关键词： Canada   cost and cost analysis   doulas   models   economic  

摘要： Introduction: Spending on care in childbirth represents a sizable portion of health care budgets. This has engendered a growing interest in potential clinical tools that could be used to improve patient experience and population health at a lower cost. A possible such tool is continuous support in labor from a trained doula, as doula care can decrease the likelihood of cesarean birth, epidural analgesia, and assisted vaginal birth. In addition, there is some emerging evidence suggesting that involving doulas in prenatal care can reduce rates of preterm birth. Methods: We used data on the associations between doula care and these outcomes derived from a Cochrane review of continuous labor support to create an economic model of universal doula support in the Canadian province of British Columbia. These relative risks were used to estimate procedure reductions and the resulting cost savings using data on the number of relevant procedures performed from Perinatal Services BC coupled with cost information from the Canadian Institutes for Health Information. Results: For the calendar year 2013, we estimated savings inCanadian dollars (CaD) ofCaD$ 10,428,171 (95% confidence interval [ CI], $ 5,430,650$ 14,434,740) if every low-risk birth were attended by a professional doula, not including the cost of the doula's services. Including reduction in preterm birth increases total savings to CaD $ 17,847,370 (95% CI, $ 6,772,341-$ 27,054,610). A professional doula providing labor support would yield an estimated savings of CaD $ 269.55 (95% CI, $ 141.70-$ 374.14) per low-risk birth or CaD $ 418.67 (95% CI, $ 158.87-$ 634.65) if including reductions in preterm birth. Any cost savings disappear at a doula reimbursement rate above CaD $ 418.67 per birth. Discussion: There is potential to reduce health care costs while improving patient experience and population health by providing universal doula coverage. However, our results suggest that reimbursement rates for doulas would have

关键词： Inventory routing   Industrial gas distribution   Mathematical modelling   Inventory control   Mixed integer programming   Economic model predictive control  

摘要： The paper proposes an economic model predictive control (EMPC) strategy for the inventory routing problem under demand uncertainty. The strategy is illustrated using an application on industrial gas distribution systems, where the product is transported to customers in small tanks and the inventory levels at the customers' sites are monitored and controlled by the supplier following a vendor managed inventory approach. The objective is to produce balanced decisions for the joint routing and the inventory control problem over the planning horizon with respect to the decision maker's perspective against stock-out risk. The proposed EMPC strategy makes use of a mixed integer mathematical programming optimization model that describes the deterministic inventory routing problem with simultaneous pickups and deliveries over a specific planning horizon. A time series decomposition forecasting model is used for predicting future demand and an exact linearization of the quadratic term of the objective function guarantees optimality of the solutions. The proposed methodology is illustrated using two examples featuring a single distribution centre, and three customers with simple and complex demand profiles. It is shown that EMPC offers a useful tool for producing balanced decisions between transportation and inventory costs and tracking of the safety inventory levels.

关键词： decision making   health economics methods   statistics   validation  

摘要： Background: The validation of health economic (HE) model outcomes against empirical data is of key importance. Although statistical testing seems applicable, guidelines for the validation of HE models lack guidance on statistical validation, and actual validation efforts often present subjective judgment of graphs and point estimates. Objectives: To discuss the applicability of existing validation techniques and to present a new method for quantifying the degrees of validity statistically, which is useful for decision makers. Methods: A new Bayesian method is proposed to determine how well HE model outcomes compare with empirical data. Validity is based on a preestablished accuracy interval in which the model outcomes should fall. The method uses the outcomes of a probabilistic sensitivity analysis and results in a posterior distribution around the probability that HE model outcomes can be regarded as valid. Results: We use a published diabetes model (Modelling Integrated Care for Diabetes based on Observational data) to validate the outcome "number of patients who are on dialysis or with end-stage renal disease." Results indicate that a high probability of a valid outcome is associated with relatively wide accuracy intervals. In particular, 25% deviation from the observed outcome implied approximately 60% expected validity. Conclusions: Current practice in HE model validation can be improved by using an alternative method based on assessing whether the model outcomes fit to empirical data at a predefined level of accuracy. This method has the advantage of assessing both model bias and parameter uncertainty and resulting in a quantitative measure of the degree of validity that penalizes models predicting the mean of an outcome correctly but with overly wide credible intervals.

关键词： TV   Economics   Utility theory   Internet   Business   Computational modeling   Predictive models  

摘要： Studying the decisions of 25,646 domain name registrants reveals that behavioral economics models more accurately predict name choice than models based on expected utility theory. These findings have implications for Internet governance, and organizations that measure similarity and competition in domain name registration.

关键词： Predictive control   Reforming   naphtha   Economic Models   dynamic models   procedural model  

摘要： Catalytic naphtha reforming is a crucial process in producing gasoline or aromatic Compounds. The characteristic of two production modes gives rise to different economic optimization and control objectives. In the present work, we design an economic model predictive control (EMPC) with a production mode switching strategy to cope with these problems. First, a rigorous dynamic process model is established;to simulate the naphtha reforming process. Then, we formulate different econornic objective functions and simplify the process model for each production mode, and also enable the EMPC controller to switch the production mode automatically according to empirical equations. Three case studies are presented to test the performance of our proposed control strategy. The results,show that the designed EMPC controller with production mode switching can successfully overcome the economic disturbances and improve the :production profits in different production modes. In addition, it also has a fast response tithe to drive the system to a new economic optimal operating point.

关键词： 交通事故   宏观计量经济模型   科布-道格拉斯生产函数   固定效应   面板数据  

摘要： 从经济发展水平、人口数量、汽车保有量和道路条件等宏观因素入手,分析了我国8个省市不同经济发展条件下,人均GDP与千人汽车保有量、万车死亡人数、十万人口死亡人数和人均道路里程之间的关系,并选取万车死亡人数作为因变量,人均GDP、千人汽车保有量和人均道路里程作为自变量,以科布-道格拉斯生产函数为基础,建立了基于计量经济学的固定效应面板数据模型,并对我国交通事故发生规律进行了模拟分析。结果表明:模型拟合效果较好,相关系数R2为0.957 1,各项因素均表现显著,模型较好地反映了我国2003年之后8省市的交通事故宏观规律。

关键词： 林业经济   空间计量   产出弹性   空间误差模型  

摘要： 基于中国31个省份2015年林业投入产出数据,在考虑省域空间联系因素的情况下,建立空间计量经济模型对中国林业要素产出弹性进行测度。研究结果表明:中国31个省份的林业产出存在显著的空间相关性,与传统的估计方法相比,空间计量模型能够揭示中国省域林业产出的空间相关性,能更准确地测度林业生产要素的产出弹性;在考虑省域空间联系因素之后发现,劳动力投入对林业产出的弹性为0.404,资本投入对林业产出的弹性为0.682,说明资本投入对林业产出的贡献大于林业劳动力投入的贡献。最终提出制定区域林业生产激励政策、建立区域统筹协调发展的林业生产合作机制等政策建议。

关键词： energy management   hybrid vehicles   distributed model predictive control   dual decomposition   auxiliaries  

摘要： In this paper, a real-time distributed economic model predictive control approach for complete vehicle energy management (CVEM) is presented using a receding control horizon in combination with a dual decomposition. The dual decomposition allows the CVEM optimization problem to be solved by solving several smaller optimization problems. The receding horizon control problem is formulated with variable sample intervals, allowing for large prediction horizons with only a limited number of decision variables and constraints in the optimization problem. Furthermore, a novel on/off control concept for the control of the refrigerated semi-trailer, the air supply system and the climate control system is introduced. Simulation results on a low-fidelity vehicle model show that close to optimal fuel reduction performance can be achieved. The fuel reduction for the on/off controlled subsystems strongly depends on the number of switches allowed. By allowing up to 15-times more switches, a fuel reduction of 1.3% can be achieved. The approach is also validated on a high-fidelity vehicle model, for which the road slope is predicted by an e-horizon sensor, leading to a prediction of the propulsion power and engine speed. The prediction algorithm is demonstrated with measured ADASIS information on a public road around Eindhoven, which shows that accurate prediction of the propulsion power and engine speed is feasible when the vehicle follows the most probable path. A fuel reduction of up to 0.63% is achieved for the high-fidelity vehicle model.

关键词： F41   E44   G01   H23  

摘要： This paper contributes to a literature that studies optimal capital control policy in open economy models with pecuniary externalities due to flow collateral constraints. It shows that the optimal policy calls for capital controls to be lowered during booms and to be increased during recessions. These findings are at odds with the conventional view that capital controls should be tightened during expansions to curb capital inflows and relaxed during contractions to discourage capital flight.

关键词： economic impact   EMSI   IMPLAN   regional economic model  

摘要： Economic Modeling Specialist International (EMSI) model is a common economic development research tool that has begun to be utilized for tourism research. Therefore, it is important to examine the differences between the EMSI model and the commonly used Impact Analysis for Planning (IMPLAN) model. The multiplier effects of the default version of EMSI and IMPLAN were compared using data obtained from a visitor expenditure survey of the Jackson Mississippi Mistletoe Marketplace. The results revealed that IMPLAN estimated larger multiplier effects (both type I and type II) than EMSI for the total output and employment (job supports).