Post-1969 Immigration and the Example of the Insolvency of the Social Security System

Advocates of immigration to save Social Security (S.S.) assume that a pay-as-you-go system will work over the long run. That assumption is not shared by the Social Security Board of Trustees. Reflection shows that it would entail ever-larger new cohorts of immigrants to support those who are retiring, in effect, a Ponzi scheme. In fact, the benefits structure of the S.S. system, which pays out proportionately more to low-wage earners than to high-wage earners relative to their contributions, taken together with the income profile of post-1969 immigrants, means that the more immigration which occurs, the deeper into insolvency the system falls.     

Contraception,attitude-practice,and fertility differentials among US Hispanic,African–American and white women

Hispanic fertility (primarily among nationals from Mexico, Central and South America in the US) is higher today than it is in Mexico and the other nations of origin (Frank and Heuveline 2005). It persists into the second and third generations, with only moderate signs of declining to replacement. Meanwhile, the fertility rates of African–Americans, American Indians Cubans, and Puerto Ricans have all declined to replacement, only slightly above the non-Hispanic white population. This study attempts to clarify the question why African–American fertility has declined to replacement, but Hispanic fertility has not. The data used are from Cycle 6 of the National Survey of Family Growth (NSFG) of 2002. Differences in physiological or marital-status factors are found not to explain these fertility differences; however, there are significant differences in the practice of contraception during early childbearing years. Slightly less effective methods if contraception is used, and less recourse to abortion if a pregnancy is undesired, all imply higher fertility for Hispanic women. Underlying contraceptive behaviour are sets of attitudes and motives that favour, permit, or seek childbearing. A much higher percentage of Hispanic than African–American women report that they wanted their last birth and intend to have another in the future. Hispanic women of all socio-economic statuses are considerably more pronatal in their attitudes, particularly with respect to the births of first and second children.     

Perceptions of Sexual Consent: The Impact of Relationship History and Gender

Patterns of extradyadic involvement (EDI) were assessed for 3 samples: an undergraduate dating sample and a community marital sample reporting on an actual experience of EDI, and an undergraduate sample which denied recent EDI and was asked to imagine a hypothetical EDI experience. Good consistency of responses within and between measures was found for the hypothetical EDI sample. Persons reporting on a hypothetical EDI were generally less approving of EDI and imagined that they would experience higher levels of primary relationship satisfaction, overall remorse, and specific types of distress, particularly in comparison to the dating EDI group. Relative to the dating EDI group, the marital EDI group recalled greater dissonance with the EDI behavior, more concern about disapproval from others, and higher levels of intimacy, self‐esteem, and love reasons for the EDI. No differences were found among the groups on the level of emotional closeness with the extradyadic partner.     

An examination of population changes in Alabama's black belt counties: 1960–1970 and 1970–1980

Population changes in 11 Alabama Black Belt counties are examined by comparing annual average birth, death, and migration rates during the 1960s with those of the 1970s. The specific focus of the study is migration patterns among the nonwhite segment of the population. Data from the 1980 and earlier censuses are utilized, along with birth and death data from Alabama vital statistics reports. Average annual migration rates for each of the two decades are derived. The results indicate that net migration losses among nonwhites declined substantially during the 1970s compared with the 1960s and that in two Black. Belt counties there was a reversal from heavy net losses to moderate net gains. Whites, on a county‐to‐county basis, however, were generally characterized by significantly higher rates of loss during the 1970s than in the 1960s. The substantial reduction in outmigration rates among nonwhites is tentatively attributed to political and economic advances coupled with increased employment opportunities in nonagricultural occupations.     

Computation of the Generalized F Distribution

Exact expressions for the cumulative distribution function of a random variable of the form ( α ₁ X ₁+ α ₂ X ₂)/ Y are given where X ₁, X ₂ and Y are independent chi-squared random variables. The expressions are applied to the detection of joint outliers and Hotelling's mis-specified T ² distribution.     

Influence functions applied to the estimation of mean rain rate

In this paper we illustrate the usefulness of influence functions for studying properties of various statistical estimators of mean rain rate using space-borne radar data. In Martin (1999), estimators using censoring, minimum chi-square, and least squares are compared in terms of asymptotic variance. Here, we use influence functions to consider robustness properties of the same estimators. We also obtain formulas for the asymptotic variance of the estimators using influence functions, and thus show that they may also be used for studying relative efficiency. The least squares estimator, although less efficient, is shown to be more robust in the sense that it has the smallest gross-error sensitivity. In some cases, influence functions associated with the estimators reveal counterintuitive behaviour. For example, observations that are less than the mean rain rate may increase the estimated mean. The additional information gleaned from influence functions may be used to understand better and improve the estimation procedures themselves.     

Moments of order statistics from a non-overlapping mixture model with applications to truncated laplace distribution

We employ two different approaches to derive single and product moments of order statistics from a truncated Laplace distribution. A direct evaluation method establishes recurrence relations whereas the more general non-overlapping mixture model incorporates the truncated Laplace distribution as a special case. The results are thereafter applied to estimate location and scale parameters of such distributions.     

Sequential analysis of 3m supersaturated factorial experiments

In this paper, designs that allow for the estimation of all main effects, and the detection and estimation of significant interactions in fewer runs than used in traditional approaches are examined. Specifically, a method for sequentially analyzing data from 3m fractional factorial experiments is presented. The procedure is illustrated through two examples.