Pretest-posttest designs and measurement of change

The article examines issues involved in comparing groups and measuring change with pretest and posttest data. Different pretest-posttest designs are presented in a manner that can help rehabilitation professionals to better understand and determine effects resulting from selected interventions. The reliability of gain scores in pretest-posttest measurement is also discussed in the context of rehabilitation research and practice.     

Factor Multivariate Stochastic Volatility via Wishart Processes

This paper proposes a high dimensional factor multivariate stochastic volatility (MSV) model in which factor covariance matrices are driven by Wishart random processes. The framework allows for unrestricted specification of intertemporal sensitivities, which can capture the persistence in volatilities, kurtosis in returns, and correlation breakdowns and contagion effects in volatilities. The factor structure allows addressing high dimensional setups used in portfolio analysis and risk management, as well as modeling conditional means and conditional variances within the model framework. Owing to the complexity of the model, we perform inference using Markov chain Monte Carlo simulation from the posterior distribution. A simulation study is carried out to demonstrate the efficiency of the estimation algorithm. We illustrate our model on a data set that includes 88 individual equity returns and the two Fama-French size and value factors. With this application, we demonstrate the ability of the model to address high dimensional applications suitable for asset allocation, risk management, and asset pricing.     

Multivariate methods in rehabilitation

The complexity of relationships between variables in a variety of rehabilitation settings can be appropriately addressed by the use of multivariate methods of statistical analysis. The purpose of this article is to describe (a) some basic concepts and principles of multivariate methods as well as (b) common misconceptions in the application of such methods. Specifically, the authors focus on the use of multivariate analysis of variance (MANOVA) in rehabilitation research and some pitfalls that rehabilitation researchers face when choosing between MANOVA for a set of outcome variables versus separate analyses of variance (ANOVAs) for each outcome variable. Examples of the use of MANOVA in rehabilitation research, as well as references to other multivariate methods, are also provided.     

Variance effects in the bongaarts-feeney formula

Bongaarts and Feeney have recently proposed an adjusted total fertility rate to disentangle tempo effects from changes in the quantum of fertility. We propose an extension to the Bongaarts and Feeney formula that includes variance effects: that is, changes in the variance of the fertility schedule over time. If these variance effects are ignored, the mean age at birth and the adjusted total fertility rate are biased. We provide approximations for these biases, and we extend the TFR adjustment to fertility schedules with changing variance. We apply our method to the Swedish baby boom and bust, and show that variance effects are important for evaluating the relative contributions of tempo and quantum effects to the fertility change from 1985 to 1995.     

The Effect of Competing Intentions and Behaviour on Short-Term Childbearing Intentions and Subsequent Childbearing

This article examines the effect that intentions to start studying and to enter into employment may have on childbearing intentions and subsequent childbearing. The analysis also includes the impact of the corresponding behaviour: currently studying or being employed. The theoretical background draws on Barber’s study of competing attitudes, with an emphasis on competing intentions. Based on survey and register data for Bulgaria, the analyses reveal the effect of competing intentions. For example, the intention to start studying hampers the construction and subsequent realisation of intentions to have a child within 2 years. The actual behaviour of currently studying has the same effect; both effects are most pronounced for intentions to become a parent and for actual entry into parenthood. Inversely, an intention to enter into employment facilitates childbearing intentions and, for men, so does the behaviour of being employed. The latter result holds for women’s intention to have a second child. The findings indicate that when childbearing intentions and realisation are analysed, it is preferable to consider persons with a competing intention to start studying either as a separate group or group them with those who are currently studying, not with those who are not. Logistic regression models and interaction effects are applied for the analyses.     

Tempo Effects in the Fertility Decline in Eastern Europe: Evidence from Bulgaria, the Czech Republic, Hungary, Poland, and Russia

A recent formula due to Bongaarts and Feeney allows us todisentangle tempo and quantum effects in changes of the totalfertility rate. This article applies the TFR adjustment toBulgaria, the Czech Republic, Hungary, Poland and Russia.Substantial differences between the adjusted and the observed TFRindicate important tempo effects in the recent decline offertility. Moreover, these five countries differ in the relativeimportance of tempo versus quantum effects, and in the periodwhen tempo effects are most relevant. We discuss the validity ofthe assumptions that underlie the usage of the formula and wetest whether age-period interactions may invalidate theseassumptions.     

Sweeping Changes in Marriage, Cohabitation and Childbearing in Central and Eastern Europe: New Insights from the Developmental Idealism Framework

In Central and Eastern Europe following the political transformations of the late 1980s and early 1990s, there were dramatic declines in marriage and childbearing, significant increases in nonmarital cohabitation and childbearing, and a movement from reliance on abortion to a reliance on contraception for fertility limitation. Although many explanations have been offered for these trends, we offer new explanations based on ideational influences and the intersection of these ideational influences with structural factors. We focus on the political, economic, social, and cultural histories of the region, with particular emphasis on how countries in the region have interacted with and been influenced by Western European and North American countries. Our explanations emphasize the role of developmental models in guiding change in the region, suggesting that developmental idealism influenced family and demographic changes following the political transformations. Developmental idealism provides beliefs that modern family systems help to produce modern political and economic accomplishments, and it helps establish the importance of freedom and equality as human rights in both the public and private spheres. The disintegration of the governments and the fall of the iron curtain in the late 1980s and early 1990s brought new understanding about social, economic, and family circumstances in the West, increasing consumption aspirations and expectations which clashed with both old economic realities and the dramatic declines in economic circumstances. In addition, the dissolution of the former governments removed or weakened systems supporting the bearing and rearing of children; and the legitimacy of the former governments and their programs was largely destroyed, thereby removing government support for old norms and patterns of behavior. In addition, the attacks of previous decades on the religious institutions in the region had in many places left these institutions weak. During this period, many openly reached out to embrace the values, living standards, and economic, political, and familial systems of the West. And, the thirst for freedom—and its considerable expansion—operated in personal and familial as well as political and economic realms. These dramatic changes combined together to produce the many changes occurring in family and demographic behavior.     

Induced Abortion in Russia: Recent Trends and Underreporting in Surveys

The abortion level in Russia has been exceptionally high for several decades, yet during the last ten years it experienced a considerable decline. There is a concern that this favourable change could be largely due to a deterioration of statistical registration in the 1990s. In this paper, we use three reproductive and health surveys for a crosscheck with provider statistics, and analyse patterns and determinants of abortions. Each survey includes questions about the history of abortions. Our data indicate that survey estimates of the crude, total, and age-specific abortion rates emerge to be very close to respective figures from provider statistics for about two years preceding each survey. Survey estimates progressively deviate downwards from provider statistics when moving further back in time due to growing under reporting. This finding suggests that provider statistics on abortion in Russia are a true reflection of the situation they monitor, that the observed declining trend in abortion is a real one, and that analyses of survey data on abortions are justified for up to two years preceding the survey. Logistic regression using the data from the survey carried out in 2000 for the period of 1998-2000 reveals that the odds for an induced abortion are lower in case of a higher educational degree, that the odds increase with the number of children and decrease with the use of more reliable contraceptive methods, and that married women are more likely to have an abortion than never-married ones but less likely when compared to cohabiting women.