山西省农牧交错区农户饲草种植意愿及影响因素分析基于Logistic 模型和两县区的调查

目的 在我国“粮改饲”背景下，山西省农牧交错区农户是否会改变传统作物而选择种植饲草作物的行为决策会受到诸多因素的影响，文章试图从影响农户饲草种植意愿因素的角度入手，探究增强农户饲草种植积极性的对策和措施。方法 该文以山西省朔州市右玉县和平鲁区为例，基于两县（区）232个样本农户的调查数据，采用Logistic回归模型对农户种植饲草意愿的影响因素进行了实证分析。结果 在所有影响农户饲草种植意愿的因素中，关键性因素是农户的受教育水平、农户对风险的偏好、生产经营的形式、种植饲草的收入、是否受到相应的技术指导、饲草的销售情况、农户对饲草价格的满意度以及对相关政策的知晓度。结论 该文认为应重视有创新精神的新型职业农民的培育；通过多种形式的土地流转，实现土地的适度规模经营，获得规模收益；重视合作社的带动和引导作用，增加饲草种植的组织化程度，降低市场风险和交易成本，提高农户的收入；做好市场调查和预测，以市场倒逼生产，实现饲草市场供需的有效衔接；多渠道加大宣传力度提高农户对政策的知晓度；以此提高农户种植饲草的积极性、促进“粮改饲”政策的顺利实施，实现“粮草兼顾、草畜平衡、农牧结合、循环发展” 的目标。     

高技术产业军民共生模式与发展路径研究

高技术产业是国家军民融合发展的核心领域，构建完善有效的军民生态系统是助力军民融合有序发展、激发军民互动活力的基础。基于共生理论与Logistic增长理论，设计高技术产业军民共生系统框架，构建高技术产业军民共生演化方程。选取雷达及其配套设备制造业等典型产业，对其发展趋势进行拟合，并模拟和分析高技术产业军民共生的各类模式及参数。结果表明，1995—2019年，高技术产业主营业务收入与我国经济发展趋势总体协调，推进高技术产业军民共生发展需要激发新的增长活力。在高技术产业发展中，互惠共生是高技术产业军民共生模式生成新能量的主要模式，提高军民共生系数、扩大产业规模容量是提升军民共生能量层级的重要路径。在此基础上，从建设互惠共生交流机制、建设双向能量流动机制、优化互惠共生界面、扩大高技术产业容量、推动产业链协同5个方面凝炼推动高技术产业军民共生发展的对策建议。     

Forecasting electricity prices using bid data

Market liberalization and the expansion of variable renewable energy sources in power systems have made the dynamics of electricity prices more uncertain, leading them to show high volatility with sudden, unexpected price spikes. Thus, developing more accurate price modeling and forecasting techniques is a challenge for all market participants and regulatory authorities. This paper proposes a forecasting approach based on using auction data to fit supply and demand electricity curves. More specifically, we fit linear (LinX-Model) and logistic (LogX-Model) curves to historical sale and purchase bidding data from the Iberian electricity market to estimate structural parameters from 2015 to 2019. Then we use time series models on structural parameters to predict day-ahead prices. Our results provide a solid framework for forecasting electricity prices by capturing the structural characteristics of markets.     

Predicting and explaining absenteeism risk in hospital patients before and during COVID-19

In order to address one of the most challenging problems in hospital management – patients’ absenteeism without prior notice – this study analyses the risk factors associated with this event. To this end, through real data from a hospital located in the North of Portugal, a prediction model previously validated in the literature is used to infer absenteeism risk factors, and an explainable model is proposed, based on a modified CART algorithm. The latter intends to generate a human-interpretable explanation for patient absenteeism, and its implementation is described in detail. Furthermore, given the significant impact, the COVID-19 pandemic had on hospital management, a comparison between patients’ profiles upon absenteeism before and during the COVID-19 pandemic situation is performed. Results obtained differ between hospital specialities and time periods meaning that patient profiles on absenteeism change during pandemic periods and within specialities.     

西部地区农村流动人口土地流转行为的决策逻辑基于推拉理论视角

目的 分析农村流动人口土地流转行为的决策逻辑，对于促进土地流转、提高土地利用率、加速农业现代化、加快流动人口市民化、推动城乡一体化具有重要意义。方法 文章基于推拉理论视角，利用2017年中国流动人口动态监测调查数据，运用Logistic模型并综合实证调研，分析城乡融合发展背景下西部地区农村流动人口土地流转行为的决策因子及决策逻辑。结果 （1）西部地区农村流动人口土地流转比例偏低，仅30.6%的农户发生土地流转行为。未发生土地流转的农户中，将土地闲置或种植林木的比例达21.1%，土地抛荒、非粮化问题较为突出。（2）西部地区农村流动人口兼具“农民”和“市民”双重身份特征，其土地流转行为决策逻辑契合推拉理论，受个人自身特征、流动范围以及流出地、流入地特征“二维四要素”影响。（3）男性、年迈、重视老家风俗习惯、流动空间跨度大、在流出地存在家人照料问题、在流入地面临歧视或存在买房问题的农户，土地流转意愿偏低，而在流入地拥有高收入的农户，土地流转意愿则较高。结论 在诸多决策因子的影响下，农户遵循“乡土情怀维系、基本生存保障和流转风险规避”决策逻辑，对于离土离乡卷入城市化浪潮的农户而言，土地财产功能弱化，情感功能、保障功能凸显。     

Unleashing the potential of online learning in Spain: An econometric analysis

Online learning and training continue gaining momentum worldwide resulting in the reduction of the traditional form of face-to-face education with its temporal and spatial limitations. Online education improves access to education and training, as witnessed during the Covid-19 pandemic. This article focuses on online education adoption in Spain. A representative survey on ICT use in households conducted annually by the Spanish National Institute of Statistics is used to construct a panel database for the years 2008–2020. The first objective is to provide an econometric model for adopting online education using this panel data. Next is to measure the effects of relevant observable individual socioeconomic variables on adoption. A Heckman selection model allows for estimating the impact of gender, age, education, digital skills, habitat, and income. The article also measures the effects of Covid-19 in 2020 on different population groups. The drivers and impediments have the expected signs and plausible sizes. The paper concludes with policy recommendations and suggestions for further research.     

门票免费模式下公众参观科技馆意愿的实证研究

以江西科技馆为例,运用多元有序Logistic回归模型实证分析了公众个人特征等六类因素对公众在门票免费模式下参观科技馆意愿的影响。研究表明,公众参观科技馆具有较强的目的性,并且公众的年龄、受教育程度、展品布局、展品质量、展厅环境舒适度、参观方便状况、场馆投诉处理情况以及场馆整体信誉度对公众在门票免费模式下参观科技馆具有显著影响。对此,本文提出了开发多样化个性服务、创建良好的场馆环境以及努力提升场馆形象等措施。