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21.
基于SEA的AGA-SVR节假日客流量预测方法研究 总被引:2,自引:0,他引:2
节假日旅游客流量由于游客在短期内大量集中于同一地点、不同节假日休假时间长短、所处季节等不同,呈现复杂非线性特征和明显季节性特点.本文提出一种基于季节指数调整(Seasonal Exponential Adjustment,SEA)的自适应遗传算法(Adaptive Genetic Algorithm,AGA)-支持向量回归 (Support Vector Regression,SVR)预测模型,即基于SEA的AGA-SVR模型,并用国内著名5A级风景区黄山2008~2012年节假日客流量数据对模型进行验证.研究结果表明,基于SEA的AGA-SVR预测模型能够准确处理节假日旅游客流量预测中的非线性和季节性问题,较AGA-SVR和GA-SVR等方法具有更高的预测精度,在旅游预测领域应用前景广阔. 相似文献
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Anne Bitsch Marit Elisabeth Klemetsen 《Gender, place and culture : a journal of feminist geography》2017,24(2):174-188
This article maps and discusses the legal processing of rape cases in Norwegian appellate courts. Drawing on data from a multivariate regression analysis and a qualitative frame analysis, we examine the significance of space, accuser-convict prior relationship, the social context, accuser-convict marital relationship status, and convict racial background for grading of sentences in rape cases. The data-set consists of 176 rape cases that were processed in 2011 and 2012. Excluding acquittals and controlling for the application of relevant legal provisions, we find that sentences are reduced by 30% if the rape occurs in a private space as opposed to a public space. If the rape occurs at a party or is committed by a perpetrator who is a member of a racial majority, we find that sentences are reduced by 20%. A prior relationship between the victim and the perpetrator reduces sentencing by 18%. Results regarding victims of marital rape are inconclusive. The study concludes that sentencing is stratified according to the public/private divide, prior relationship, social context and race. Despite progress made on behalf of victims of domestic violence and a gradual implementation of stricter sentencing in line with legislative intentions, the legal processing of rape cases is permeated by race and gender discrimination. 相似文献
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This paper examines whether access to the capital market of convertible and nonconvertible bonds affects total factor productivity (TFP) for the population of Italian joint stock manufacturing companies, based in highly segmented local financial markets, between 2007 and 2017. The hypothesis, well grounded in the literature, is that long-term capital favors investment in intangibles and other risky assets necessary for productivity growth. To identify this effect, we exploit the exogenous shock of the Italian banking deregulation of the mid-1990s as an instrument for firm-level access to capital, interacted with distance from logistic networks. These reforms changed the distribution of the type of branches at the local level, increasing the share of joint stock banks, which have high connections to international capital markets. This geographical reallocation of banking activities ultimately affected firms' financial structure, favouring their access to capital, even when based in peripheral financial areas. Firms which issued instruments of market debt achieved higher levels of productivity and a higher probability to reach top percentiles of productivity distribution. 相似文献
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Ping Yu Fan Kwok Pan Chun Ana Mijic Mou Leong Tan Wei Zhai Omer Yetemen 《Geographical analysis》2024,56(2):284-302
While the land use-street network nexus is well acknowledged, evidence for the one-way impacts of land-use patterns on street accessibility is still inadequate. The measurements of land-use patterns and street accessibility lack systematic knowledge. Their empirical correlations also lack geographical variability, constraining site-specific land-use practices. Therefore, this study overcame the aforementioned limitations by examining the two-level spatial models to formulate accessibility-oriented land plans, using a well-developed Chinese city as an example. Firstly, two landscape metrics—Euclidean Nearest-Neighbor Distance (ENN) and Similarity Index (SIMI)—were used to quantify the intra- and inter-land-use configurations, respectively. Both city-level and local accessibility were measured using spatial design network analysis. Performing both ordinary least squares (OLS) and geographically weighted regression (GWR) models, results identified the statistically significant effects of inter-land-use patterns on two-level street accessibility. An exception was that land-use configurations within residential and industrial regions were irrelevant to street accessibility. We also found GWR was a better-fitting model than OLS when estimating locally-varied accessibility, suggesting hierarchical multiscale land-use planning. Overall, locally heterogeneous evidence in this study can substantialize land use-street network interactions and support the decision-making and implementation of place-specific accessibility-oriented land use. 相似文献
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Harriet R. Huber Jeffrey C. Jorgensen Virginia L. Butler Greg Baker Rebecca Stevens 《Journal of archaeological science》2011
Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (Oncorhynchus keta), coho (Oncorhynchus kisutch), pink (Oncorhynchus gorbuscha), and sockeye salmon (Oncorhynchus nerka) and cutthroat (Oncorhynchus clarki clarki) and steelhead trout (Oncorhynchus mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000–3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A. 相似文献
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We investigate the spatial extent of agglomeration economies across the wage earnings distribution using economic mass (total employment) in four distance bands around each individual’s establishment in a quantile regression framework. We control for observable and unobservable individual and establishment characteristics. Remaining endogeneity in the model is assessed with a set of instrumental variables. Results indicate a positive effect of economic mass on wage earnings up to 25 km away from the establishment. The spatial extent of agglomeration economies is similar across the wage earnings distribution. However, increases in economic mass shift the wage earnings distribution in a nonsymmetric way. 相似文献
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Kalle Emil Holst Hansen 《European Planning Studies》2016,24(5):904-925
The recent financial and economic crisis had substantial but spatially differentiated impacts on growth. However, there is still a lot left to be understood about the local aspects of the crisis. One of these aspects is its socio-economic consequences. This paper investigates local socio-economic change to Danish towns from 2008 to 2013, with a focus on the impact of local labour market (LLM) structures on change. Socio-economic change in towns is measured both directly as mean income and employment growth, and indirectly as population and human capital growth. The paper relies on micro-data and uses robust regression to generate results. Several findings are presented, but the two main conclusions are: first, the LLM structures of towns still influence local socio-economic development; and, second, towns experience better socio-economic development if they are in close proximity to a larger labour market and/or have a large ratio of commuters in the working population. 相似文献
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Eric Jenner 《政策研究杂志》2012,40(2):274-301
Who and what influences the issues that policymakers attend to is central to the question of how power is exercised in politics. This study builds upon research by Soroka that proposes an expanded model of agenda setting as a means to examine how the media influences issue salience for the public and policymakers. It expands on Soroka's model by investigating the hypothesis that photographic attention to environmental issues in the news media influences issue salience for the mass public and governmental decision makers. There is little research that substantiates the idea, but it is widely believed that photographs have influence on the policy agenda. I use a dynamic, multidirectional model to estimate whether the volume of news photographs, in addition to news stories, influences issue salience among the mass public and policymakers. Data are longitudinal and measures of attention are operationalized as the number of congressional committee meetings, concern for the environment as a “most important problem” in public opinion polls, environmental news stories in The New York Times, and environmental news photographs in Time magazine. Results suggest that photographic attention does influence environmental policy agenda dynamics in some counterintuitive ways that are distinct from the effects of the news stories. While news stories appear to increase public attention toward the environment, they have little influence on policymaker attention. News photographs, on the other hand, appear to drive congressional committee attention but elicit an ambivalent public response. 相似文献
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《Asian Population Studies》2013,9(2):172-190
Using data from the third National Family Health Survey (NFHS-3) on currently married fecund women who have had at least one birth during 2001–2002 and Cox-proportional hazard models, this study examines the less researched association between women's autonomy and birth-to-conception intervals in India. It also examines whether women's autonomy mediates or moderates the relationship between education and birth-to-conception interval. Our results indicate that after adjusting for demographic and socioeconomic factors, women's autonomy was a significant predictor of birth-to-conception intervals, with higher autonomy positively associated with larger birth-to-conception intervals. Education of women was also independently associated with longer birth-to-conception intervals. However, this study did not provide any support to the general perception that women's autonomy mediates the association between women's education and birth-to-conception interval. Women's autonomy rather than being a mediator acted as a moderator in this association. Policy measures to increase the spacing between births should emphasise not only improving the education of women but also their autonomy. 相似文献