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1.
Population Research and Policy Review - Both the industrialization thesis and institutional theories of education hypothesize that early educational expansion increased internal migration. We take...  相似文献   
2.
Objective: Despite declining cigarette smoking rates in the US, there is a continued need for tobacco prevention education campaigns to reach young adults. Recognizing the need for improved tobacco control messaging, the University of Texas (UT) System engaged The University of Texas at Austin Center for Health Communication to develop a brand and message that would strengthen tobacco control efforts at its 14 institutions. Methods: This article describes the iterative process involved in creating a brand for tobacco control, including an environmental scan, identifying potential message themes, and creating and refining logos. Results: This article highlights the process of developing a system-wide tobacco control brand. Specifically, the process included coordinating an interdisciplinary team with content and design experts, and presenting ideas to stakeholders for serial feedback and refinement, among others. Conclusions: Ultimately, this project offers a model for other systems of higher education interested in pursuing similar initiatives.  相似文献   
3.
Robust parameter designs (RPDs) enable the experimenter to discover how to modify the design of the product to minimize the effect due to variation from noise sources. The aim of this article is to show how this amount of work can be reduced under modified central composite design (MCCD). We propose a measure of extended scaled prediction variance (ESPV) for evaluation of RPDs on MCCD. Using these measures, we show that we can check the error or bias associated with estimating the model parameters and suggest the values of α recommended for MCCS under minimum ESPV.  相似文献   
4.
Since Robert Park’s foundational work on the ethnic press, the assimilation-pluralism paradigm has dominated research. This article proposes a new framework that combines ethnic media and diasporic media literatures to advance future scholarship. Ethnic media research can provide direction in better conceptualizing media of ethnic groups/diasporas and can reinforce the importance of racial context, and diasporic media research can address the limitations of the assimilation-pluralism framework and its inability to incorporate globalization, transnationalism, and hybridity. This article submits that ethnic media be conceptualized as specific to media produced by a diasporic or indigenous ethnic population within the host society and that future textual research on ethnic media engage a diasporic identity framework. The framework would (a) call attention to transnationalism; (b) call attention to local/transnational, ethnic/race, and inter-generational tensions; (c) focus on race as a salient and important local context for diasporic meaning; and (d) consider the site of production.  相似文献   
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By treating the 1.5 generation as a distinctive analytic category, this paper compares the effects of generational status on earnings among men of Chinese, Filipinos, and Korean descents in the New York metropolitan area. Our analyses of the 5 percent Public Use Microdata Sample data of the 2000 U.S. census show that all other background characteristics held equal, 1.5‐generation Chinese and Filipino American workers make significantly higher earnings than second‐generation workers. However, Korean American workers do not exhibit this 1.5‐generation advantage. These findings support a segmented assimilation theory, the view that immigrant assimilation paths are not uniform across ethnic groups or generation status. Other findings suggest that bilingual ability would increase earnings only for the Chinese group.  相似文献   
7.
Structural breaks in the level as well as in the volatility have often been exhibited in economic time series. In this paper, we propose new unit root tests when a time series has multiple shifts in its level and the corresponding volatility. The proposed tests are Lagrangian multiplier type tests based on the residual's marginal likelihood which is free from the nuisance mean parameters. The limiting null distributions of the proposed tests are the χ2distributions, and are affected not by the size and the location of breaks but only by the number of breaks.

We set the structural breaks under both the null and the alternative hypotheses to relieve a possible vagueness in interpreting test results in empirical work. The null hypothesis implies a unit root process with level shifts and the alternative connotes a stationary process with level shifts. The Monte Carlo simulation shows that our tests are locally more powerful than the OLSE-based tests, and that the powers of our tests, in a fixed time span, remain stable regardless the number of breaks. In our application, we employ the data which are analyzed by Perron (1990), and some results differ from those of Perron's (1990).  相似文献   

8.
A central issue in principal component analysis (PCA) is that of choosing the appropriate number of principal components to be retained. Bishop (1999a) suggested a Bayesian approach for PCA for determining the effective dimensionality automatically on the basis of the probabilistic latent variable model. This paper extends this approach by using mixture priors, in that the choice dimensionality and estimation of principal components are done simultaneously via MCMC algorithm. Also, the proposed method provides a probabilistic measure of uncertainty on PCA, yielding posterior probabilities of all possible cases of principal components.  相似文献   
9.
The challenge for policy makers and disaster managers is to achieve a balance between two dynamics — resilience and entropy — in order to develop sustainable risk reduction. Achieving an appropriate balance between resilience and entropy in any given community requires a systematic exploration of both dynamics. The recent hurricanes that struck Louisiana, Hurricane Katrina on August 29, 2005 and Hurricane Gustav, on September 1, 2008, offer an unusual opportunity to assess the degree to which both dynamics operated following Hurricane Katrina.  相似文献   
10.
This article addresses the train-sequencing problem encountered in the Korean railway. It first presents a mixed integer programming model for the problem, in which the mileage must be balanced for each train route, while various field constraints must be satisfied, including overnight stay capacity and maintenance allocation restrictions. Then, it proposes a hybrid genetic algorithm as a solution approach to the problem. The proposed algorithm utilizes a modified elite group technique along with two heuristic procedures based on the mixed integer programming model. Finally, the proposed solution approach is tested with real-world data from the Korean railway. Numerical experiments under different conditions indicate that the proposed solution approach to the train-sequencing problem is promising.  相似文献   
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