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831.
This paper addresses three topics to which researchers should turn their attention in regard to the dependent variable of giving and volunteering. The first is to develop an expanded definition of philanthropy revolving around the notion of gift and the relations of exchange and around the theological virtue of charity and the emotional dispositions of care, altruism, and love of neighbour. The second is to attend to measurement problems in regard to operationalising giving and volunteering; obtaining comparable information from givers and non-givers; improving the reliability of the data, including an effort to reduce the amount of missing data; and establishing a consistent unit of analysis. The third direction is to conduct some innovative research activity to obtain better measures and understandings of giving and volunteering, including development of a diary study, closer analysis of the relationship between class and giving, and attention to measuring the social effects or outcomes of philanthropic activity.An earlier version of this paper was presented at the Conference on Charitable Statistics sponsored by the New York University School of Law Program on Philanthropy and the Law, Indiana University Center on Philanthropy, Duke University Center for the Study of Philanthropy and Voluntarism, Washington, D.C., 8 May 1992.  相似文献   
832.
Results are reported from a preliminary study testing a new technology for survey data collection: audio computer-assisted self interviewing. This technology has the theoretical potential of providing privacy (or anonymity) of response equivalent to that of paper self-administered questionnaires (SAQs). In addition, it could offer the advantages common to all computer-assisted methods such as the ability to implement complex questionnaire logic, consistency checking, etc.. In contrast to Video-CASI, Audio-CASI proffers these potential advantages without limiting data collection to the literate segment of the population. In this preliminary study, results obtained using RTI's Audio-CASI system were compared to those for paper SAQs and for Video-CASI. Survey questionnaires asking about drug use, sexual behavior, income, and demographic characteristics were administered to a small sample (N = 40) of subjects of average and below-average reading abilities using each method of data collection. While the small sample size renders many results suggestive rather than definitive, the study did demonstrate that both Audio- and Video-CASI systems work well even with subjects who do not have extensive familiarity with computers. Indeed, respondents preferred the Audio- and Video-CASI to paper SAQs. The computerized systems also eliminated errors in execution of "skip" instructions that occurred when subjects completed paper SAQs. In a number of instances, the computerized systems also appeared to encourage more complete reporting of sensitive behaviors such as use of illicit drugs. Among the two CASI systems, respondents rated Audio-CASI more favorably than Video-CASI in terms of interest, ease of use, and overall preference.  相似文献   
833.
Aviation Risk Perception: A Comparison Between Experts and Novices   总被引:2,自引:0,他引:2  
This article describes an exploratory investigation of the risk perceptions of experts and novices in relation to helicopter operations, under conditions where the participants are matched on various characteristics previously found to affect perceptions, such as demographic, gender, and background factors. The study reports considerable evidence of perceptual differences between the two participant groups (i.e., expert pilots and candidate pilots). We find that the experts' perceptions of relative risks are more veridical, in terms of their higher correlation with the true relative frequencies. A significant positive correlation between the flight hours and the contextual risk-taking tendency is also shown, leading the experienced pilots' choices toward risky alternatives in scenarios--a potential result of their overconfidence based on superior task performance. Possible explanations are offered for the findings and potential avenues for future research are identified.  相似文献   
834.
This paper provides evidence of links between the nature of strategic formulation within firms and subsequent plant performance. The research focuses on how some firms have managed to link operations and supply into an integrated set of mutually supportive strategies. In the current competitive arena firms can no longer rely wholly on internal resource-based capabilities but must instead form strategic partnerships within what are often complex networks. The paper explores how operations and supply functions have pursued parallel paths but have often not been fully integrated within firms. It is argued that such integration, which forms part of what has been termed strategic resonance , can reap enormous benefits in terms of plant-level capabilities for firms.  相似文献   
835.
Investing Profitably in China: is it Getting Harder?   总被引:1,自引:0,他引:1  
Using information from the Toyo Keizai, this article studies the performance of 2,962 foreign subsidiaries across the period 1985-1999 to show a picture of declining profitability from foreign direct investment by MNE’s in China. Despite the influence of macro-level factors, such as the historically fluctuating performance of the Chinese economy, we observed that of the many factors that may affect profitability, subsidiary-specific factors had the greater influence. The findings suggest that there are significant benefits for early entrants into the market, but caution against the use of high majority ownership control. Other evidence showed that larger subsidiaries tended to perform better. Managerial implications for MNEs and the future prospects of foreign direct investment in China are discussed.Since China opened up to the outside world in 1979, it has been attracting increasing amounts of foreign direct investment (FDI), and after 1993 became the second largest recipient of FDI flows in the world. Meanwhile, a major participant in the upsurge in global foreign direct investment in the 1990s was Japan. By the mid-1990s, Japan became the second largest FDI source country in the world behind the United States. China, in particular, has become a major destination for Japan’s direct investments, absorbing one-ninth of all Japanese foreign investments at the end of 1996.1Studying Japan’s worldwide direct foreign investment, we found that the proportion of profitable Japanese subsidiaries in China has been declining. In fact, this was the only part of the world where this was the case. While over 71 percent of Japanese subsidiaries in China claimed profits in 1992, the percentage steadily slipped to around 50 percent by 1999 (see Table 1). This poses two interesting questions. Is it really getting harder to invest profitably in China? And what could have influenced the profit performance of foreign subsidiaries in China?  相似文献   
836.
Early formulations of conjoint models focused on part-worth estimation at the individual level. As the methodology's popularity grew so did industry demands for increasingly larger numbers of attributes and levels. In response to these demands, new approaches, based on partial or full data aggregation (such as clusterwise/latent class conjoint and choice-based conjoint), have appeared. This paper suggests that pooled-data models will often be successful in predicting market shares when researchers employ monotonic attributes. In these cases more of a good attribute (or less of a bad attribute) is always more preferred. In the more realistic case, in which some of the attributes may be nonmonotonic, we find that data aggregation does not predict holdout sample preferences as well as individual part-worth models.  相似文献   
837.
We suppose a case is to be compared with controls on the basis of a test that gives a single discrete score. The score of the case may tie with the scores of one or more controls. However, scores relate to an underlying quantity of interest that is continuous and so an observed score can be treated as the rounded value of an underlying continuous score. This makes it reasonable to break ties. This paper addresses the problem of forming a confidence interval for the proportion of controls that have a lower underlying score than the case. In the absence of ties, this is the standard task of making inferences about a binomial proportion and many methods for forming confidence intervals have been proposed. We give a general procedure to extend these methods to handle ties, under the assumption that ties may be broken at random. Properties of the procedure are given and an example examines its performance when it is used to extend several methods. A real example shows that an estimated confidence interval can be much too small if the uncertainty associated with ties is not taken into account. Software implementing the procedure is freely available.  相似文献   
838.
In this paper, we develop a numerical method for evaluating the large sample bias in estimated regression coefficients arising due to exposure model misspecification while adjusting for measurement errors in errors-in-variable regression. The application of the proposed method has been demonstrated in the case of a logistic errors-in-variable regression model. The method is based on the combination of Monte-Carlo, numerical and, in some special cases, analytic integration techniques. The proposed method facilitates the investigation of the limiting bias in the estimated regression parameters based on a single data set rather than on repeated data sets as required by the conventional repeated sample method. Simulation studies demonstrate that the proposed method provides very similar estimates of bias in the estimated regression parameters under exposure model misspecification in logistic errors-in-variable regression with a higher degree of precision as compared to the conventional repeated sample method.  相似文献   
839.
840.
Tree bucking is the initial production process in converting felled trees into useable wood products. This process has been previously modelled as a dynamic programming problem. Unlike other production problems that have been modelled as dynamic programming problems, there have been no serious attempts to formulate this problem as a branch-and-bound model and then examine the model's performance. This research develops the tree bucking problem as a branch-and-bound model to be tested by varying several parameters. The testing is performed in two phases: (1) a sensitivity analysis is performed to test two key parameters used by the model, and (2) branching strategies are tested on various problem scenarios. The size of the solution sets searched by the technique vary from as low as 40 to as many as 41,000 possible combinations.  相似文献   
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