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91.
Supporting healthy lifestyle behaviours is a key aspect of preventing type 2 diabetes which disproportionately affects disadvantaged groups from a younger age. Formative participatory research was undertaken to design a program for young Aboriginal people in a remote town in North West Australia with a high level of health needs and relatively few prevention initiatives. Focus groups and advisory discussions with Aboriginal community members were used to determine the nature of the program. The need for a comprehensive program was consistently expressed and limited healthy lifestyle knowledge and difficulties with healthy eating influenced by food environments were noted to be important. With guidance from the Derby Aboriginal Health Service, findings were integrated with previous international research evidence to develop a program tailored to local Aboriginal people aged 15–25 years and refine it after piloting. This 8-session program, ‘Maboo wirriya, be healthy’ involved an education component consistent with the US Diabetes Prevention Program and practical activities including group exercise. Changes to program structure and documentation were made after piloting for future use. The community-directed approach used in this study is vital to ensure relevance of localised chronic disease prevention programs in a range of settings.  相似文献   
92.
Adverse childhood experiences might have long-lasting effects on decisions under uncertainty in adult life. Merging the European Survey on Health, Ageing and Retirement with data on conflict events during the Second World War, and relying on region-by-cohort variation in war exposure, we show that warfare exposure during childhood is associated with lower financial risk taking in later life. Individuals who experienced war episodes as children hold less – and are less likely to hold – stocks, but are more likely to hold life insurance, compared to non-exposed individuals. Effects are robust to the inclusion of potential mediating factors, and are tested for nonlinearity and heterogeneity. Moreover, we provide evidence of hedonic adaptation to war, as high and low intensity of war exposure have comparable long-term effects. We also document that war exposure in childhood increases sensitivity to financial uncertainty since exposed-to-war individuals are less likely to hold stocks after periods of high volatility. Finally, we shed light on the most likely mechanism in the relationship between war exposure and financial risk taking – i.e., enhanced sensitivity to uncertainty – and we show that preferences, and not beliefs, channel this relationship.  相似文献   
93.
In dynamic contests, strategic momentum and psychological momentum potentially coexist, which makes it difficult to distinguish between the two. We employ the setting of professional tennis, which allows us to separate psychological from strategic momentum. In tennis, converting a break point potentially triggers both strategic momentum—due to a change in the relative position of the players—and psychological momentum—due to a change in the perception of the players. To distinguish between these two momentum types, we employ exogenously given interruptions. Interruptions are predicted to affect psychological momentum negatively, while leaving strategic momentum unaffected. Using 4930 game-by-game observations from 141 Grand Slam men’s single matches, we show that the breaking players’ probability of winning a game increases after converting a break point, which provides evidence for momentum. Moreover, we show that this momentum effect is negatively affected by an interruption. Thus, psychological momentum seems to be the main trigger leading to a performance increase after a converted break point.  相似文献   
94.
Abstract

In the case where strength and stress both follow exponential distributions, this paper considers the maximum likelihood estimator (MLE) of the system reliability based on L ranked set sampling (LRSS). The proposed MLE is shown to have existence, uniqueness and asymptotic normality, and its asymptotic variance is obtained by the Fisher information matrix of LRSS. The values of asymptotic relative efficiencies show that the proposed MLE is always more efficient than the MLE using simple random sampling (SRS). However, the MLE using LRSS cannot be written in closed form. Therefore, the modified MLE is proposed using the technique replaced some terms in the maximum likelihood equations by their expectations. The newly modified MLE using LRSS is shown to be superior to the MLE using SRS. Finally, the proposed method is applied to a real data set on metastatic renal carcinoma study.  相似文献   
95.
《Journal of Policy Modeling》2020,42(6):1187-1207
This paper investigates the determinants of countries’ choices of monetary policy framework. A brief narrative focused on groupings of countries motivates an econometric analysis which draws on previous work on the determinants of exchange rate regimes, bringing in standard factors as well as the trade networks of potential anchor currency blocs and the financial market depth that are emphasised in the narrative. The model turns out to be able to predict three quarters of countries’ choices, and there is no obvious systematic pattern in the errors. The results have important implications for how countries should choose their monetary policy frameworks.  相似文献   
96.
The idea that language skills support school readiness, predicting later self‐regulation and academic success, is widely accepted. Although vocabulary is often emphasized in the developmental literature, the ability to use language appropriately in the classroom, or social communication skills, may also be critical. This article examined longitudinal contributions of children's vocabulary and social communication skills, from preschool to kindergarten, to kindergarten academic achievement (reading and math) and self‐regulation (executive functions and learning behaviors). Participants were 164 children (14% Latinx, 30% Black, 56% White; 57% girls) enrolled in Head Start programs. Results revealed that initial levels and growth in vocabulary and communication skills predicted better academic achievement. Social communication skills uniquely predicted self‐regulation, after accounting for vocabulary. We discuss potential mechanisms for these links and recommend that strategies to build social communication skills be incorporated in preschool interventions promoting school readiness.  相似文献   
97.
Microbiological food safety is an important economic and health issue in the context of globalization and presents food business operators with new challenges in providing safe foods. The hazard analysis and critical control point approach involve identifying the main steps in food processing and the physical and chemical parameters that have an impact on the safety of foods. In the risk‐based approach, as defined in the Codex Alimentarius, controlling these parameters in such a way that the final products meet a food safety objective (FSO), fixed by the competent authorities, is a big challenge and of great interest to the food business operators. Process risk models, issued from the quantitative microbiological risk assessment framework, provide useful tools in this respect. We propose a methodology, called multivariate factor mapping (MFM), for establishing a link between process parameters and compliance with a FSO. For a stochastic and dynamic process risk model of in soft cheese made from pasteurized milk with many uncertain inputs, multivariate sensitivity analysis and MFM are combined to (i) identify the critical control points (CCPs) for throughout the food chain and (ii) compute the critical limits of the most influential process parameters, located at the CCPs, with regard to the specific process implemented in the model. Due to certain forms of interaction among parameters, the results show some new possibilities for the management of microbiological hazards when a FSO is specified.  相似文献   
98.
Sales are a widespread and well‐known phenomenon documented in several product markets. This paper presents a novel rationale for sales that does not rely on consumer heterogeneity, or on any form of randomness to explain such periodic price fluctuations. The analysis is carried out in the context of a simple repeated price competition model, and establishes that firms must periodically reduce prices in order to sustain collusion when goods are storable and the market is large. The largest equilibrium profits are characterized at any market size. A trade‐off between the size of the industry and its profits arises. Sales foster collusion, by magnifying the inter‐temporal links in consumers' decisions.  相似文献   
99.
We consider a market in which domestic buyers negotiate contracts with foreign sellers, and explore how trade quotas can help to increase the buyers' countervailing power. We use the Shapley value to describe bargaining power and the distribution of the trade surplus in such a bilateral oligopoly. By exploiting strategic externalities among the buyers, bilateral trade quotas can improve the buyers' bargaining positions. In contrast, aggregate trade restrictions on all buyers' trade never improve buyer surplus. Minimum quotas on imports from fringe suppliers can benefit nonaffected buyers, as these enjoy positive externalities. We apply these insights to the E.U. market for natural gas and show that the effects of trade quotas on E.U. gas importers' power can be significant.  相似文献   
100.
R2是最近十几年迅速发展的一个研究课题,其研究取向从纯粹的计量经济学符号演变为股价同步性特征变量,并与公司特质信息含量联系起来,赋予了全新的内涵.学者们通过跨学科的交叉与融合,从法与金融理论、委托代理理论、信息不对称理论、公司治理理论等视角对R2背后的生成机制、作用渠道和影响后果展开富有成效的研究.本文首先梳理从资产定价模型到R2,再从R2到股价同步性中间的学理关系和因果顺承,接着回顾了关于R2形成机理与经济后果的相关讨论,然后对R2的学术争论进行总结和评述,最后就R2的溯源问题、以及文化与政治潜在影响对未来R2研究提出展望.  相似文献   
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