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71.
Based on the multi-item Food Choice Questionnaire (FCQ) originally developed by Steptoe and colleagues (1995), the current study developed a single-item FCQ that provides an acceptable balance between practical needs and psychometric concerns. Studies 1 (N = 1851) and 2 (2a (N = 3290), 2b (N = 4723), 2c (N = 270)) showed that the single-item FCQ scale has good convergent and discriminant validity. Generally, the results showed the highest correlations with the related multi-item dimensions (>0.40). Study 2 refined the scale. Only the items for convenience (Study 2a), sensory appeal (Study 2b) and mood (Study 2c) needed to be revised (as Study 1 showed a correlation between the multi-item and the single-item below the threshold of 0.60). The results also showed comparable predictive validity. Both methods revealed similar association patterns between food motives and consumption behaviours (Fisher’s z tests revealed agreements of 86.2% for Study 1, 92.9% for Study 2a and 100% for Studies 2b and 2c). Study 3 (N = 6062) showed an example of the added value of a context-specific application for the single-item FCQ. Different motives were shown to be relevant across contexts, and the context-specific motives had additional explained variance beyond the general multi-item FCQ. Studies 2b and 3 also showed the performance of the single-item FCQ in an international context. In sum, the results indicate that the single-item FCQ can be used as a flexible and short substitute for the multi-item FCQ. The study also discusses the conditions that should be considered when using the single-item scale. 相似文献
72.
Refurbishment and quality recovery, as two important strategies of reverse logistics, have been widely used for consumer durables, especially consumer electronics. This trend is driven by manufacturers’ profit-seeking behaviours and the increasing environmental concerns of society. This study investigates and compares the optimal emergence of these two strategies when product quality is endogenous. Model analyses provide several notable insights. First, we find that the refurbishment strategy dominates the quality recovery strategy when the fraction of the recoverable quality-inducing components in the defective product is low enough. Moreover, when the refurbishment strategy emerges as the optimum, the quality and price of the new product as well as the total realised sales of both new and refurbished products are consistently higher than those with the quality recovery strategy. In addition, when either the refurbishment or quality recovery strategy emerges as the optimum, the overall consumer surplus is also enhanced. Finally, in the model generalisation, we show that a synthetic strategy with which some of the returned defective products are refurbished and others are remanufactured through quality recovery can certainly increase the manufacturers’ profit compared to either one of them when the fraction of the recoverable quality-inducing components in the defective product is moderate. 相似文献
73.
王云蔚 《北京印刷学院学报》2013,21(3):21-26
伴随着我国综合国力和科研能力的提升,我国已成为科技期刊大国,但是其发展不能适应我国科技论文强国地位的要求,为此,必须走一条市场化经营之路。在现有科技期刊体制下,理顺各种关系,成为独立的市场化主体、构建独立的国家级科技期刊评价标准,建立利益共同体实现规模经营,增强品牌意识,提升品牌效应,完善市场化经营能力和方式,是科技期刊市场化经营的路径选择。 相似文献
74.
Previous research has demonstrated that older adults prefer less autonomy and seek less information when making decisions on their own relative to young adults (for a review, see M. Mather, 2006). Would older adults also prefer fewer options from which to choose? The authors tested this hypothesis in the context of different decision domains. Participants completed a choice preferences survey in which they indicated their desired number of choices across 6 domains of health care and everyday decisions. The hypothesis was confirmed across all decision domains. The authors discuss implications from these results as they relate to theories of aging and health care policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Adaptive decision making requires that contingencies between decision options and their relative assets be assessed accurately and quickly. The present research addresses the challenging notion that contingencies may be more visible from small than from large samples of observations. An algorithmic account for such a seemingly paradoxical effect is offered within a satisficing-choice framework. Accordingly, a choice is only made when the sample contingency describing the relative evaluation of the 2 options exceeds a critical threshold. Small samples, because of the high dispersion of their sampling distribution, facilitate above-threshold contingencies. Across a broad range of parameters, the resulting small-sample advantage in terms of hits is stronger than their disadvantage in false alarms. Computer simulations and experiments support the model predictions. The relative advantage of small samples is most apparent when information loss is low, when the threshold is high relative to the ecological contingency, and when the sampling process is self-truncated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
77.
Utility functions, which relate subjective value to physical attributes of experience, are fundamental to most decision theories. Seven experiments were conducted to test predictions of the most widely assumed mathematical forms of utility (power, log, and negative exponential), and a function proposed by Rachlin (1992). For pairs of gambles for real monetary gains, undergraduate and nonstudent subjects either reported an equalizing amount for 1 outcome that made the gambles subjectively equal or chose between gambles where the amounts were varied across trial, which allowed the equalizing amount to be estimated from their pattern of choices. Using a novel method that eliminates several limitations of previous research, I manipulated the outcomes across trials such that each type of utility function predicted a linear relationship between the equalizing amounts and the amounts of the other outcomes, and made point predictions for either the slope or intercept of that relationship. In a meta-analysis across experiments, systematic departures from the point predictions were observed for each type of utility function. Thus, the data imply that despite their historical importance and incorporation in many psychological and economic decision theories, the most widely assumed models of utility are incorrect. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
78.
通过非线性时间序列的策略分析,按照神经网络的路径选择特点和非线性数据的分析方法进行总体评估,提出基于RBF神经网络路径安全策略. 相似文献
79.
在压力0.15 MPa温度110℃时间为5 min的条件下,对烟梗进行了高压蒸梗处理,并采用同时蒸馏萃取、气相色谱-质谱/选择离子法(GC-MS/SIM)和内标法,对高压蒸梗膨胀处理前后中性香味成分进行了定性、定量对比分析,并进行感官质量评价。结果表明:高压蒸梗处理的烟梗中性香味成分总量、醛类、醇类和酯类均比常规处理烟梗中要高,尤其是2-甲基-四氢呋喃-3-酮、糠醛、糠醇、2-环戊烯-1,4-二酮、2-乙酰呋喃物质的含量显著增加。高压蒸梗处理对于改善烟梗的感官吸味品质具有明显的作用。 相似文献
80.
异步电机基于谐波磁场影响的槽配合综述 总被引:4,自引:0,他引:4
异步电机的槽配合与电机中谐波磁场有密切的关系。本文在谐波磁场分析的基础上,从研究异步电机定、转子槽配合对最小转矩、电磁振动和噪声及杂散损耗的影响出发,得出一系列合理选择槽配合规则,这些规则对异步电机优化设计具有指导意义。 相似文献