Analysis of ordered categorical data with score averaging: with applications to case-control genetic associations

The trend test is often used for the analysis of 2×K ordered categorical data, in which K pre-specified increasing scores are used. There have been discussions on how to assign these scores and the impact of the outcomes on different scores. The scores are often assigned based on the data-generating model. When this model is unknown, using the trend test is not robust. We discuss the weighted average of a trend test over all scientifically plausible choices of scores or models. This approach is more computationally efficient than a commonly used robust test MAX when K is large. Our discussion is for any ordered 2×K table, but simulation and applications to real data are focused on case-control genetic association studies. Although there is no single test optimal for all choices of scores, our numerical results show that some score averaging tests can achieve the performance of MAX.     

ANOVA Problems with Simple Numbers

This article shows how to construct simple numerical exercises in balanced and unequally replicated one-way analysis of variance (ANOVA) (and experimental design) such that the estimated effects and residual standard deviations are preassigned whole numbers. Methods for generating single samples and simple linear regressions with exact estimates are already available (see Edwards 1959, Searle and Firey 1980, Posten 1982, and Read and Riley 1983). In this article the basic method of Read and Riley is extended to one-way ANOVA. For small numbers of treatments and replications and small residual standard deviations, tables of basic data are supplied that greatly expedite the construction of ANOVA layouts; the same methods may easily be applied, and the tables extended, to generate exercises involving larger numbers if required. The sets of estimated effects are essentially arbitrary, and so the significance or insignificance of main effects, or of contrasts thereof, can be illustrated by data sets designed for the purpose. This facility is a new and helpful aid to instruction.     

Bartlett-corrected tests for normal linear models when the error covariance matrix is nonscaiar

This paper provides Bartlett corrections to improve likelihood ratio tests for heteroskedastic normal linear models when the error covariance matrix is nonscaiar and depends on a set of unknown parameters. The Bartlett corrections are simple enough to be used algebraically to obtain several closed-form expressions in special cases. The corrections have also advantages for numerical purposes because they involve only simple operations on matrices and vectors.     

Choosing the best population development goal]

Optimizing goals for controlled population growth and development through mathematical modeling has a practical value and is of important theoretical significance. An integrated model for optimizing multiple interactive targets for population development is proposed. A wide array of user-prioritized (weighted) economic indices or factors may be incorporated into this n-tuple m-dimensional model, by which complex linear and vector space computations are solved and interpreted through conventional mathematics. Although this numerical approach toward problem solving is imperfect, when properly used, the mathematical model presented in this paper is a practical and efficient means for solving multidimensional problems.     

Barefoot and in a German kitchen: federal parental leave and benefit policy and the return to work after childbirth in Germany

Since 1979 German federal maternity leave and benefit policy has given women incentives to stay at home and take care of their newborn and youngest children. In 1986 this leave and benefit policy was changed in several ways, turning it into a powerful instrument for delaying mothers' return to work after childbirth. Using a flexible duration dependence estimation technique for proportional hazards due to Prentice and Gloeckler (1978) and applied to grouped durations by Meyer (1987, 1990), we estimate post childbirth return to work hazards for women during the federally protected leave protection period and immediately upon completion of this leave period. During the leave mothers are less likely to return to work the longer is the time left in the leave protection period; however, this result cannot be attributed generally to high levels of maternity benefits. When the leave protection period ends, mothers with strong labor force attachment who are still on leave return to their jobs.The second author gratefully acknowledges financial support by the National German Science Foundation (Deutsche Forschungsgemeinschaft) (Grant No. Wa 547/2-1). The authors would like to thank Richard Burkhauser, Barbara Butrica, John F. Ermisch, Joachim Frick, Siv Gustafsson, Philip Merrigan, Johannes Schwarze, Eileen Trzcinski, Jan-Dirk Vlasblom, Gert Wagner, Sheng Zhu and two anonymous referees for their help and suggestions. Remaining errors are of course, our own. Responsible editors: Siv S. Gustafsson, John F. Ermisch.     

Shift the focus of family-planning work to one couple giving birth to one child--an investigative report on family-planning conditions in Shifang County]

Sheng-Fang county of Sichuan province, China, is famous for its successful birth control program. The rate of natural increase declined from 32% in 1970 to 2.6% in 1979 with a 99.3% rate of planned birth. Each couple averaged only 2 children in 1978 but, with population increasing faster than the food supply, there was still room for improvement. In order to reach the goal of a 5% rate of natural increase in 1985 and a 0% rate in the year 2000, it was necessary to advocate "one couple one child". With 90% of the families complying with this rule, the goal could nearly be met. Instilling this norm in a rural area where childbearing has traditionally been valued, especially for old age security, required careful educating of the population. A campaign was conducted to inform the people of the benefits to the country, the community, and themselves of smaller families. Incentive programs reinforced the lessons. The Party leaders considered instillation of the 1-child/family norm a top priority and worked to put it into effect. The educational work must continue, to reach newly married couples and to maintain the resolve of couples reached earlier. Child health programs were improved as well as old age security programs to obviate the need for extra children.     

Explaining immigrant naturalization

"Prior research on immigrant naturalization has focused mainly on the effects of immigrants' adaptation experiences and demographic characteristics on their propensity to naturalize. This article proposes a broader analytical framework which incorporates immigrants' individual characteristics and larger social contexts in the country of origin and the country of destination to explain the likelihood of citizenship acquisition. The framework is tested for a cohort of recent immigrants, using the PUMS data from the 1980 U.S. census. The results show that economic, political, social, cultural and geographical conditions in the country of origin, and immigrants ethnic communities and urban concentration in the country of destination, to a large extent influence immigrants' propensity for naturalization and that, net of the contextual factors, many of the immigrants' adaptation and demographic characteristics are also significant predictors of citizenship acquisition."     

On prediction from the location-scale model with a compound error distribution

The prediction distribution of future response(s) given a set of data from a location-scale model with a compound error distribution has been derived by utilizing the structural relations of the model. The compound error distribution has been specialized to cover the case of multivariate t-distribution.     

Unmet Home Care Service Needs of Rural Older Adults With Alzheimer's Disease: A Perspective of Informal Caregivers

This study assessed unmet service needs of rural older adults with Alzheimer's disease (AD) and identified factors that were related to these needs. Data were collected from 109 informal caregivers of AD patients. Over half of the patients experienced unmet service needs in 1 or more areas of activities of daily functioning. Informal caregiver burden and patient's gender and functional status were significantly related to patients' unmet service needs. Patients' use of formal services was marginally related to their unmet service needs. To better address patients' service needs, a comprehensive needs assessment should be conducted with both patients and their caregivers.