Cohort parity analysis: Statistical estimates of the extent of fertility control

Cohort parity analysis (CPA) is a method for indirect measurement of the extent and timing of the adoption of fertility control within marriage. It uses information on the parity distribution of a cohort of women of specified marriage ages and durations. A multinomial model of parity provides a convenient framework for the computation of distributional parameters describing the extent to which marital fertility control has been accepted and characterizing the way control has been used within specific durations of marriage. This leads to a pair of easily implemented formulas for upper- and lower-bound estimates of the expected proportion of the population ever controlling and the distribution of controllers by parity. The power of CPA is illustrated, using census data for currently married couples in Dublin, Belfast, and other county boroughs of Ireland in 1911.     

A model of the determinants in married women of sterilization method choice

A model for predicting sterilization method selection is constructed on the basis of hypotheses about 1. the relationship between the fertility termination, sterilization, and method selection decisions and 2. the influence of substantive, processual, and contextual factors in those decisions. The model is found to have an acceptably good fit to data from almost five hundred women in married couples selecting either tubal ligation or vasectomy. A number of interesting dynamic pathways leading to method selection are observed. Some weaknesses in the model are discussed. It is desirable that further confirmation and elaboration of the model using longitudinal and husband-wife data be undertaken.This paper is based on a study funded by the National Institutes of Child Health and Human Development, Center for Population Research, Grant Number 13459.     

Polygyny and Fertility among the Shipibo of the Peruvian Amazon

This report describes a study of the fertility experience of an Amazon Indian tribe that has shown evidence of having the highest documented fertility of any human group. The Shipibo, who live in the upper Peruvian Amazon, are experiencing rapid cultural change, including a decline in the prevalence of polygyny. This study tests the specific hypotheses that polygyny limits individual female and community fertility through the mechanism of post partum sexual abstinence and longer birth intervals. Total population counts in eight villages and reproductive histories of all females age 13+ show that mean birth interval lengths of polygynous women are four months longer than those of monogamous women. Fertility of polygynous women was lower, with 1.3 fewer term-births per reproductive span than that of monogamous women. The community general fertility rate is negatively associated with the proportion of polygynous birth intervals in the community. In this study, cultural change is strongly associated with higher fertility.     

Properties of simultaneous confidence intervals for multinomial proportions

Inversion of Pearson's chi-square statistic yields a confidence ellipsoid that can be used for simultaneous inference concerning multinomial proportions. Because the ellipsoid is difficult to interpret, methods of simultaneous confidence interval construction have been proposed by Quesenberry and hurst,goodman,fitzpatrick and scott and sison and glaz . Based on simulation results, we discuss the performance of these methods in terms of empirical coverage probabilities and enclosed volume. None of the methods is uniformly better than all others, but the Goodman intervals control the empirical coverage probability with smaller volume than other methods when the sample size supports the large sample theory. If the expected cell counts are small and nearly equal across cells, we recommend the sison and glaz intervals.     

Student assistance program: a new approach for student success in addressing behavioral health and life events

College health centers, whether large or small, often find it challenging to provide counseling and supportive services for all students (including remotely located students) 24 hours a day, 7 days a week. Student assistance programs (SAPs) are services provided to students through a contractual arrangement to the university or college as a part of student services. The goal is to address psychosocial concerns that may interfere with academic performance within the realm of short-term counseling. These services range from traditional behavioral health concerns about stress and depressive reactions to how to find child care with foreign-speaking services. In this article, the authors describe a method to provide such short-term counseling to a 2,200-student health-science campus. They present data from 1 year of service as well as the benefits and limitations.     

A Note on Consistency in Utility Assessment*

A methodology for determining a von Neumann-Morgenstern utility function is outlined based on the axioms crucial to such a function. Reconciliation of inconsistent judgments is facilitated using the theory of reciprocal matrices. Numerical measures of the collective divergence of a set of judgments from perfect consistency or coherency are provided.     

ESTIMATING WAITING TIME IN A QUEUING SYSTEM*

This study examines how customers joining a queuing system assess their waiting time in the system. Data obtained from an actual queuing system support the paradigm of Parkan and Warren [5] on the use of the observed number in the system in this assessment. It is concluded that customers overestimate mean service time but that this overestimation is not dependent on the number in the system.