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71.
The Mixed Logit model: The state of practice 总被引:7,自引:0,他引:7
The mixed logit model is considered to be the most promising state of the art discrete choice model currently available. Increasingly researchers and practitioners are estimating mixed logit models of various degrees of sophistication with mixtures of revealed preference and stated choice data. It is timely to review progress in model estimation since the learning curve is steep and the unwary are likely to fall into a chasm if not careful. These chasms are very deep indeed given the complexity of the mixed logit model. Although the theory is relatively clear, estimation and data issues are far from clear. Indeed there is a great deal of potential mis-inference consequent on trying to extract increased behavioural realism from data that are often not able to comply with the demands of mixed logit models. Possibly for the first time we now have an estimation method that requires extremely high quality data if the analyst wishes to take advantage of the extended behavioural capabilities of such models. This paper focuses on the new opportunities offered by mixed logit models and some issues to be aware of to avoid misuse of such advanced discrete choice methods by the practitioner. 相似文献
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掺纤维水泥稳定碎石基层材料配合比研究 总被引:3,自引:0,他引:3
水泥稳定碎石基层材料由于刚性大,容易收缩开裂,导致沥青混凝土面层反射裂缝.一般地,水泥稳定碎石基层材料收缩受级配和外加剂等因素的影响,文章在固定级配的基础上,通过在水泥稳定碎石基层材料中掺加适量的纤维,以减少基层材料的刚性,增大其抗裂能力.鉴于掺纤维水泥稳定碎石基层材料路用性能影响因素多,文章采用均匀设计方法安排试验,并用SPSS统计软件对试验结果进行回归分析,确定了影响掺纤维水泥稳定碎石基层路用性能的主要因素和最佳配合比.试验结果表明,掺纤维水泥稳定碎石具有良好的柔韧性能和较小的收缩系数. 相似文献
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This paper presents a dynamic network‐based approach for short‐term air traffic flow prediction in en route airspace. A dynamic network characterizing both the topological structure of airspace and the dynamics of air traffic flow is developed, based on which the continuity equation in fluid mechanics is adopted to describe the continuous behaviour of the en route traffic. Building on the network‐based continuity equation, the space division concept in cell transmission model is introduced to discretize the proposed model both in space and time. The model parameters are sequentially updated based on the statistical properties of the recent radar data and the new predicting results. The proposed method is applied to a real data set from Shanghai Area Control Center for the short‐term air traffic flow prediction both at flight path and en route sector level. The analysis of the case study shows that the developed method can characterize well the dynamics of the en route traffic flow, thereby providing satisfactory prediction results with appropriate uncertainty limits. The mean relative prediction errors are less than 0.10 and 0.14, and the absolute errors fall in the range of 0 to 1 and 0 to 3 in more than 95% time intervals respectively, for the flight path and en route sector level. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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全并联AT供电牵引网短路故障分析 总被引:5,自引:8,他引:5
针对全并联AT供电牵引网的3种短路故障,结合当量等值电路进行了理论分析,得出了各种不同故障下的电流分布情况。通过对电流分布分析,提出了适合全并联AT供电牵引网的故障测距方法,并给出了3种情况下的线路测量阻抗。 相似文献
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SMA施工技术在城市道路维修中的应用 总被引:1,自引:0,他引:1
该文介绍了沧州市解放西路工程的概况,并介绍了橡胶沥青封层、SMA面层施工过程,以及SMA在城市道路维修中的应用。 相似文献