Bayesian unit-root tests for Stochastic Volatility models

In this article, we consider Bayesian inference procedures to test for a unit root in Stochastic Volatility (SV) models. Unit-root tests for the persistence parameter of the SV models, based on the Bayes Factor (BF), have been recently introduced in the literature. In contrast, we propose a flexible class of priors that is non-informative over the entire support of the persistence parameter (including the non-stationarity region). In addition, we show that our model fitting procedure is computationally efficient (using the software WinBUGS). Finally, we show that our proposed test procedures have good frequentist properties in terms of achieving high statistical power, while maintaining low total error rates. We illustrate the above features of our method by extensive simulation studies, followed by an application to a real data set on exchange rates.     

Mean estimation with data missing at random for functional covariables

In a missing-data setting, we want to estimate the mean of a scalar outcome, based on a sample in which an explanatory variable is observed for every subject while responses are missing by happenstance for some of them. We consider two kinds of estimates of the mean response when the explanatory variable is functional. One is based on the average of the predicted values and the second one is a functional adaptation of the Horvitz–Thompson estimator. We show that the infinite dimensionality of the problem does not affect the rates of convergence by stating that the estimates are root-n consistent, under missing at random (MAR) assumption. These asymptotic features are completed by simulated experiments illustrating the easiness of implementation and the good behaviour on finite sample sizes of the method. This is the first paper emphasizing that the insensitiveness of averaged estimates, well known in multivariate non-parametric statistics, remains true for an infinite-dimensional covariable. In this sense, this work opens the way for various other results of this kind in functional data analysis.     

The Past in the Present. Lessons on Semiotics of History from George H. Mead and Boris A. Uspensky

This article examines the parallels between George H. Mead's theory of time and Boris A. Uspensky's semiotics of history, looking for implications relevant to the symbolic interactionist theory of historical processes. It suggests that Mead's theory of time and theory of communication hold important implications for semiotic analysis of the historical dimension of sociocultural phenomena. A further aim is to link the symbolic interactionist tradition of the Chicago school with the Tartu school and its semiotics of history. This would fuel the further development of both theoretical orientations.     

Radio Free Europe and the Catholic Church in Poland During the 1950s and 1960s.

A review of the literature on Radio Free Europe’s role throughout the Cold War reveals its underdeveloped historiography. Yet, how valuable are RFE’s reports and broadcasts as a tool for historical exploration? Drawing on a wealth of materials from Polish programming, this analysis uses the case study of the role of the Catholic Church in Poland throughout the 1950s and the 1960s, to appraise not only the content of RFE reports but also the extent to which they can be used as a historical tool. The reports reveal, for example, that the Church became politically active already in the mid 1960s during its struggle with the Communist regime over the Millennium anniversary celebrations and the issue of Poland’s Western territories. This analytical framework allows for an examination of RFE’s comments in terms of what they might tell us about what really happened, and in terms of what they actually tell us about the station’s perceptions of what happened. The station’s position as an observer, critic and participant in the turmoil of the Cold War, gave it a distinct ability to access both the realities behind the Iron Curtain and the Western perceptions of what was happening in the satellite countries.     

A process capability index with reliable confidence intervals

A well-know process capability index is slightly modified in this article to provide a new measure of process capability which takes account of the process location and variability, and for which point estimator and confidence intervals do exist that are insensitive to departures from the assumption of normal variability. Two examples of applications based on real data are presented.     

The Determinants of Retail Productivity: A Critical Review of the Evidence

This paper discusses the literature on the established determinants of productivity in the retail sector. It also draws attention to some neglected strands of research which provide useful insights into strategies that could allow productivity enhancements in this area of the economy. To date, very few attempts have been made to integrate different specialisms in order to explain what drives productivity in retail. Here this paper rectifies this omission by putting together studies from economics, geography, knowledge management and employment studies. It is the authors’ view that quantitative studies of retail productivity should focus on total factor productivity in retailing as the result of competition/composition effects, planning regulations, information and communications technology, the multinational operation element and workforce skills. Further, the fact that retail firms possess advantages that are transferable between locations suggests that investment in strategies enhancing the transfer of explicit and tacit knowledge between and within businesses are crucial to achieve productivity gains.     

Hard evidence and ambiguity aversion

This article shows that if an allocation rule can be implemented with unlimited information certification, then it can also be implemented with limited information certification if the designer can use ambiguous communication mechanisms, and if agents are averse to ambiguity in the sense of maxmin expected utility. The reverse implication is true if there is a single agent and a worst outcome.     

Social Competence in Preschool Children: Replication of Results and Clarification of a Hierarchical Measurement Model

This study tested assumptions and conclusions reached in an earlier confirmatory factor analysis (CFA) study of the social competence (SC) construct for preschool children. Two samples (total N = 408; a new Portuguese sample and one from US samples that had participated in the original study) contributed data. Seven SC indicators were tested for mean differences across age, sex, and sample. Significant sex differences were found for peer acceptance (favoring girls) and for initiating affectively neutral interactions (boys had higher rates), and the sex by sample interaction also was significant for initiating interactions (i.e., effect significant only in the Portuguese sample). In CFAs, the hypothesized structure of SC fits the data and was invariant across sample and age within sample in both measurement and structural tests. The model was invariant at the measurement level for sex within sample tests, but not at the structural level. The results replicate and extend understandings of SC reported in the original study.     

The Satisfaction with Sex Life Across the Adult Life Span

Three separate issues concerning the relation between age and satisfaction with sex life are addressed in this article. The first issue was concerned with the age generalizability of the factor structure produced by responses to the Satisfaction with Sex Life Scale (SWSLS). The second issue was to examine whether there were differences in the satisfaction with sex life according to certain background characteristics, namely age. Finally, the relationship between scores on the SWSLS with those on other relational constructs was explored. Data collection involved completion of a questionnaire. The sample consisted of 1,144 participants. The mean ages of the sample were 38.99 years in (SD = 16.91); ages ranged from 20 to 80. The data indicated that the factor structure of responses to the SWSLS were highly similar through adult life. Religious involvement, marital status, and love status influenced satisfaction with sex life. Expected correlations with measures of other relationship constructs were found. The strongest predictor of satisfaction with sex live across the adult life span was love satisfaction. Suggestions concerning the use of the SWSLS for research and clinical purposes are offered.