SMOOTH TRANSITION AUTOREGRESSIVE MODELS — A SURVEY OF RECENT DEVELOPMENTS

This paper surveys recent developments related to the smooth transition autoregressive (STAR) time series model and several of its variants. We put emphasis on new methods for testing for STAR nonlinearity, model evaluation, and forecasting. Several useful extensions of the basic STAR model, which concern multiple regimes, time-varying non-linear properties, and models for vector time series, are also reviewed.     

Use of Various Health Care Services by Students in Helsinki

Abstract

Review of the working of various health care schemes has revealed predominant use by a certain group of “large-scale consumers.” The concomitant use of various services (health, dental, and mental health care) was studied within the Helsinki Health Center of the Finnish Student Health Service from January 1, 1980 to August 31, 1980. The group consisted of 16,174 students. The characteristics of the groups of patients who used only the mental health care service and of those who used all three services were also studied. Within each sector, there were fewer patients than expected who did not use the services of other sectors. The number of patients visiting dental and health care services, mental health and health care services, and all three services were greater than expected. The groups of patients who used only the mental health care service and those who used all three services were surprisingly similar. The greatest difference between the groups probably lay in their need for somatic and dental care. The organization, which incorporates mental health, dental, and health care services in the same building offers improved possibilities for care of the patient as a whole. On the basis of this study, there is no reason to think that such an organization leads to misuse of the various services.     

Forecasting Macroeconomic Variables Using Neural Network Models and Three Automated Model Selection Techniques

When forecasting with neural network models one faces several problems, all of which influence the accuracy of the forecasts. First, neural networks are often hard to estimate due to their highly nonlinear structure. To alleviate the problem, White (2006 White, H. (2006). Approximate nonlinear forecasting methods. In: Elliott, G. Granger, C. W. J. Timmermann, A. eds. Handbook of Economic Forecasting, volume 1, Amsterdam:Elsevier, pp. 459–512.[Crossref] , [Google Scholar]) presented a solution (QuickNet) that converts the specification and nonlinear estimation problem into a linear model selection and estimation problem. We shall compare its performance to that of two other procedures building on the linearization idea: the Marginal Bridge Estimator and Autometrics. Second, one must decide whether forecasting should be carried out recursively or directly. This choice is investigated in this work. The economic time series used in this study are the consumer price indices for the G7 and the Scandinavian countries. In addition, a number of simulations are carried out and results reported in the article.     

Conditional Correlation Models of Autoregressive Conditional Heteroscedasticity With Nonstationary GARCH Equations

In this article, we investigate the effects of careful modeling the long-run dynamics of the volatilities of stock market returns on the conditional correlation structure. To this end, we allow the individual unconditional variances in conditional correlation generalized autoregressive conditional heteroscedasticity (CC-GARCH) models to change smoothly over time by incorporating a nonstationary component in the variance equations such as the spline-GARCH model and the time-varying (TV)-GARCH model. The variance equations combine the long-run and the short-run dynamic behavior of the volatilities. The structure of the conditional correlation matrix is assumed to be either time independent or to vary over time. We apply our model to pairs of seven daily stock returns belonging to the S&P 500 composite index and traded at the New York Stock Exchange. The results suggest that accounting for deterministic changes in the unconditional variances improves the fit of the multivariate CC-GARCH models to the data. The effect of careful specification of the variance equations on the estimated correlations is variable: in some cases rather small, in others more discernible. We also show empirically that the CC-GARCH models with time-varying unconditional variances using the TV-GARCH model outperform the other models under study in terms of out-of-sample forecasting performance. In addition, we find that portfolio volatility-timing strategies based on time-varying unconditional variances often outperform the unmodeled long-run variances strategy out-of-sample. As a by-product, we generalize news impact surfaces to the situation in which both the GARCH equations and the conditional correlations contain a deterministic component that is a function of time.     

Educational attainment and employment of young adults ageing out of care: A registry study based on the Finnish birth cohort 1987

Adolescents growing up outside their birth homes are at major risk for multiple adversities in early adulthood, including low education and unemployment. The transition from out-of-home placement to independent living overlaps with the transition from school to work and higher education. However, the support during this critical phase is often inadequate. Adolescents ageing out of care are also more likely to have faced adversities in their birth families. Yet, the interplay between different risk factors and having aged out of care has gained little attention. This study aimed to assess known risk factors for low education and unstable employment and their interaction with ageing out of care, controlling for birth-home-related adversities. We assessed this topic using logistic and linear regression modelling based on the Finnish birth cohort 1987 (n = 59 476) registry. Our analysis showed that obtaining upper secondary and higher education was much less likely among those ageing out of care, and they had spent 52–80 fewer days annually in employment after graduation. Few interactions with other risk factors were, however, found. Efforts are needed to prevent inequalities in education and employment for those ageing out of care in the transition phase from school to work.     

Vegetated roofs in boreal climate support mobile open habitat arthropods,with differentiation between meadow and succulent roofs

Urban Ecosystems - Vegetated roofs are hoped to benefit urban wildlife, yet there are few empirical results regarding the conservation potential of such roofs. In this paper, we focus on arthropods...     

Perceptions of Justice in the Making: Rescaling of Customary Law in Post-Suharto Maluku,Indonesia

This article questions how successful neo-traditional law has been in providing access to justice to Kei Islanders of Maluku, Eastern Indonesia during recent political transitions. It describes the prevailing model of justice in which traditional law draws some of its authority from the state but provides its own normative framework for addressing community disputes. After the fall of Suharto's New Order regime, people began to apply neo-traditional law to ethnic and resource conflicts, arguing that it took precedence over state law in these emerging domains. Although the neo-traditionalist revival affirmed the autonomy of traditional legal institutions, actual legal procedures and outcomes depended on the response of state authorities and national publics to newly activated traditional normative frameworks. The politics of legality in post-Suharto Indonesia have produced increasingly state-oriented models of justice, but legal outcomes still determine the choice between different normative frameworks.     

Anerkennung der beruflichen Kompetenzen von Flüchtlingen – Ein Beitrag zur IntegrationRecognition of professional competences of refuges – a contribution to their integration

In the coming years the integration of refugees in Germany will be a major challenge. The paper initially employs psychological theories, such as the self-determination theory, social identity theory and latent functions of employment, to reveal why the integration of refugees into the national labor market is an important factor for their integration into society as a whole. The labor market, confronting a shortage of skilled professionals caused by demographic change, shows a high potential for the integration of refugees. However, it appears that formal requirements in the current recognition process of occupational qualifications, for example in the craft industry, are still very high. The paper describes – on the basis of case studies – an optimized recognition process of occupational qualifications, in which, in addition to the mere checking of documents, the professional competences among the refugees are assessed on site at the business.     

Family support services buffer the effect of child welfare notifications on child removals

Previous studies have found mixed results about the effects of family support services within the child protection system. The purpose of the study is to examine whether family support services are associated with the need for child removals at the community level. The material of the study consists of Finnish municipalities (N = 292) and their child protection indicators. Linear regression analysis was conducted to analyse the associations between the dependent variable (child removals) and the main predictors (child welfare notifications and family support services). It was found that family support services are associated with child removals. The more children there are in family support services, the more there are also child removals in a municipality. The key finding of the analysis is that a higher rather than lower proportion of clients in family support services buffers the increased effect of demand (child welfare notifications) on child removals better. In this sense, the demand for child removals is not only associated with the characteristics of children and families but may be partly explained by the role of family support services in a municipality. The present study underlines the significance of a system-level approach to child protection.