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131.
This paper uses data from the Fragile Families and Child Wellbeing Study to test the hypotheses that (1) similar to other
positive pre- and post-natal outcomes, Mexican immigrant mothers are more likely to breastfeed, and to breastfeed longer,
than white or Mexican-American mothers; and (2) acculturation accounts for the ethnic/nativity differential in breastfeeding
initiation and duration. The results support both hypotheses. Mexican immigrants to the U.S. are much more likely than whites
to breastfeed, and to breastfeed longer. Mexican-American mothers, after controlling for background characteristics, have
similar initiation and duration to whites. Using expanded acculturation measures developed for this paper, acculturation accounts
for some of the difference between whites and Mexican immigrants in breastfeeding initiation, and much of the difference for
breastfeeding duration. The results suggest that low levels of acculturation operate to protect Mexican immigrants from choosing
to formula-feed, which gives their babies many health advantages, and may be associated with better health outcomes across
the life course. The results also suggest that successive generations of Mexican immigrants may abandon breastfeeding, which
is deleterious for their infants. 相似文献
132.
Ann Morning 《Population research and policy review》2008,27(2):239-272
Academic interest in official systems of racial and ethnic classification has grown in recent years, but most research on
such census categories has been limited to small case studies or regional surveys. In contrast, this article analyzes a uniquely
global data set compiled by the United Nations Statistical Division to survey the approaches to ethnic enumeration taken in
141 countries. The motives for this analysis combine theoretical, applied, and policy objectives. I find that 63% of the national
censuses studied incorporate some form of ethnic enumeration, but their question and answer formats vary along several dimensions
that betray diverse conceptualizations of ethnicity (for example, as “race” or “nationality”). Moreover, these formats follow
notably regional patterns. Nonetheless, the variety of approaches can be grouped into a basic taxonomy of ethnic classification
approaches, suggesting greater commonality in worldwide manifestations of the ethnicity concept than some have recognized.
相似文献
Ann MorningEmail: |
133.
Myron P. Gutmann Kristine Witkowski Corey Colyer JoAnne McFarland O’Rourke James McNally 《Population research and policy review》2008,27(6):639-665
Spatially explicit data pose a series of opportunities and challenges for all the actors involved in providing data for long-term
preservation and secondary analysis—the data producer, the data archive, and the data user. We report on opportunities and
challenges for each of the three players, and then turn to a summary of current thinking about how best to prepare, archive,
disseminate, and make use of social science data that have spatially explicit identification. The core issue that runs through
the paper is the risk of the disclosure of the identity of respondents. If we know where they live, where they work, or where
they own property, it is possible to find out who they are. Those involved in collecting, archiving, and using data need to
be aware of the risks of disclosure and become familiar with best practices to avoid disclosures that will be harmful to respondents.
相似文献
Myron P. GutmannEmail: |
134.
M-quantile models with application to poverty mapping 总被引:1,自引:0,他引:1
Nikos Tzavidis Nicola Salvati Monica Pratesi Ray Chambers 《Statistical Methods and Applications》2008,17(3):393-411
Over the last decade there has been growing demand for estimates of population characteristics at small area level. Unfortunately,
cost constraints in the design of sample surveys lead to small sample sizes within these areas and as a result direct estimation,
using only the survey data, is inappropriate since it yields estimates with unacceptable levels of precision. Small area models
are designed to tackle the small sample size problem. The most popular class of models for small area estimation is random
effects models that include random area effects to account for between area variations. However, such models also depend on
strong distributional assumptions, require a formal specification of the random part of the model and do not easily allow
for outlier robust inference. An alternative approach to small area estimation that is based on the use of M-quantile models
was recently proposed by Chambers and Tzavidis (Biometrika 93(2):255–268, 2006) and Tzavidis and Chambers (Robust prediction
of small area means and distributions. Working paper, 2007). Unlike traditional random effects models, M-quantile models do
not depend on strong distributional assumption and automatically provide outlier robust inference. In this paper we illustrate
for the first time how M-quantile models can be practically employed for deriving small area estimates of poverty and inequality.
The methodology we propose improves the traditional poverty mapping methods in the following ways: (a) it enables the estimation
of the distribution function of the study variable within the small area of interest both under an M-quantile and a random
effects model, (b) it provides analytical, instead of empirical, estimation of the mean squared error of the M-quantile small
area mean estimates and (c) it employs a robust to outliers estimation method. The methodology is applied to data from the
2002 Living Standards Measurement Survey (LSMS) in Albania for estimating (a) district level estimates of the incidence of
poverty in Albania, (b) district level inequality measures and (c) the distribution function of household per-capita consumption
expenditure in each district. Small area estimates of poverty and inequality show that the poorest Albanian districts are
in the mountainous regions (north and north east) with the wealthiest districts, which are also linked with high levels of
inequality, in the coastal (south west) and southern part of country. We discuss the practical advantages of our methodology
and note the consistency of our results with results from previous studies. We further demonstrate the usefulness of the M-quantile
estimation framework through design-based simulations based on two realistic survey data sets containing small area information
and show that the M-quantile approach may be preferable when the aim is to estimate the small area distribution function. 相似文献
135.
136.
Sourour Elloumi 《Journal of Combinatorial Optimization》2010,19(1):69-83
Given a set of clients and a set of potential sites for facilities, the p-median problem consists of opening a set of p sites and assigning each client to the closest open facility to it. It can be viewed as a variation of the uncapacitated
facility location problem. We propose a new formulation of this problem by a mixed integer linear problem. We show that this
formulation, while it has the same value by LP-relaxation, can be much more efficient than two previous formulations. The
computational experiment performed on two sets of benchmark instances has showed that the efficiency of the standard branch-and-cut
algorithm has been significantly improved. Finally, we explore the structure of the new formulation in order to derive reduction
rules and to accelerate the LP-relaxation resolution. 相似文献
137.
138.
139.
Sheretta T. Butler-Barnes Stephanie Cook Seanna Leath Cleopatra Caldwell 《Race and social problems》2018,10(1):30-41
This study explored the extent to which private regard and religiosity beliefs serve as protective factors for school bonding among African American and Caribbean black adolescents who experience racial discrimination in school. Findings are drawn from a nationally representative sample of (n = 810) African American and (n = 360) Caribbean black adolescents (52% girls) aged 13–17 (Mage = 15, SD = 1.42) years. Results suggest that perceiving racial discrimination from teachers was associated with lower levels of school bonding for African American and Caribbean black adolescents. For African American adolescents, perceiving more racial discrimination from teachers and reporting lower private regard beliefs was associated with less school bonding. The findings for Caribbean black adolescents revealed that endorsing moderate levels of religiosity and perceiving higher rates of teacher discrimination was associated with less school bonding. The developmental significance and implications for future research are discussed. 相似文献
140.
In this paper, we analyze the ethical issues of using honesty and integrity tests in employment screening. Our focus will be on the United States context: legal requirements related to applicant privacy differ in other countries, but we posit that our proposed balancing test is broadly applicable. We start by discussing why companies have ethical and legal obligations, based on a stakeholder analysis, to assess the integrity of potential employees. We then move to a consideration of how companies currently use background checks as a pre‐employment screening tool, noting their limitations. We then take up honesty and integrity testing, focusing particularly on the problems of false positives and due process. We offer a balancing test for the use of honesty and integrity testing that takes in three factors: (1) the potential harm posed by a dishonest employee in a particular job, (2) the linkage between the test and the assessment process, and (3) the accuracy and validity of the honesty and integrity test. We conclude with implications for practice and future research. 相似文献