The Effects of the Registration System on the Seasonality of Births: The Case of the Soviet Union

Scientists study seasonality in order to understand the effect of environmental, biological, and social factors on demographic events. Poor data quality can also affect seasonal variation in mortality and fertility statistics. The influence of error on seasonal data becomes crucial as researchers analyze timing and spacing of events in time-series analyses. In this study we examine the reported number of births by month in the Soviet Union for 1950, 1955, and 1958–85. The lowest number of births has typically occurred in December, and the highest in January. This seasonal pattern is not consistent with any plausible biological or behavioural explanation. It is probably an artifact of attributing births that actually occurred during the preceding December or earlier, to January. This implies that Soviet statistical practice has not followed the stated policy of attributing births to the period (day, month, year) in which they occur. A substantial reduction between the 1950s and 1985 in the December-January peak in reported births implies marked improvement in Soviet vital registration statistics. The Soviet case shows that characteristics of the registration system can impart a particular seasonal pattern to demographic data. It also shows that officially prescribed procedures are not always followed in data generation, even in centrally planned economies. Researchers should carefully examine the quality of seasonal data before concluding that the data reflect real variations in demographic behaviour.     

Pragmatics of Self- and Other-Reference in Young Children

During the first years of life, children come to understand and talk about a self separate from others. This study examined self- and other-reference and communicative intents expressed by children and parents in dyadic interaction at 14, 20 and 32 months. Research questions included whether children's early use of self- and other-reference pronouns occurred for expression of particular communicative intents, how use changed with age, and whether parent and child pragmatic expressions of self and other were similar. Results showed that children's early explicit reference to self tended to take the form of I rather than me/my/mine, and was used primarily in making statements about their intended actions, in making requests or proposals to their parents and in stating propositions about the world around them. Children during this developmental period were only beginning to refer to the present other with the pronoun you and these instances occurred primarily in making requests or proposals. Despite age-related increases in pronominal forms and intents, a small set of intents continued to provide the context for most self- and other-reference pronouns. In the communicative contexts in which they explicitly refer to self and other, children did not appear to exclusively mirror those which were observed in parental speech.     

Commentary on “Economic Preferences or Attitude Expressions?: An Analysis of Dollar Responses to Public Issues” by Kahneman,Ritov and Schkade

Journal of Risk and Uncertainty -     

Out-of-Sample Forecast Tests Robust to the Choice of Window Size

This article proposes new methodologies for evaluating economic models’ out-of-sample forecasting performance that are robust to the choice of the estimation window size. The methodologies involve evaluating the predictive ability of forecasting models over a wide range of window sizes. The study shows that the tests proposed in the literature may lack the power to detect predictive ability and might be subject to data snooping across different window sizes if used repeatedly. An empirical application shows the usefulness of the methodologies for evaluating exchange rate models’ forecasting ability.     

Keeping a Home: Changing Mortgage Markets and Regional Economic Distress

Abstract

In the relatively affluent post World War II period, homeownership in the United States has risen steadily to include an increasing segment of the working class. Although the extension of homeownership has helped to attenuate some of the inequalities of class and to integrate the more affluent segments of the working class into the social and political mainstream, economic and political events are threatening this historic trend. Dependent upon long term financing, homeownership has two components: keeping as well as buying a home. High and persistent rates of unemployment in old industrial areas have meant the loss of stable incomes for skilled workers, and with it, rising rates of home mortgage delinquency and foreclosure. To examine the threat to continued homeownership, this paper locates homeownership in its structural context, at the intersection of major changes in financial institutions (deregulation) as well as local economic and industrial change.

Our research suggests that regional economic difficulties are being exaccerbated by national deregulatory trends. We found that deregulation has facilitated a general movement from a local to a nonlocal mortgage market. This includes the growth and privatization of the secondary mortgage market and the repositioning of lenders in the local market. We found that delinquent homeowners with locally held and serviced mortgages were better able to negotiate forebearance with their lenders for reasons ranging from the ability to exert public pressure to the economic self-interest of local lenders. Except for FHA mortgages, delinquent homeowners with nonlocal mortgages were penalized. For blue collar workers, the loss of a home more than the loss of a job removes an important class buffer thus reversing a post World War II trend.     

Formative research methods to understand patient and provider responses to heart attack symptoms

Formative research is often required for program planning, and for reducing uncertainty about generalizability of program effects. This article describes and justifies methods of formative research conducted for the REACT study (Rapid Early Action for Coronary Treatment), a multi-center collaborative randomized community trial aimed at reducing patient delay in seeking care for acute myocardial infarction (AMI). Formative research cast light on patient and community members’ decision-making process in seeking help for AMI, as well as barriers and facilitators of this process. Investigators at all five REACT Field Centers participated in the formative research. The process consisted of: (1) developing a common theoretical framework for the study intervention; (2) conducting a literature review and qualitative research to identify and address gaps in knowledge; and (3) developing a common protocol for the REACT study that accommodated the diversity of the target communities in terms of services, resources, history, and ethnicity. Analysis employed triangulation, defined as an explicit search for heterogeneous data sources to reduce uncertainty about forces at work and opportunities for intervention across settings and populations. Because the collection and interpretation of data went in stages, staff of several REACT Field Centers had independent input to the overall synthesis, then shared and revised the results. Advantages and limitations of this approach are discussed.     

T-optimum designs for discrimination between two multiresponse dynamic models

Summary.  The paper is concerned with a problem of finding an optimum experimental design for discriminating between two rival multiresponse models. The criterion of optimality that we use is based on the sum of squares of deviations between the models and picks up the design points for which the divergence is maximum. An important part of our criterion is an additional vector of experimental conditions, which may affect the design. We give the necessary conditions for the design and the additional parameters of the experiment to be optimum, we present the algorithm for the numerical optimization procedure and we show the relevance of these methods to dynamic systems, especially to chemical kinetic models.