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11.
Subjects imagined situations in which they reported enjoying themselves either alone or with others. Electromyographic (EMG) activity was recorded bilaterally from regions overlying thezygomatic major muscles responsible for smiling. Controlling for equal rated happiness in the two conditions, subjects showed more smiling in high-sociality than low-sociality imagery. In confirming imaginary audience effects during imagery, these data corroborate hypotheses that solitary facial displays are mediated by the presence of imaginary interactants, and suggest caution in employing them as measures of felt emotion.Avery Gilbert and Amy Jaffey had compelling insights throughout the course of study. We thank Paul Ekman, Carroll Izard, and Paul Rozin for extensive comments on earlier drafts. We also thank Bernard Apfelbaum, Jon Baron, Janet Bavelas, John Cacioppo, Linda Camras, Dean Delis, Rob DeRubeis, Alan Fiske, Stephen Fowler, Greg McHugo, Harriet Oster, David Premack, W. John Smith, and David Williams for their valuable comments and suggestions.  相似文献   
12.
"The study compares determinants of internal and international migration intentions, drawing upon interview data from a sample of adults in Ilocos Norte, a largely rural province in the Philippines. A regression model is applied to test the relative determinants of intentions to migrate to Manila and to Hawaii. The study is based on a value-expectancy model of migration decision making. The results document the importance of subjective expectations related to the attainment of different values and goals in Manila and Hawaii."  相似文献   
13.
GM Foods and the Misperception of Risk Perception   总被引:3,自引:0,他引:3  
Public opposition to genetically modified (GM) food and crops is widely interpreted as the result of the public's misperception of the risks. With scientific assessment pointing to no unique risks from GM crops and foods, a strategy of accurate risk communication from trusted sources has been advocated. This is based on the assumption that the benefits of GM crops and foods are self-evident. Informed by the interpretation of some qualitative interviews with lay people, we use data from the Eurobarometer survey on biotechnology to explore the hypothesis that it is not so much the perception of risks as the absence of benefits that is the basis of the widespread rejection of GM foods and crops by the European public. Some respondents perceive both risks and benefits, and may be trading off these attributes along the lines of a rational choice model. However, for others, one attribute-benefit-appears to dominate their judgments: the lexicographic heuristic. For these respondents, their perception of risk is of limited importance in the formation of attitudes toward GM food and crops. The implication is that the absence of perceived benefits from GM foods and crops calls into question the relevance of risk communication strategies for bringing about change in public opinion.  相似文献   
14.
We propose a multiple imputation method to deal with incomplete categorical data. This method imputes the missing entries using the principal component method dedicated to categorical data: multiple correspondence analysis (MCA). The uncertainty concerning the parameters of the imputation model is reflected using a non-parametric bootstrap. Multiple imputation using MCA (MIMCA) requires estimating a small number of parameters due to the dimensionality reduction property of MCA. It allows the user to impute a large range of data sets. In particular, a high number of categories per variable, a high number of variables or a small number of individuals are not an issue for MIMCA. Through a simulation study based on real data sets, the method is assessed and compared to the reference methods (multiple imputation using the loglinear model, multiple imputation by logistic regressions) as well to the latest works on the topic (multiple imputation by random forests or by the Dirichlet process mixture of products of multinomial distributions model). The proposed method provides a good point estimate of the parameters of the analysis model considered, such as the coefficients of a main effects logistic regression model, and a reliable estimate of the variability of the estimators. In addition, MIMCA has the great advantage that it is substantially less time consuming on data sets of high dimensions than the other multiple imputation methods.  相似文献   
15.
Early in development, children explore and combine objects in increasingly complex ways. One manual skill, object construction, represents a major shift in how objects are explored relative to other objects. Despite recent connections with cognitive functioning such as spatial skills, the development of object construction ability has rarely been studied and its trajectory has not been adequately described. The purpose of this study was to describe the development of three types of object construction (stacking, nesting, and affixing) across 5 monthly infant visits and 7 monthly toddler visits using a longitudinal design and a large sample size. Infants (10–14 months, = 131) and toddlers drawn from the infant sample (18–24 months, = 65) were given sets of age‐appropriate toys each of which elicited at least one type of constructive play. We described success at different construction tasks and identified trends for construction skill for infant and toddler development using multilevel modeling. We found that each of the three construction actions developed in unique ways across the 10‐ to 24‐month period. Infant construction skill predicted the development of toddler skill, but toddler construction skill diverged from infant trajectories. We discuss the role of combination strategies in the development of object construction skill and how object construction could be related to other domains of development.  相似文献   
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17.
This article examines how childhood innocence is taken up in (92) memories of undergraduate students across four sites in the US and Canada. Drawing from Foucault's theory of discourse, we examine how three themes—innocence as not knowing, innocence as being provided for, and loss of innocence as exposure to adversity—construct childhood as the absence of conflict, which perpetuates the myth of an innocence/experience binary and encourages a deficit perspective of childhood. These findings contribute to teacher education and childhood studies by highlighting the importance of interrogating adult memories in order to disrupt normative assumptions about children.  相似文献   
18.
To recover a low-rank structure from a noisy matrix, truncated singular value decomposition has been extensively used and studied. Recent studies suggested that the signal can be better estimated by shrinking the singular values as well. We pursue this line of research and propose a new estimator offering a continuum of thresholding and shrinking functions. To avoid an unstable and costly cross-validation search, we propose new rules to select two thresholding and shrinking parameters from the data. In particular we propose a generalized Stein unbiased risk estimation criterion that does not require knowledge of the variance of the noise and that is computationally fast. A Monte Carlo simulation reveals that our estimator outperforms the tested methods in terms of mean squared error on both low-rank and general signal matrices across different signal-to-noise ratio regimes. In addition, it accurately estimates the rank of the signal when it is detectable.  相似文献   
19.
Public health relies on sample surveys to monitor the health of populations and investigate factors that contribute to population health and illness. Such investigations require surveying individuals who are selected in ways that support statistical inference to the population. Faced with rising costs and declining participation, survey researchers are exploring economical ways to recruit samples that validly represent larger populations. The current report describes an innovative resource, the Colorado Adult Population Sample–Survey Research Registry, which maintains survey access to respondents from a probability-based state health survey. We describe recruitment and retention strategies, explore representativeness, report several studies that used the registry, and discuss future directions.  相似文献   
20.
A number of studies have suggested breastfed infants have improved bonding and attachment or cognitive development outcomes. However, mechanisms by which these differences might develop are poorly understood. We used maternal time use data to examine whether exclusively breastfeeding mothers spend more time in close interactive behaviors with their infants than mothers who have commenced or completed weaning. Mothers (188) participating in a time use survey recorded infant feeding activities for 24 h over a 7 day period using an electronic device. Tracking was conducted at 3, 6, and 9 months postpartum. Data was collected for maternal activities including infant feeding and time spent in emotional care. The mothers of exclusively breastfed infants aged 3–6 months fed them frequently and total time spent in breastfeeding averaged around 17 h a week. Maternal time spent in emotional care was also substantial, and found to correlate positively with time spent breastfeeding. Exclusively breastfed infants received greatest amounts of emotional care from their mother, and exclusively formula fed infants the least. Mixed fed infants received more emotional care time than formula fed infants, but less than fully breastfed infants. These findings may help explain the differential cognitive developmental outcomes reported in the medical literature for breastfed and non breastfed infants.  相似文献   
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