Wavelet semi-parametric inference for long memory in volatility in the presence of a trend

Risk of investing in a financial asset is quantified by functionals of squared returns. Discrete time stochastic volatility (SV) models impose a convenient and practically relevant time series dependence structure on the log-squared returns. Different long-term risk characteristics are postulated by short-memory SV and long-memory SV models. It is therefore important to test which of these two alternatives is suitable for a specific asset. Most standard tests are confounded by deterministic trends. This paper introduces a new, wavelet-based, test of the null hypothesis of short versus long memory in volatility which is robust to deterministic trends. In finite samples, the test performs better than currently available tests which are based on the Fourier transform.     

Change-Point Detection With Non-Parametric Regression

We consider the regression model y_i = ?(x_i ) + ε in which the function ? or its pth derivative ?^(p) may have a discontinuity at some unknown point τ. By fitting local polynomials from the left and right, we test the null that ?^(p) is continuous against the alternative that ?^(p)(τ?) ≠ ?^(p)(τ+). We obtain Darling-Erdös type limit theorems for the test statistics under the null hypothesis of no change, as well as their limits in probability under the alternative. Consistency of the related change-point estimators is also established.     

Władysław Konopczyński: a Polish Historian of European Caliber

Władysław Konopczyński, a Polish scholar and an investigator of modern history, certainly deserves to be recalled and to reappear yet again in all-European awareness. It must be done due to the fact that the name of that very outstanding and titled pre-war scholar was forced to disappear completely from the European humanities for fifty years. The decision of expelling Konopczyński from the world of European historians was made by the communist leaders of Poland. However, before that time, Konopczyński had played an important role in Europe. It is just enough to mention that during Poland's twenty years of independence after World War I, in the year 1931, Konopczyński was granted a membership in the Royal Swedish Academy of Sciences in Stockholm. Moreover, he was awarded the Swedish Royal Order of the Polar Star and the French Legion of Honour. Furthermore, the historian participated in many international congresses and his works were printed in many countries of Western Europe. In 1947 in Stockholm the heir to the throne himself attended Konopczyński's lecture. An erratum to this article is available at .     

The Mystery of the European Smile: A Comparison Based on Individual Photographs Provided by Internet Users

The aim of the study was to analyze cross-cultural differences in preference for smiling among the users of one of the most popular instant messaging sites called Windows Live Messenger in terms of facial expression (smiling vs. non-smiling) on the photographs accompanying their profiles. 2,000 photos from 10 countries were rated by two independent judges. Despite the fact that 20 years have passed since the fall of the Berlin Wall, Internet users from a former Soviet bloc appear to smile less often than those from Western Europe. Also, replicating past research, women irrespective of their nationality smiled more than men.     

Parental perceptions of the Children In Need Of Treatment dental program

This paper discusses the collaborative partnership involving the Middlesex-London Public Health Research, Education and Development site, the Ontario Ministry of Health Promotion and Sport, then Chronic Disease Prevention and Health Promotion Branch, and an academic institution in the first-ever research of parental perceptions of the Children In Need Of Treatment. This paper provides an overview of the Children In Need Of Treatment program, reviews the results of the research (a mailed, self-administered survey with a systematic random sample of parents from three health units whose children received dental treatment that was paid by Children In Need Of Treatment in 2006), and its subsequent recommendations. How these recommendations affected program planning and policy are examined. In conclusion, parents were very satisfied with the treating dentist and the Children In Need Of Treatment program, and found Children In Need Of Treatment to be vital in addressing the health of their children by attending to their urgent dental needs.     

Social welfare in the light of topic modelling

With an increased focus on social well-being in response to a burgeoning global economy exposing the weaknesses of social welfare policies, research output in the field has grown exponentially. Keeping track of the evolving research themes proves difficult due to the steady rise in the number of studies published in the interdisciplinary field of social welfare. Therefore, researchers need a comprehensive overview to confirm the current shape of the field based on the published research. Using a latent Dirichlet allocation algorithm as a topic modelling technique, this study identified 12 prominent themes from more than 10,000 research outputs on social welfare published from 2000 to 2020 in Scopus-indexed journals. Such an exploratory text-mining approach to literature review provides broad insights into the diversity of research and may serve as a foundation for further in-depth studies. Identifying these 12 thematic areas and their sub-themes allows us to articulate the complexity and diversity of social welfare issues, which go far beyond the field of well-established welfare economics or social work. The study shows that the topic of ‘social welfare’ has not only evolved over time but has significantly broadened its meaning. It can no longer be solely synonymous with institutional social security. We contend that research in this area needs to take into account a broader and more systematic range of determinants constituting the dynamic character of social welfare.