American public opinion toward Japan grew more negative coincident with 1980s "Japan-bashing" media messages. Two theories of opinion formation provide explanations for this. Democratic representation theory understands opinions as rational responses to new information. Cultural interpretation theory holds that public opinion is based on one's receptiveness to media discourse. Opinion is neither a rational response to information nor the passive acceptance of elite dictates. People differentially interpret media messages and form opinions in a process that is shaped by media attentiveness and their subjective cultural anxieties. Survey data permit an indirect test of the two theories applied to anti-Japan opinion. OLS regression analysis performed on GSS for four time periods reveals that anti-Japan opinion is rooted less in "rational" responses to personal economic insecurity or fear of increased global competition than in racial attitudes and domestic social-cultural concerns. America's negative opinion toward Japan in the 1990s is better understood as domestic anxieties that are redirected toward a symbolic target that the mass media has highlighted. 相似文献
Model selection strategies play an important, if not explicit, role in quantitative research. The inferential properties of these strategies are largely unknown, therefore, there is little basis for recommending (or avoiding) any particular set of strategies. In this paper, we evaluate several commonly used model selection procedures [Bayesian information criterion (BIC), adjusted R2, Mallows’ Cp, Akaike information criteria (AIC), AICc, and stepwise regression] using Monte-Carlo simulation of model selection when the true data generating processes (DGP) are known.
We find that the ability of these selection procedures to include important variables and exclude irrelevant variables increases with the size of the sample and decreases with the amount of noise in the model. None of the model selection procedures do well in small samples, even when the true DGP is largely deterministic; thus, data mining in small samples should be avoided entirely. Instead, the implicit uncertainty in model specification should be explicitly discussed. In large samples, BIC is better than the other procedures at correctly identifying most of the generating processes we simulated, and stepwise does almost as well. In the absence of strong theory, both BIC and stepwise appear to be reasonable model selection strategies in large samples. Under the conditions simulated, adjusted R2, Mallows’ Cp AIC, and AICc are clearly inferior and should be avoided. 相似文献
We consider a continuous‐review inventory problem for a retailer who faces random disruptions both internally and externally (from its supplier). We formulate the expected inventory cost at this retailer and analyze the properties of the cost function. In particular, we show that the cost function is quasi‐convex and therefore can be efficiently optimized to numerically find the optimal order size from the retailer to the supplier. Computational experiments provide additional insight into the problem. In addition, we introduce an effective approximation of the cost function. Our approximation can be solved in closed form, which is useful when the model is embedded into more complicated supply chain design or management models. 相似文献
Many statistical agencies, survey organizations, and research centers collect data that suffer from item nonresponse and erroneous or inconsistent values. These data may be required to satisfy linear constraints, for example, bounds on individual variables and inequalities for ratios or sums of variables. Often these constraints are designed to identify faulty values, which then are blanked and imputed. The data also may exhibit complex distributional features, including nonlinear relationships and highly nonnormal distributions. We present a fully Bayesian, joint model for modeling or imputing data with missing/blanked values under linear constraints that (i) automatically incorporates the constraints in inferences and imputations, and (ii) uses a flexible Dirichlet process mixture of multivariate normal distributions to reflect complex distributional features. Our strategy for estimation is to augment the observed data with draws from a hypothetical population in which the constraints are not present, thereby taking advantage of computationally expedient methods for fitting mixture models. Missing/blanked items are sampled from their posterior distribution using the Hit-and-Run sampler, which guarantees that all imputations satisfy the constraints. We illustrate the approach using manufacturing data from Colombia, examining the potential to preserve joint distributions and a regression from the plant productivity literature. Supplementary materials for this article are available online. 相似文献
The authors explored relationships among childhood abuse, suicidal ideation, and sexual orientation of 18- to 30-year-old students enrolled in 2 San Diego area colleges, using responses from anonymous questionnaires. Sixty percent of the 138 eligible respondents were women, and 22% were self-identified gay/bisexual individuals. Women were more likely than men to report at least 1 form of emotional abuse (odds ratio [OR] = 2.3; p =.02) and unwanted sexual touching (OR = 4.3; p = .0004). Lesbian/bisexual women were significantly more likely to report past suicidal ideation than were heterosexual women (OR = 3.7, p = .03). Gay/bisexual men were more likely to report unwanted sexual touching than were heterosexual men (OR = 5.1, p = .04), but the men did not report significantly higher rates of past suicide ideation or suicide attempts. Sexual orientation and a past history of child sexual, physical, and emotional abuse could be compounding risk factors for suicidal ideation among college students. 相似文献
We review conceptual issues and theoretical frameworks related to users' acceptability of new technologies designed to protect reproductive health and prevent unwanted pregnancy. Special attention is given to distinctions among different kinds of users' perspectives regarding acceptability, as well as differentiating acceptability from assessments of the efficacy of innovative methods. Emphasis is also given to the larger context of couple decision-making and cultural variation. We argue that concern for sexual pleasure plays a central role in determining user perspectives regarding new methods. The female condom, contraceptive ring, contraceptive skin patch, microbicides, vaccines, emergency contraception, and PERSONA are discussed within the context of the identified critical issues . 相似文献
In “Crime and Juvenile Delinquency,” Lawrence W. Sherman, a professor at the University of Pennsylvania’s Department of Sociology,
describes how changes in criminal and other dysfunctional behaviors could be measured. He relies on data from the National
Crime Victimization Survey and the Uniform Crime Reporting System. Sherman describes how criminal behavior tends to be concentrated
in inner-city neighborhoods. He contends that “it is misleading to compare homicide rates across cities or to look at national
homicide rates without disaggregating them by the factors that are most strongly correlated with their existence.” Although
individual characteristics, such as age, race, and income, are important, he notes that “the effects of those characteristics
are magnified by location and space.” 相似文献