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1.
我国粮食产后损失情况概述   总被引:1,自引:0,他引:1  
本文系统分析了粮食产后各环节损失的原因及损失量,针对相关粮食损失原因及状况,提出了减少粮食产后损失的措施及建议,以期为我国实现节粮减损提供支持。  相似文献   
2.
Aims: Depression is the most frequent comorbidity reported among patients with rheumatoid arthritis (RA). Comorbid depression negatively impacts RA patients’ health-related quality-of-life, physical function, mental function, mortality, and experience of pain and symptom severity. The objective of this study was to assess healthcare utilization, expenditures, and work productivity among patients with RA with or without depression.

Materials and methods: Data from adult patients who had at least two visits each related to RA and depression over a 1-year period were extracted from the Truven Health MarketScan research databases. Outcomes comprised healthcare resource utilization, work productivity loss, and direct healthcare costs comparing patients with RA with depression (n?=?3,478) vs patients with RA without depression (n?=?43,222).

Results: Patients with RA and depression had a significantly greater relative risk of hospitalization and number of all-cause and RA-related hospitalizations, utilization of emergency services, days spent in the hospital, physician visits, and RA-related surgeries compared with RA patients without depression. Patients with RA and depression had a higher risk of and experienced more events and days of short-term disability compared with patients without depression. The incremental adjusted annual all-cause and RA-related direct costs were $8,488 (95% CI = $6,793–$10,223) and $578 (95% CI = –$98–$1,243), respectively, when comparing patients with RA and depression vs RA only.

Limitations: The current analysis is subject to the known limitations of retrospective studies based on administrative claims data.

Conclusions: This study suggested increased healthcare utilization, work productivity loss, and economic burden among RA patients due to comorbid depression. These findings emphasize the importance of managing depression and including depression as a factor when devising treatment algorithms for patients with RA.  相似文献   
3.
This article investigates which type of loss function is consistent with the hypothesis that major exchange rate forecasts, i.e. the euro, the British pound, and the Japanese yen vis-à-vis the US dollar, are rational. We apply a comprehensive data set, which also allows us to examine different forecast horizons and heterogeneity of forecasters.  相似文献   
4.
多径效应导致基于信号接收强度(RSSI)的室内定位方法精度不高,采用更细粒度的物理层信道状态信息(CSI)可以区分不同路径,提高定位精度。在已有基于CSI室内定位方法的基础上,通过改进对数距离路径损耗模型,得到CSI与传输距离的关系,并结合目标位置所测得的CSI值回归出目标与发射端的距离,最后通过三边定位法预测出目标的位置坐标。实验表明,相比基于RSSI的定位方法以及已有的基于CSI的定位方法,所提方法2 m以内的误差概率提高了将近40%和20%,有效提高了定位精度。  相似文献   
5.
The increase in interconnectivity and developments in technology have caused cyber security to become a universal concern. This paper highlights the dangers of the evolution of cyber risk, the challenges of quantifying the impact of cyber-attacks and the feasibility of the traditional actuarial methodologies for quantifying cyber losses. In this paper, we present a practical roadmap for assessing cyber risk, a roadmap that emphasizes the importance of developing a company and culture-specific risk and resilience model. We develop a structure for a Bayesian network to model the financial loss as a function of the key drivers of risk and resilience. We use qualitative scorecard assessment to determine the level of cyber risk exposure and evaluate the effectiveness of resilience efforts in the organization. We highlight the importance of capitalizing on the knowledge of experts within the organization and discuss methods for aggregating multiple assessments. From an enterprise risk management perspective, impact on value should be the primary concern of managers. This paper uses a value-centric/reputational approach to risk management rather than a regulatory/capital-centric approach to risk.  相似文献   
6.
We explore how futures traders make a tradeoff between risk and return by examining their risk-taking in the action. By applying a novel measure to their trade-by-trade transactions to capture their tendency in risk-taking, we find a general tendency to reduce risk-taking by cutting positions when facing losses or gains, and the tendency is stronger in the case of losses. However, great variations exist among traders in the risk-taking tendency and the results for trading are opposite for profitable and unprofitable traders. For the unprofitable, more risk-taking by trading more actively leads to greater losses. This is concrete evidence for the prevailing belief in the literature that trading too much, arguably due to overconfidence, is hazardous to investor's wealth. Contrary to that belief, however, we find fresh evidence that more active trading by the profitable traders leads to greater profits, suggesting their trades are likely based on ability and skills.  相似文献   
7.
We study a bilateral negotiation set-up where, at a bargaining impasse, the disadvantaged party chooses whether to escalate the conflict or not. Escalation is costly for both parties, and it results in a random draw of the winner of the escalated conflict. We derive the behavioral predictions of a simple social utility function, which is convex in disadvantageous inequality, thus connecting the inequity aversion and the prospect theory models. Our causal laboratory evidence is, to a large extent, consistent with the predicted effects. Among other things, the model predicts that the escalation rate is higher when escalation outcomes are riskier, and that the disagreement rate is lower when the cost of escalating the conflict is higher.  相似文献   
8.
A combined travel cost – contingent behaviour survey of residents and tourists in Catalonia is conducted on-site to examine the effects on beach recreational demand of developing an offshore wind farm (OWF) project. The survey considers four potential OWF scenarios with different degrees of visual impact. We allow for heterogeneity in trip preferences among individuals and control for on-site sampling through the use of a random parameters negative binomial (RPNB) model and a Multivariate Poisson log-normal (MPLN) model, respectively. The welfare measures derived from the RPNB model relate to the current beach users only, whereas those from the MPLN model refer to the general population of residents and tourists in Catalonia. The results show the importance of the specific place of location of the OWF project and how the installation of wind turbines would significantly decrease the demand for trips, depending on their degree of visual impacts, leading to a substantial welfare loss. However, the results also show that the project mainly would cause a displacement of trips to other beaches within Catalonia rather than outside Catalonia and that the welfare per trip measures generated by the RPNB and MPLN models substantially differ. Policy implications of these findings are discussed.  相似文献   
9.
Forecasts are a central component of policymaking; the Federal Reserve's forecasts are published in a document called the Greenbook. Previous studies of the Greenbook's inflation forecasts have found them to be rationalizable but asymmetric if considering particular subperiods, for example, before and after the Volcker appointment. In these papers, forecasts are analyzed in isolation, assuming policymakers value them independently. We analyze the Greenbook forecasts in a framework in which the forecast errors for different variables are allowed to interact. We find that allowing the losses to interact makes the unemployment forecasts virtually symmetric, the output forecasts symmetric prior to the Volcker appointment, and the inflation forecasts symmetric after the onset of the Great Moderation.  相似文献   
10.
Using unique survey data, we find that a longer investment horizon (6–10 years and 11+ years) reduces the likelihood of exhibiting myopic loss aversion (MLA) compared to an investment horizon of less than 2 years. In addition, we find that investors with higher levels of assets under management (AUM) are less likely to exhibit MLA compared to the lowest AUM quartile.  相似文献   
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