter of the gamma distribution is 0<v<l. For the case vl, several algorithms are given but they (except one), work reliably only for small values of v. Results of some computer tests together with FORTRAN subroutines are also presented.     

Attentional Bias in Problem Gambling: A Systematic Review

Attentional bias has been the subject of extensive empirical investigation in connection with chemical addictions, and it has been demonstrated in users of several different substances. The findings show that substance users seem to notice and attend to substance-related stimuli more readily than non-substance-related stimuli. Less is known, however, about attentional bias in pathological gambling. This systematic review investigates the existing empirical evidence on attentional bias in problem and pathological gamblers. Eleven studies were identified and evaluated following a literature search. Key findings are that problem and pathological gamblers seem to exhibit attentional bias toward gambling-related stimuli across different measuring paradigms, although some negative findings were reported. Recommendations aimed at improving research on this topic include better validation of measures, the inclusion of manipulations of craving level, and adding variations in gambling severity as a variable, as well as gambling preference. Research on therapeutic procedures aimed at reducing attentional bias is also recommended.     

Co-Production in the Context of Finnish Social Services and Health Care: A Challenge and a Possibility for a New Kind of Democracy

Alongside the ongoing renewal process of the Finnish welfare state, the role of the citizens is also revisited. So far the attention has mainly focused on how the responsibility for service provision is shared between the public sector and the service users, while the role of public services as a part of the democratic system has been more or less ignored. Based on the results from a 3-year participatory action research project called KAMPA, this article will discuss if the development of co-production in the context of public welfare services shows the way forward toward a new kind of society where democracy is an inseparable part of the structures and procedures of the service provision. The data gathered during the project (textual material, interviews, notes from meetings, and observation diaries) are analyzed using thematic analysis. The results show that while legislation and official policies strongly highlight the participation of citizens and service users, there are still many obstacles to overcome at both the attitudinal and practical level. The development of co-production and arenas of a new kind of democracy requires continuity in the attempts and recognition of the achievements, but it also has the potential to demonstrate the way in which a new more lively democratic society can come true in practice.     

Compensation or Reinforcement? The Stratification of Parental Responses to Children’s Early Ability

Theory and empirical evidence suggest that parents allocate their investments unequally among their children, thus inducing within-family inequality. We investigate whether parents reinforce or compensate for initial ability differences between their children as well as whether these parental responses vary by family socioeconomic status (SES). Using the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B) and a twin fixed-effects approach to address unobserved heterogeneity, we find that parental responses to early ability differences between their children do vary by family SES. Contrary to prior findings, we find that advantaged parents provide more cognitive stimulation to higher-ability children, and lower-class parents do not respond to ability differences. No analogous stratification in parental responses to birth weight is found, suggesting that parents’ responses vary across domains of child endowments. The reinforcing responses to early ability by high-SES parents do not, however, led to increases in ability differences among children because parental responses have little effect on children’s later cognitive performance in this twin sample.     

Generationenabfolge – ein Faktor des Wandels in Modernisierungsprozessen. Shmuel N. Eisenstadts Beitrag zur Generationensoziologie

This paper will highlight to what extend Eisenstadt’s theory connects to the approach of historic generations. At first, his early comparative work “From Generation to Generation” is reconstructed. In this book, Eisenstadt presents a model of generations based on structural-functionalist assumptions; he conceptualizes the relation between generations and social change as a problem of system integration of specific age-groups on the one hand and the regulation of tensions between these groups on the other hand. Using the youth- and student movements as an example, this article shows how Eisenstadt’s interpretations change with the development of his theory. In the second part of this paper, it will be proposed how his approach can be developed further by interlocking his concept more closely with Mannheim’s theory of generations as well as other recent findings of socialization theory. It will furthermore be discussed, how his modernization theory has the potential to solve a theoretical problem inherent in Mannheim’s approach.     

A Characterization of a Matric-Variate Exponential Distribution

Suppose S is a positive definite m x m random matrix and S> Ω denotes the event that S—Ω is positive definite, Ω being a constant positive definite matrix. Under very mild regularity conditions, we show that the constraint Pr(S>Ω₁+Ω₂ | S>Ω₂) = Pr(S>Ω₁) implies that S has a Wishart distribution on m+ 1 degrees of freedom.