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991.
Objective. Anti‐Americanism has been subjected to minimal statistical analysis. Further, scant attention is paid to what constitutes anti‐Americanism for Americans. The objective of this article is to measure Americans' perceptions of anti‐Americanism. Methods. Using a range of quantitative methods, including Pearson's correlation coefficient, Shannon's entropy measure, and Cohen's d statistics, we measure students' evaluations of editorial cartoons after 9/11. Twin measures of message and equity, along with participant and cartoon variables, are used to calibrate anti‐Americanism in Spanish and U.S. editorial cartoons. Results. Our results indicate that message ratings, that is, anti‐ or pro‐American, were more dependent on the nature of the cartoons than of the participants. White males rated these editorial cartoons as more equitable than other participants. The study shows that Spanish cartoons were rated significantly more anti‐American. Conclusion. The article concludes that the use of U.S. icons is key to seeing anti‐Americanism, along with gender, race, and origin of cartoon. 相似文献
992.
Commodity prices often fluctuate significantly from one purchasing opportunity to the next. These fluctuations allow firms to benefit from forward buying (buying for future demand in addition to current demand) when prices are low. We propose a combined heuristic to determine the optimal number of future periods a firm should purchase at each ordering opportunity in order to maximize total expected profit when there is uncertainty in future demand and future buying price. We compare our heuristic with existing methods via simulation using real demand data from BlueLinx, a two-stage distributor of building products. The results show that our combined heuristic performs better than any existing methods considering forward buying or safety stock separately. We also compare our heuristic to the optimal inventory management policy by full enumeration for a smaller data set. The proposed heuristic is shown to be close to optimal. This study is the first to decide both the optimal number of future periods to buy for uncertain purchase price and the appropriate purchasing quantity with safety stock for uncertain demand simultaneously. The experience suggests that the proposed combined heuristic is simple and can be very beneficial for any company where forward buying is possible. 相似文献
993.
994.
Breaking ground from all previous studies, we estimate a time-varying Vector Autoregression model that examines the time-period 1270–2016 — the entire economic history of the U.K. Focusing on permanent and transitory shocks in the economy, we study the fluctuation in conditional volatilities and time-varying long-run responses of output growth and inflation. Unlike all previous studies that use time invariant linear models, our approach reveals that the pre 1600 period is a turbulent economic period of high volatility that is only repeated in the 20th century. The repeating patterns in the conditional volatilities follow from aggregate supply shocks, while most of the inflation responses follow from aggregate demand shocks. Thus, we uncover that despite the technological growth and the various changes in the structure of the U.K. economy in the last century, the recurring patterns call for an examination of the true impact of the various policies on the economy. 相似文献
995.
Mark Schneider Jonathan W. Leland Nathaniel T. Wilcox 《Journal of Risk and Uncertainty》2018,57(2):133-151
In his exposition of subjective expected utility theory, Savage (1954) proposed that the Allais paradox could be reduced if it were recast into a format which made the appeal of the independence axiom of expected utility theory more transparent. Recent studies consistently find support for this prediction. We consider a salience-based choice model which explains this frame-dependence of the Allais paradox. We then derive the novel prediction that the presentation format responsible for reductions in Allais-style violations of expected utility theory will also reduce Ellsberg-style violations of subjective expected utility theory. This format makes the appeal of Savage’s “sure thing principle” more transparent. We design an experiment to test this prediction and find strong support for such frame-dependence of ambiguity aversion in Ellsberg-style choices. In particular, we observe markedly less ambiguity-averse behavior in Savage’s matrix format than in a more standard “prospect” format. This finding poses a new challenge for the leading models of ambiguity aversion. 相似文献
996.
Tebeau M 《Journal of social history》2010,44(2):327-350
Perhaps the world's first peace garden, the Cleveland Cultural Gardens embody the history of twentieth-century America and reveal the complex interrelations between art and place. This essay uses the Cleveland Cultural Gardens as a lens through which to explore how art and place have intersected over time. It explores how communities have negotiated questions of national, ethnic, and American identity and embedded those identities into the vernacular landscape. It considers how the particulars of place were embedded into a public garden and asks whether it is possible for public art to transcend its place—both in terms of geography and history. In some sense, the Gardens have transcended their place, but in others respects, their fortunes were bound inextricably to that place, to the economic, demographic, and cultural contours that shaped and reshaped Northern Ohio. As works of art, the Cleveland Cultural Gardens both have reflected the history of Cleveland and American industrial cities during the 20th century and revealed something of the dynamics that underscored the changing character of public art and gardens in American cities. 相似文献
997.
Using a subclass of the α-maximin expected-utility preference model, in which the decision maker’s degree of ambiguity and degree of pessimism are
each parameterized, we present a theory of religious choice in the Pascalian decision theory tradition, one that can resolve
dilemmas, address the “many Gods objection,” and address the ambiguity inherent in religious choice. Parameterizing both the
degree of ambiguity and the degree of pessimism allows one to examine how the two interact to impact choice, which is useful
regardless of the application. Applying this model to religious choice is a move beyond subjective expected-utility theory,
allowing us to show that a change in either the degree of ambiguity or the degree of pessimism can lead a decision maker to
“convert” from one religion to another. 相似文献
998.
Mark Ebden Armin Stranjak Stephen Roberts 《Journal of the Royal Statistical Society. Series C, Applied statistics》2010,59(1):163-173
Summary. We propose an approach for estimating the date of lost confidence of jet engines, which are devices with multiple components subject to disruption. A mixed Weibull distribution is estimated from a large data set subject to censoring at various times. Parametric uncertainty is derived analytically and mapped visually onto the functions of use in reliability theory, including the hazard function. We demonstrate the use of the method on a database of disruption times for components in 325 jet engines. 相似文献
999.
Causal inference approaches in systems genetics exploit quantitative trait loci (QTL) genotypes to infer causal relationships among phenotypes. The genetic architecture of each phenotype may be complex, and poorly estimated genetic architectures may compromise the inference of causal relationships among phenotypes. Existing methods assume QTLs are known or inferred without regard to the phenotype network structure. In this paper we develop a QTL-driven phenotype network method (QTLnet) to jointly infer a causal phenotype network and associated genetic architecture for sets of correlated phenotypes. Randomization of alleles during meiosis and the unidirectional influence of genotype on phenotype allow the inference of QTLs causal to phenotypes. Causal relationships among phenotypes can be inferred using these QTL nodes, enabling us to distinguish among phenotype networks that would otherwise be distribution equivalent. We jointly model phenotypes and QTLs using homogeneous conditional Gaussian regression models, and we derive a graphical criterion for distribution equivalence. We validate the QTLnet approach in a simulation study. Finally, we illustrate with simulated data and a real example how QTLnet can be used to infer both direct and indirect effects of QTLs and phenotypes that co-map to a genomic region. 相似文献
1000.
Kathryn Ellis 《Social Policy & Administration》2011,45(3):221-244
This reassessment of the continuing significance of Lipsky's (1980 ) work on ‘street‐level bureaucracy’ for frontline decision making is based on a retrospective review of the author's research on assessment practice in adult social care in England. The studies span the past two decades during which time successive governments have restructured and modernized social services departments. When these were established in 1970, they represented the high watermark of bureau‐professionalism – a mode of administration which dominated social welfare at the time Lipsky was writing. The subsequent dismantling of bureau‐professionalism calls into question the validity of his findings, and the author draws on her own research to assess conflicting views about the impact of social care reforms on the discretion which social workers exercise as street‐level bureaucrats. She concludes that the distinct types of discretion to emerge from her findings, represented in a taxonomy, are shaped by the differing micro environments of frontline practice which, in turn, affect the relative force of managerialism, professionalism and user empowerment in countering the defensive exercise of discretion described by Lipsky. Whilst her analysis affirms the continuing significance of Lipsky's analysis, it also points to the need for some revision to accommodate major shifts in welfare administration since the publication of his work. She highlights the potential relevance of these insights for investigating the next planned transformation of adult social care, personalization, as well as for the implementation literature more widely. 相似文献