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991.
The present research proposes a new generalisation of the logistic model aiming at technology diffusion forecasting. Regarding criticisms and failures reported in the literature to apply logistic function for long-term forecasting, in our work we focused on short-term accuracy of forecast. To formulate the model, based on mathematical approximation, at first the differential equation governing the diffusion process is found and then by solving the derived differential equation, the forecast function is obtained. In all steps, mathematical tools from numerical analysis are used. We compared the New Generalized Logistic Model with eight of the most renowned models in the literature. The model led to more accurate fits and forecasts than those obtained from other models we applied for comparison.  相似文献   
992.
In the present research, Construal Level Theory is used to predict that consumers will mentally characterize incentive offers differently as a function of their redemption time frames. Data from two experiments indicate that concrete features, such as the face value of an offer or its mode of presentation (as a dollar figure or as a percentage discount), are prominent for incentives with short time frames but not for incentives with long ones. In the latter case, abstract features, such as the incentive’s goal congruity or fit with personal values, are more likely to influence responses.  相似文献   
993.
Many firms use online brand communities to support the launch of their new products. This study proposes a typology of firm-hosted online brand communities and examines whether such a classification system can improve predictions of new product success. A cross-industry analysis of 81 firm-hosted online brand communities shows that these communities reflect three archetypes. A subsequent survey of 170 community-hosting firms in the consumer durable goods industry reveals that the three types of communities are not equally important for new product success. Moreover, one archetype generally underperforms the other two as a new product support mechanism. Overall, the results demonstrate that firm-hosted online brand communities can be a predictor of new product success.  相似文献   
994.
Aims: This study aimed to estimate the cost of platelet transfusion in patients with chronic liver disease (CLD)-associated thrombocytopenia undergoing an elective procedure in the United States.

Materials and methods: The study was conducted in two parts: development of a conceptual framework identifying direct, indirect and intangible costs of platelet transfusion, followed by the estimation of the total cost of platelet transfusion in patients with CLD-associated thrombocytopenia before an elective procedure in the United States using the conceptual framework and cost data obtained from a literature search. The cost of the entire care required to raise a patient’s platelet count before the procedure was considered.

Results: The final conceptual framework included the costs of generating the supply of platelets, the platelet transfusion itself, adverse events associated with platelet transfusion and refractoriness to platelet transfusion. When costs were accounted for in all the framework cost categories, the total direct cost of a platelet transfusion in a patient with CLD and associated thrombocytopenia was estimated to be in the range of $5258 to $13,117 (2017?US dollars) in the United States. The largest portion of costs was incurred by the transfusion event itself ($3723 to $4436) and the cost of refractoriness ($874 to $7578), which included the opportunity cost of a delayed procedure and subsequent platelet transfusions with human leukocyte antigen-matched platelets.

Limitations and conclusions: Although we were unable to include all cost components identified in the conceptual framework in our total cost estimate, thus likely underestimating the true total cost, and despite the data gaps and challenges limiting our estimate of the full cost of a platelet transfusion in patients with CLD-associated thrombocytopenia undergoing an elective procedure in the United States, this study outlines a comprehensive conceptual framework for estimating the cost elements of a platelet transfusion in these patients.  相似文献   
995.
Aims: To assess and compare the direct healthcare and non-healthcare costs and government subsidies by body weight and diabetes status.

Methods: The Australian Diabetes, Obesity and Lifestyle study collected health service utilization and health-related expenditure data at the 2011–2012 follow-up surveys. Costing data were available for 4,409 participants. Unit costs for 2016–2017 were used where available or were otherwise inflated to 2016–2017 dollars. Age- and sex-adjusted costs per person were estimated using generalized linear models.

Results: The annual total direct cost ranged from $1,998 per person with normal weight to $2,501 per person with obesity in participants without diabetes. For those with diabetes, total direct costs were $2,353 per person with normal weight, $3,263 per person with overweight, and $3,131 per person with obesity. Additional expenditure as government subsidies ranged from $5,649 per person with normal weight and no diabetes to $8,085 per person with overweight and diabetes. In general, direct costs and government subsidies were higher for overweight and obesity compared to normal weight, regardless of diabetes status, but were more noticeable in the diabetes sub-group. The annual total excess cost compared with normal weight people without diabetes was 26% for obesity alone and 46% for those with obesity and diabetes.

Limitations: Participants included in this study represented a healthier cohort than the Australian population. The relatively small sample of people with both obesity and diabetes prevented a more detailed analysis by obesity class.

Conclusion: Overweight and obesity are associated with increased costs, which are further increased in individuals who also have diabetes. Interventions to prevent overweight and obesity or reduce weight in people who are overweight or obese, and prevent diabetes, should reduce the financial burden.  相似文献   
996.
The prior literature is ambiguous about the effects of stronger intellectual property rights (IPR) on the choice of a multinational firm's mode of entry into foreign markets. However, available indexes of IPR protection exist only at the country level and do not identify interindustry variation in the ability to extract rents through exclusive rights and other factors. The authors introduce this dimension and compute a parameter that reflects the relative length of time that positive profits may be earned in various industries. Estimation results find that strengthening IPR would reduce exporting in all industries in the sample. However, it would raise (reduce) foreign direct investment, relative to licensing, in industries with shorter (longer) rent‐extraction times.  相似文献   
997.
本文认为导致城乡公共产品供给差异的根本原因是地方政府官员根据不同主体能够给予的政治支持做出的理性选择。文章强调了政治支持差异对地方官员行为的影响,并把上级政府、城市居民和农村居民的政治支持纳入一个统一的分析框架,分析了地方官员从不同主体获得的政治支持权重大小顺序,给出了其最优策略的均衡条件。如果要实现基本公共产品均等化目标,则需优化政治支持结构。  相似文献   
998.
Using data aggregated from seven papers that study repeated play in standard ultimatum games with either stranger or absolute stranger matching, we show that the behavior of responders changes with experience. High offers are more likely to be accepted with experience and low offers are more likely to be rejected. At the individual level, there is a negative relationship between the likelihood that a given offer is accepted and the size of the preceding offer. We compare the results with predictions generated by static models of distributional preferences, implicitly dynamic models of preferences with reciprocity, and explicitly dynamic models of adaptive learning. The data is most consistent with models of preferences with reciprocity.  相似文献   
999.
We present a model of a risk-averse exporting firm subject to liquidity constraints. We show that preferences and expectations become important for optimum export and hedging decisions. Only firms that have sufficient financial resources can fully materialize gains from trade.  相似文献   
1000.
When evaluating the risks of future invasions, we often have sparse information on the likelihood that a species will arrive, establish and spread in a new environment, and on the potential impacts should this occur. Conventional risk assessment, therefore, is limited in providing guidance in managing the risk of non-indigenous species (NIS). However, risk management decisions must be made facing these uncertainties to avoid high and irreversible impacts.We develop an integrated ecological economic modeling and deliberative multi-criteria evaluation (DMCE) approach to support group decision-making in risk prioritization, using an example of ten NIS that could potentially impact Australian plant industries. This innovative approach seeks to combine the advantages of dynamic modeling with the benefits of DMCE in assessing and communicating uncertainty. The model unveils the complexity of the socio-ecological system of biological invasion, with a scenario analysis designed to interactively communicate scientific uncertainty to decision-makers. The DMCE provides a structured approach to identifying stakeholders' key concerns in addressing economic, social, and environmental dimensions of NIS risk explicitly. Functioning as a platform for risk communication, the DMCE also offers an opportunity for diverse views to enter the decision-making process and for the negotiation of consensus consensuses.  相似文献   
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