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1.
Crispin H. V. Cooper 《International Journal of Sustainable Transportation》2018,12(10):714-724
Betweenness is a measure long used in spatial network analysis (SpNA) to predict flows of pedestrians and vehicles, and more recently in public health research. We improve on this approach with a methodology for combining multiple betweenness computations using cross-validated ridge regression to create wide-scale, high-resolution transport models. This enables computationally efficient calibration of distance decay, agglomeration effects, and multiple trip purposes. Together with minimization of the Geoffrey E. Havers (GEH) statistic commonly used to evaluate transport models, this bridges a gap between SpNA and mainstream transport modeling practice. The methodology is demonstrated using models of bicycle transport, where the higher resolution of the SpNA models compared to mainstream (four-step) models is of particular use. Additional models are developed incorporating heterogeneous user preferences (cyclist aversion to motor traffic). Based on network shape and flow data alone the best model gives reasonable correlation against cyclist flows on individual links, weighted to optimize GEH (r2 = 0.78, GEH = 1.9). As SpNA models use a single step rather than four, and can be based on flow data alone rather than demographics and surveys, the cost of calibration is lower, ensuring suitability for small-scale infrastructure projects as well as large-scale studies. 相似文献
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Shinichi Yamaguchi Kotaro Iyanaga Hirohide Sakaguchi Tatsuo Tanaka 《The Review of Socionetwork Strategies》2017,11(2):95-110
In this paper, we discuss the substitution effects between mobile games and console games. We estimate such effects by a fixed-effect regression with instrumental variables using panel data of about 100,000 observations. The results showed that the substitution effects of playing smart devices on 3DS, Wii, and PSP were recognizable, but did not have significant effects on PS3, and the substitution effects on PSP were very small. Therefore, mobile games had a substitution effect on casual console games, or on console games in which the play situation resembled mobile games. In addition, the substitution effects were at most about 0.1. The substitution effects were small. Our results indicate that mobile games represent the pioneers in the new market of gaming at least during our observation period. But new games and traditional games will coexist for a while. 相似文献
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H. J. van der Heim 《De Economist》1884,33(2):1041-1069
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H. E. Kleijn 《De Economist》1882,31(2):1097-1106
IngezondenRefer. Dep. v. Oorlog. 相似文献
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