数字金融对农户气候适应性行为的影响

气候适应性技术采用率低下已成为制约农业可持续发展的重要因素,数字金融可能影响农户的气候适应性行为。基于河南、陕西、山西三省1 384份农户微观调查数据,运用内生转换回归模型构建反事实分析框架,实证分析数字金融使用对农户气候适应性行为的影响效应及其作用机制。研究发现:使用数字金融能显著促进农户气候适应性技术采纳行为,具体表现为在反事实假设下,使用数字金融的农户若未使用其气候适应性技术采纳程度将下降;未使用数字金融的农户如果使用了,其气候适应性技术采纳程度将上升。机制分析表明,数字金融能够提高借贷易得性与信息易得性,进而促进农户采纳气候适应性行为,农户对于金融包容性的认知能够正向增强数字金融对农户气候适应性行为的影响效应。异质性分析表明,数字金融使用对于资本型适应性行为影响的边际效应最大,在反事实假设下也表现为数字金融使用对农户资本型适应性行为提升效果最强;数字金融对农业收入占家庭收入比率较高、接受过培训的农户采纳气候适应性技术促进效应更高。     

面向人与自然和谐共生的环境党内法规的治理逻辑

建设面向人与自然和谐共生的中国式现代化,中国式法治化是必然要求,其中环境法治不可或缺。中国式的环境法治必然要重视党内法规的特殊法治和治理功能。可从着力发挥党内法规在环境法治中的特殊作用、统筹推进环境综合治理的规范功能、推动构建人类环境命运共同体的制度文明三方面,揭示出环境党内法规所秉持环境系统观、环境效能观、环境文明观的政理法理。环境党内法规有广义和狭义之分,环境党内法规所承载上述治理逻辑的规范样态,不仅包括符合《中国共产党党内法规制定条例》严格形式要件的狭义党内法规,也包括引领环境法治发展的环境政策、起到监督保障等作用的党内环境规范性文件。从环境党内法规的政治功能和规范效力来讲,将以决议、决定、意见、通知等为主要载体的环境政策视为广义的环境党内法规,符合新形势下环境党内法规体系构筑的核心要义。从目前党内法规体系的构成情况看,起到监督保障作用的党内环境规范性文件成为了主力军,但其数量庞杂又单线作战的实践困境使其亟需完善以形成治理合力。因此,应进一步探讨党的环境政策和党内环境规范性文件向狭义党内法规的有机转化,使狭义的环境党内法规成为环境党内法规体系的主体部分。广义视阈下的环境党内法规,在面向人与自然和谐共生的现代化中发挥着规范、治理与重塑的制度功能。环境党内法规通过将党的不成文的环境文明提炼转化为具有约束力的制度形态,从而使其获得长远的效能力和长期的执行力。环境党内法规通过为生态文明建设提供制度赋能,从而全面发挥其环境治理的政治效能、预防效能和发展效能。环境党内法规以党的领导为本质特征的政治结构为环境文明奠基、以人民为中心的人本理念为环境文明铸魂、以党规国法共治为保障的外部制度为环境文明塑形,使其实质上具备了打造人类环境文明新形态的重塑功能。需要注意的是,完备的环境党内法规体系对上述功能的系统发挥尤为重要,因此,面向人与自然和谐共生的环境党内法规,还有待进一步体系化完善。     

Factors influencing Soay sheep survival

We present a survival analysis of Soay sheep mark recapture and recovery data. Unlike previous conditional analyses, it is not necessary to assume equality of recovery and recapture probabilities; instead these are estimated by maximum likelihood. Male and female sheep are treated separately, with the higher numbers and survival probabilities of the females resulting in a more complex model than that used for the males. In both cases, however, age and time aspects need to be included and there is a strong indication of a reduction in survival for sheep aged 7 years or more. Time variation in survival is related to the size of the population and selected weather variables, by using logistic regression. The size of the population significantly affects the survival probabilities of male and female lambs, and of female sheep aged 7 or more years. March rainfall and a measure of the North Atlantic oscillation are found to influence survival significantly for all age groups considered, for both males and females. Either of these weather variables can be used in a model. Several phenotypic and genotypic individual covariates are also fitted. The only covariate which is found to influence survival significantly is the type of horn of first-year female sheep. There is a substantial variation in the recovery probabilities over time, reflecting in part the increased effort when a population crash was expected. The goodness of fit of the model is checked by using graphical procedures.     

Bootstrapping regression models with BLUS residuals

To bootstrap a regression problem, pairs of response and explanatory variables or residuals can be resam‐pled, according to whether we believe that the explanatory variables are random or fixed. In the latter case, different residuals have been proposed in the literature, including the ordinary residuals (Efron 1979), standardized residuals (Bickel & Freedman 1983) and Studentized residuals (Weber 1984). Freedman (1981) has shown that the bootstrap from ordinary residuals is asymptotically valid when the number of cases increases and the number of variables is fixed. Bickel & Freedman (1983) have shown the asymptotic validity for ordinary residuals when the number of variables and the number of cases both increase, provided that the ratio of the two converges to zero at an appropriate rate. In this paper, the authors introduce the use of BLUS (Best Linear Unbiased with Scalar covariance matrix) residuals in bootstrapping regression models. The main advantage of the BLUS residuals, introduced in Theil (1965), is that they are uncorrelated. The main disadvantage is that only n —p residuals can be computed for a regression problem with n cases and p variables. The asymptotic results of Freedman (1981) and Bickel & Freedman (1983) for the ordinary (and standardized) residuals are generalized to the BLUS residuals. A small simulation study shows that even though only n — p residuals are available, in small samples bootstrapping BLUS residuals can be as good as, and sometimes better than, bootstrapping from standardized or Studentized residuals.     

Differential equation models for statistical functions

Differential equations have been used in statistics to define functions such as probability densities. But the idea of using differential equation formulations of stochastic models has a much wider scope. The author gives several examples, including simultaneous estimation of a regression model and residual density, monotone smoothing, specification of a link function, differential equation models of data, and smoothing over complicated multidimensional domains. This paper aims to stimulate interest in this approach to functional estimation problems, rather than provide carefully worked out methods.     

资源型工矿业城市的再就业问题——以唐山市为例

资源型工矿业城市的再就业问题与其他城市相比具有特殊性和解决的紧迫性与困难性。本文以唐山市为例 ,在分析资源型工矿业城市再就业的困境及形成原因的基础上 ,探讨了这类城市再就业难题的解困思路     

远程辅助教学系统的研究

本文讨论了网上远程系统的智能系统模型和实现方法。实现教师和学生的远程交互,对学生学籍进行管理,并有测试功能便于学生自测,可记录学生的平时成绩供教师参考。     

Transformation using ( x + 0.5) to stabilize the variance of populations

Transformation is required to achieve homo-scedasticity when we perform ANOVA to test the effect of factors on population abundance. The effectiveness of transformations decreases when the data contain zeros. Especially, the logarithmic transformation or the Box–Cox transformation is not applicable in such a case. For the logarithmic transformation, 1 is traditionally added to avoid such problems. However, there is no concrete foundation as to why 1 is added rather than other constants, such as 0.5 or 2, although the result of ANOVA is much influenced by the added constant. In this paper, I suggest that 0.5 is preferable to 1 as an added constant, because a discrete distribution defined in {0, 1, 2, . . .} is approximately described by a corresponding continuous distribution defined in (0, ≧) if we add 0.5. Numerical investigation confirms this prediction. Received: October 16, 1998 / Accepted: June 10, 1999     

A new heteroscedastic regression to analyze mass loss of wood in civil construction in Brazil

A heteroscedastic regression based on the odd log-logistic Marshall–Olkin normal (OLLMON) distribution is defined by extending previous models. Some structural properties of this distribution are presented. The estimation of the parameters is addressed by maximum likelihood. For different parameter settings, sample sizes and some scenarios, various simulations investigate the performance of the heteroscedastic OLLMON regression. We use residual analysis to detect influential observations and to check the model assumptions. The new regression explains the mass loss of different wood species in civil construction in Brazil.     

文化视野下的《聊斋志异》科第观

从文化的角度,即从个体科场失意的心理与士子普遍的科举心态的层面上,从选贤用能与个体的怀才不遇层面上,从儒家传统文化的传承与八股取士的层面上,从公平竞争的科举选拔制度与试官腐败的层面上,辩证、历史与客观地审视蒲松龄的作品《聊斋志异》所表现出的科第观,重新解读《聊斋志异》的科第观所带给我们的启示。