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111.
We study the factors influencing the percentage of organic and fair trade certified coffee sold through a cooperative by growers of five cooperatives in Mexico. The percentage of coffee sold through the cooperative was used as a proxy of growers’ engagement with a cooperative. Using factor analysis and a fractional probit regression, we evaluated the proposition that the level of engagement can be explained by transaction cost economics, social norms and connections, and farmer and farm business characteristics. We found that farm size, uncertainty regarding cooperative time of payment to the members and cooperative commitment on price to be paid negatively influence the level of engagement. In contrast, asset specificity, relational commitment, and price have a positive impact on engagement. Our results may help cooperatives and policy makers to build strategies aiming to increase this level of engagement. This is relevant because lower grower engagement has been found to be positively correlated with weak performing cooperatives.  相似文献   
112.
Local festivals may leverage local specialties and various historical, cultural, and artistic resources throughout their respective regions to attract tourists, inducing positive economic impacts. In this study, this paper is a first attempt to analyze the relative efficiency of local festival tourism by using parametric and non-parametric approaches with the data from local festivals held in Korea from 2015 to 2018. We also deal with the efficiency determinants of each typology of festivals by employing a truncated regression with double bootstrapping. Results showed that the leading sources of inefficiency were primarily embedded in pure technology inefficiency, while the principal operational drivers posed different effects depending on the typology of festivals. These insights have important practical implications for the local festival organizing committees and operators in Korea and are helpful in developing tailored operational strategies to maximize the efficiency among different typologies of festivals.  相似文献   
113.
利用辐射源目标的频移动态特征进行盲分选时,针对已有的分选方法不能很好解决非合作接收数据非周期、间断、交叠的问题,提出了一种改进的逻辑回归分选算法,将信号分选转化为轨迹分类的问题来处理。首先,借鉴多目标航迹起始模型中的M/N逻辑法的框架,设计新的数据关联门限,以建立目标起始曲线;其次,采用最小二乘拟合方法替代卡尔曼滤波,设计新的外推规则,建立载频变化预测曲线;分析新的接收数据与预测曲线的关联性,不断迭代回归或形成新的分支,最后获得目标分选结果。仿真与实测试验表明,利用逻辑回归分选算法,对不同运动目标搭载的同频辐射源可进行自动分选,4个仿真目标与2个真实目标的分选正确率达到100%。同时,该方法拓展了辐射源目标盲分选中的动态频移特征应用,为辐射源个体识别提供了新的支持。  相似文献   
114.
Due to the high complexity and strong nonlinearity nature of foreign exchange rates, how to forecast foreign exchange rate accurately is regarded as a challenging research topic. Therefore, developing highly accurate forecasting method is of great significance to investors and policy makers. A new multiscale decomposition ensemble approach to forecast foreign exchange rates is proposed in this paper. In the approach, the variational mode decomposition (VMD) method is utilized to divide foreign exchange rates into a finite number of subcomponents; the support vector neural network (SVNN) technique is used to model and forecast each subcomponent respectively; another SVNN technique is utilized to integrate the forecasting results of each subcomponent to generate the final forecast results. To verify the superiority of the proposed approach, four major exchange rates were chosen for model comparison and evaluation. The experimental results indicate that our proposed VMD-SVNN-SVNN multiscale decomposition ensemble approach outperforms some other benchmarks in terms of forecasting accuracy and statistical tests. This demonstrates that our proposed VMD-SVNN-SVNN multiscale decomposition ensemble approach is promising for forecasting foreign exchange rates.  相似文献   
115.
研究目的:确定住宅用地出让溢价率水平与宗地规模之间的关系,比较不同规模和区位城市中这一关系的差异。研究方法:理论分析,面板数据分析。研究结果:总体上宗地规模对土地溢价率的影响呈现"倒U"型变化关系,不同规模和区位城市中这一关系有差异。人口介于500万~1 000万之间的特大城市中土地溢价水平受宗地规模的影响较为强烈,东部和中部城市中宗地规模大小对土地溢价水平影响显著,西部城市不显著。研究结论:地方政府在总量既定条件下调整宗地投放规模可在一定程度上调控土地溢价率。  相似文献   
116.
对我国16家上市银行进行的实证检验表明:3个月同业拆借利率与银行信用风险显著正相关,人民币5年期基准存款利率与银行信用风险的关系不确定,人民币1年期基准存款利率与银行信用风险显著正相关,贷款利息收入占贷款比例与银行信用风险显著负相关。  相似文献   
117.
Research in economic geography has paid increasing attention to regional innovation systems (RISs) as a potential vehicle for growth and development. Yet despite an increasing amount of research studying RISs in particular and economic regions in general, we have limited knowledge about their influence on entrepreneurs and entrepreneurship. We respond to this knowledge gap and study if entrepreneurs’ localization in thick vs. thin RISs affects their innovativeness and growth ambitions. Thick RISs are predominately urbanized spaces that include organizations of higher-level education, R&D intensive milieus, and an ample industry sector, while thin RISs to a lesser degree encompass these features. Empirically, we analyse 870–917 entrepreneurial firms in Agder of Southern Norway. Based on trade and labour markets, as defined by the EU’s classification of local administrative units (LAU1), we identify two thick and six thin RISs in Agder. Econometric analyses show that entrepreneurs located in thick RISs are more innovative than entrepreneurs located in thin RISs, but there are no significant differences concerning entrepreneurs’ growth ambitions. In light of our findings, we discuss the potential agency role played by entrepreneurial firms at a micro level on path dependent features of RISs at a macro level.  相似文献   
118.
模拟土地利用空间格局分布规律对合理利用土地资源、制定土地利用规划、协调土地与经济、环境的关系具有十分重要的意义。土地利用格局存在空间异质性,对比不同地区格局特征规律对加深土地利用格局的认识具有重要意义。以邻接的湖北省宣恩县和咸丰县为研究对象,通过对比基于局地因子、自相关因子和邻域因子的3种Logistic模型的模拟参数的一致性和异质性来对比研究两地的格局分布规律。实验与分析结果表明,宣恩县和咸丰县的土地利用格局特征存在共同的驱动因子和聚集效应,具有共性;不同模型的模拟结果表明驱动因子在作用方向,大小方面存在差异,邻域因子在邻域尺度上表现出不同特征。研究结果对加深理解不同地区的土地利用分布格局特征的差异性,促进区域土地利用的规划、土地资源的合理开发与可持续发展战略的顺利实施具有一定的参考价值。  相似文献   
119.
陕北黄陵县农户生计资本评价及其生计策略研究   总被引:1,自引:0,他引:1  
[目的]选取受退耕还林、封山禁牧等生态政策影响较大的陕北农户为研究对象,分析农户生计资本与生计策略之间的作用关系。[方法]基于可持续生计分析框架,采用Logistic回归模型,对17个行政村335户样本农户数据进行分析。[结果](1)研究区农户的人力资本整体得分最高,社会资本居次,物质资本中等偏下,自然资本和金融资本处于低水平;(2)农户生计分化明显,典型的纯农户很少,农户生计策略主要为兼农型和低水平非农型;(3)回归分析表明,人力资本指数高的农户倾向于外地兼农,物质资本和社会资本指数高的农户倾向于当地兼农,家庭年收入、人均教育投入和人情往来3项指标是促进农户向非农型生计策略转变的关键因子。[结论]农户生计策略的选择和转变是建立在自身资本结构上的,其往往向着发挥生计资本优势、规避生计资本短板的方向调整生计策略,进而达到提高整体生计资本水平的目的。人力资本优势主导下的黄陵县,加之沟壑区农地资源空间配置的破碎性与复杂性,外地兼农型生计策略将仍是该地区农户近期内的主要生计抉择。  相似文献   
120.
Justifying ridge regression from a geometrical perspective is one of the main contributions of this paper. To the best of our knowledge, this question has not been treated previously. This paper shows that ridge regression is a particular case of raising procedures that provide greater flexibility by transforming the matrix X associated with the model. Thus, raising procedures, based on a geometrical idea of the vectorial space associated with the columns of matrix X , lead naturally to ridge regression and justify the presence of the well-known constant k on the main diagonal of matrix X X . This paper also analyses and compares different alternatives to raising with respect to collinearity mitigation. The results are illustrated with an empirical application.  相似文献   
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