A demonstration of the effect of seasonal migration on fertility

Fertility estimates were calculated using own children data from the Mexican migrant town of Guadalupe, Michoacan. In this town, 75 percent of families have a member working in the United States, and wives are often regularly separated from their migrant husbands. Simulations by Menken (1979) and Bongaarts and Potter (1979) suggest that fertility among these women should be depressed. Our results confirmed this hypothesis, showing that the seasonal absence of migrant husbands disrupted both the level and timing of fertility. However, the effect was greater for legal than for illegal migrants, a pattern that stemmed from social factors as well as physical separation. A logistic regression analysis showed that reductions in birth probabilities are greater the longer a couple is separated, and that these reductions are in the range expected from prior simulations.     

Research misconduct and crime lessons from criminal science on preventing misconduct and promoting integrity

For 200 years, criminologists theorized that delinquent and criminal acts arise from deviant psychological states (such as irrationality or immorality) and/or social conditions that produce these psychological states. This theoretical perspective, which is being duplicated in most efforts to understand and control research misconduct, has not been productive. More recently, criminological perspectives have emerged, emphasizing situational factors that enhance or restrict the opportunity for illegal or imprudent behavior. These so-called "opportunity" theories have been shown to have practical value in reducing crime rates. We explore the promise of these newer theories for the responsible conduct of research (RCR).     

Alcohol abuse on a college campus: A needs assessment

This paper reports the results of a needs assessment study conducted by a university-based alcohol abuse prevention project. Data are presented on the drinking patterns and drinking problems of a random sample of 462 students. Results suggest that students are experiencing numerous difficulties in the physical, educational, legal and psychosocial areas due to their use of alcoholic beverages. Implications for prevention and intervention programming are discussed and the need for planning programs from a data-based perspective rather than a rational and intuitive approach is stressed.     

The Distribution of Sums of Rounded Percentages

When percentages are computed for counts in several categories or for several positive measurements0 each taken as a fraction of their sum, the rounded percentages often fail to add to 100 percent. We investigate how frequently this failure occurs and what the distributions of sums of rounded percentages are for (1) an empirical set of data, (2) the multinomial distribution in small samples, (3) spacings between points dropped on an interval-the broken-stick model-; and (4) for simulation for several categories. The several methods produce similar distributions.We find that the probability that the sum of rounded percentages adds to exactly 100 percent is certain for two categories, about three-fourths for three categories, about two-thirds for four categories, and about [Formula: see text] for larger numbers of categories, c, on the average when categories are not improbable.     

Valuing housework time from willingness to spend time and money for environmental quality improvements

We develop a new approach to assessing the value of home production time based on willingness to spend time and money to obtain environmental improvements. When peoples’ choice is constrained by time as well as money, measures of willingness to pay can be defined with respect to either numeraire. In a model that explicitly allows for multiple shadow values of time, we show that the willingness to pay time and money measures are linked through the value of saving time. With survey information on peoples’ willingness to spend additional time on housework activities, as well as pay money, to obtain environmental quality improvements, joint estimation within a utility-consistent structure produces estimates of both willingness to pay and the value of saving housework time. From the value of saving housework time, the marginal value of housework time can be readily identified. When applied to Korean households’ valuation of water quality improvements in the Man Kyoung River, we find that the value of housework time is 70–80% of the market wage.

Fitting In: Segregation, Social Class, and the Experiences of Black Students at Selective Colleges and Universities

We analyzed qualitative data gathered at a selective urban university with a large black student body. We found that black students from integrated backgrounds welcomed the chance to establish friendships with same-race peers even though they were at ease in white settings, whereas students from segregated backgrounds saw same-race peers as a source of comfort and refuge from a white world often perceived as hostile. These contrasting perceptions set up both groups for shock upon matriculation. Students from an integrated background were better prepared academically and socially, but were unfamiliar with urban black culture and uncomfortable interacting with students of lower class standing. Students from a segregated background were surprised to find they had little in common with more affluent students from integrated backgrounds. Although both groups were attracted to campus for the same reason??to interact with a critical mass of same-race peers??their contrasting expectations produced a letdown as the realities of intraracial diversity set in.     

Origins of the New Latino Underclass

Over the past four decades, the Latino population of the United States was transformed from a small, ethnically segmented population of Mexicans in the southwest, Puerto Ricans in New York, and Cubans in Miami into a large national population dominated by Mexicans, Central Americans, and South Americans. This transformation occurred through mass immigration, much of it undocumented, to the point where large fractions of non-Caribbean Hispanics lack legal protections and rights in the United States. Rising illegality is critical to understanding the disadvantaged status of Latinos today. The unauthorized population began to grow after avenues for legal entry were curtailed in 1965. The consequent rise in undocumented migration enabled political and bureaucratic entrepreneurs to frame Latino migration as a grave threat to the nation, leading to a rising frequency of negative framings in the media, a growing conservative reaction, and increasingly restrictive immigration and border policies that generated more apprehensions. Rising apprehensions, in turn, further enflamed the conservative reaction to produce even harsher enforcement and more still more apprehensions, yielding a self-feeding cycle in which apprehensions kept rising even though undocumented inflows had stabilized. The consequent militarization of the border had the perverse effect of reducing rates of out-migration rather than inhibiting in-migration, leading to a sharp rise in net undocumented population and rapid growth of the undocumented population. As a result, a majority of Mexican, Central American, and South American immigrants are presently undocumented at a time when unauthorized migrants are subject to increasing sanctions from authorities and the public, yielding downward pressure on the status and well-being of Latinos in the United States.     

Using the singly truncated normal distribution to analyze satellite data

This paper proposes the singly truncated normal distribution as a model for estimating radiance measurements from satellite-borne infrared sensors. These measurements are made in order to estimate sea surface temperatures which can be related to radiances. Maximum likelihood estimation is used to provide estimates for the unknown parameters. In particular, a procedure is described for estimating clear radiances in the presence of clouds and the Kolmogorov-Smirnov statistic is used to test goodness-of-fit of the measurements to the singly truncated normal distribution. Tables of quantile values of the Kolmogorov-Smirnov statistic for several values of the truncation point are generated from Monie Carlo experiment Mnally a numerical emample using satetic data is presented to illustrate the application of the procedures.     

Money-Demand Variability: A Demand-Systems Approach

This article tests the Fourier flexible form on quarterly U.S. monetary data. The data have been prescreened for consistency with the general axiom of revealed preference, and subindexes are formed using the Divisia approach. In this article, the global Fourier model fits well, although there is a potential problem of overfitting and certain data points exhibit behavior inconsistent with the model. The elasticities are variable over time, particularly around business-cycle troughs. It appears that financial asset demand surfaces are highly nonlinear and the many unsuccessful existing attempts to estimate money demand may not have worked well for this reason.