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101.
P. N. Pali M. Schut P. Kibwika L. Wairegi M. Yami P. J. A. van Asten 《国际农业可持续发展杂志》2018,16(3):272-285
Agricultural policies in sub-Saharan Africa have paid insufficient attention to sustainable intensification. In Uganda, agricultural productivity has stagnated with aggregate increases in crop production being attributed to expansion of cultivated land area. To enhance sustainable crop intensification, the Ugandan Government collaborated with stakeholders to develop agricultural policies using an evidence-based approach. Previously, evidence-based decision-making tended to focus on the evidence base rather than evidence and its interactions within the broader policy context. We identify opportunities and pitfalls to strengthen science engagement in agricultural policy design by analysing the types of evidence required, and how it was shared and used during policy development. Qualitative tools captured stakeholders' perspectives of agricultural policies and their status in the policy cycle. Subsequent multi-level studies identified crop growth constraints and quantified yield gaps which were used to compute the economic analyses of policy options that subsequently contributed to sub-national program planning. The study identified a need to generate relevant evidence within a short time 'window' to influence policy design, power influence by different stakeholders and quality of stakeholder interaction. Opportunities for evidence integration surfaced at random phases of policy development due to researchers’ ’embededness’ within co-management and coordination structures. 相似文献
102.
103.
Ellis J. Neufeld Robert F. Sidonio Jr M. Chris Runken Kellie Meyer Jeffrey Spears 《Journal of medical economics》2018,21(8):762-769
Background: Inhibitor development to factor VIII (FVIII) hemophilia therapy results in increased complications and substantial economic costs. The SIPPET study, the first randomized controlled trial to compare the immunogenicity of plasma-derived FVIII (pdFVIII)/von Willebrand factor (VWF) and recombinant-DNA-derived FVIII (rFVIII), demonstrated higher inhibitor rates in previously untreated patients (PUPs) treated with rFVIII than in PUPs treated with pdFVIII/VWF.Objective: To quantify the economic impact of treating PUPs with pdFVIII/VWF vs rFVIII.Methods: An Excel-based clinical and economic model was developed from a US healthcare payer perspective and run over a 5-year period. The analysis utilized a cohort approach to model patient treatment and outcomes over a monthly cycle to quantify differences in costs of FVIII, bypassing agents, and hospitalizations for serious bleeds. Rates of high-titer inhibitor development were obtained from the SIPPET study. Patients developing high-titer inhibitors were treated with immune tolerance induction (ITI). Patients who developed low-titer inhibitors and those who did not develop inhibitors continued their usual FVIII treatment. Patients who were successfully treated with ITI returned to FVIII treatment, while unsuccessfully treated patients received bypassing agents. Total costs per treated patient were estimated and a one-way sensitivity analysis was conducted to quantify the impact of parameter uncertainty on the model outcomes.Results: Total cumulative costs per patient over 5 years were $834,621 for pdFVIII/VWF patients and $1,237,163 for rFVIII patients, representing a total saving of $402,542 per patient over the 5-year period, for an average annual saving of $80,508 per patient.Conclusions: Based on data from the SIPPET study, this analysis found that initiating FVIII treatment in severe hemophilia A PUPs with pdFVIII/VWF has the potential to offer substantial cost savings to healthcare payers, amounting to a one-third reduction in costs. 相似文献
104.
Here we consider the record data from the two-parameter of bathtub-shaped distribution. First, we develop simplified forms for the single moments, variances and covariance of records. These distributional properties are quite useful in obtaining the best linear unbiased estimators of the location and scale parameters which can be included in the model. The estimation of the unknown shape parameters and prediction of the future unobserved records based on some observed ones are discussed. Frequentist and Bayesian analyses are adopted for conducting the estimation and prediction problems. The likelihood method, moment based method, bootstrap methods as well as the Bayesian sampling techniques are applied for the inference problems. The point predictors and credible intervals of future record values based on an informative set of records can be developed. Monte Carlo simulations are performed to compare the so developed methods and one real data set is analyzed for illustrative purposes. 相似文献
105.
Roman M. Sheremeta 《Journal of economic surveys》2018,32(3):683-704
Group contests are ubiquitous. Some examples include warfare between countries, competition between political parties, team‐incentives within firms, and rent‐seeking. In order to succeed, members of the same group have incentives to cooperate with each other by expending effort. However, since effort is costly, each member also has an incentive to abstain from expending any effort and instead free ride on the efforts of other members. Contest theory predicts that the intensity of competition between groups and the amount of free riding within groups depend on the group size, sharing rule, group impact function, contest success function, and heterogeneity of players. We review experimental studies testing these theoretical predictions. Most studies find significant over‐expenditure of effort relative to the theory and significant heterogeneity of behavior within and between groups. Also, most studies find support for the comparative statics predictions of the theory (with the exception of the “group size paradox”). Finally, studies show that there are effective mechanisms that can promote within‐group cooperation and conflict resolution mechanisms that can de‐escalate and potentially eliminate between‐group conflict. 相似文献
106.
Without guaranteed compensation, granted by the German Renewable Energy Sources Act (Erneuerbare Energien Gesetz/EEG), biogas plants compete with all other plant types on the market for electrical energy. However, exchange-based electricity products do not currently permit an economically viable operation of biogas plants owing to their cost situation. 相似文献
107.
This article compares the salary structure of tenured and tenure-track faculty across schools within the university systems of North Carolina and New York. Specifically, we establish a positive relationship between school prestige and salary inequality, both overall and within specific academic ranks. This result suggests that the value to teaching is less discipline-specific than the value to research output. Marked differences in the aforementioned statistical linkage across academic ranks also confirm prior speculation that junior faculty salaries are more closely tied to academic value than senior faculty salaries. 相似文献
108.
Luke M. Froeb Russell W. Pittman Charles S. Taragin Steven Tschantz Gregory J. Werden 《Review of Industrial Organization》2018,53(4):637-651
This article describes some of the work of Antitrust Division economists over the past year, with a focus on modeling. It begins by illustrating the mapping from evidence to prediction using tools for assessing the effects of mergers using Bertrand, Cournot, and auction models. It then turns to two hot topics in competition policy: the implications of claims of increasing margins for merger enforcement and the validity of claims of increasing concentration. Finally, it considers how mergers affect prices in bargaining models. 相似文献
109.
Ayman E. Khedr Amira M. Idrees Abd El-Fatah Hegazy Samir El-Shewy 《Enterprise Information Systems》2018,12(2):196-217
This study presents a configurable approach for recommendations which determines the suitable recommendation method for each field based on the characteristics of its data, the method includes determining the suitable technique for selecting a representative sample of the provided data. Then selecting the suitable feature weighting measure to provide a correct weight for each feature based on its effect on the recommendations. Finally, selecting the suitable algorithm to provide the required recommendations. The proposed configurable approach could be applied on different domains. The experiments have revealed that the approach is able to provide recommendations with only 0.89 error rate percentage. 相似文献
110.
Valerien O. Pede Raymond J. G. M. Florax Henri L. F. de Groot Gustavo Barboza 《Economic Notes》2021,50(1)
This paper studies the determinants of technological catch‐up considering spatial and sectoral aggregation of industries. We investigate how geographical and technological proximity to the technology leader impact regional employment growth. We model technological progress by means of a hierarchical process of catch‐up to the technology leader. We also incorporate measures for knowledge spillover effects to test the roles of competition, specialisation, and diversity at the industry level. Empirical results using data at the county level for different economic sectors (2‐dig NAICS) for the United States indicate that human capital plays a crucial role in promoting sectoral employment growth. The association between technological/geographical distance to the technology leader and employment growth varies across sectors. 相似文献