Carbon productivity convergence club and its initial conditions: China's construction industry

A three-stage method is proposed to study the convergence clubs for the dynamic total factor carbon productivity (DCP) and the initial conditions. The first stage is to measure the DCP that reflects the initial difference. The second stage is to identify the convergence club of DCP. The last stage is to examine the initial factors that may affect the formation of the convergence club. Construction industry data from 30 provinces in China's Mainland from 2005 to 2016 were adopted to conduct an empirical study. The empirical results showed that (1) the arithmetic mean value of China’s provincial DCP showed an upward trend and the standard deviation showed an expanding trend.(2) There are five convergence clubs, but 13 provinces failed to converge to any club.(3) The higher the degree of construction industry marketization in 2005, the greater the probability that the provinces belong to a club with higher DCP. To improve the DCP, the effective diffusion of low-carbon construction technologies and the market-oriented reform of state-owned construction companies should be promoted. The three-stage method can also be applied to study different industries in different countries or regions.

Convergence Rate of Empirical Bayes Test for the Parameter of the Truncated-type Distribution Families

In this paper, we construct the empirical B ay es test (EBT) for the parameter of the truncated-type distribution families. It is found that the proposed test is asymptotically optimal. The convergence rate of the EBT is given.

Regional Disparity and Convergence of China's Inbound Tourism Economy

Comprehending regional characteristics and influencing factors of China＇s inbound tourism economy is im- portant to make effective policies that will help inbound tourism develop harmoniously and shrink regional disparity. This paper studied the regional disparity and convergence of China＇s inbound tourism economy during 1996-2008 with the methods of a-convergence, club convergence and r-convergence. The results indicate that 1） inbound tourism receipts per capita （ITRPC） of the whole country, the eastern, central and western regions presented the rapid increasing trend; 2） ITRPC of the whole country was characterized by convergence; 3） the eastern region presented club con- vergence, but the central and western regions did not show this trend; 4） the star-hotel levels and investment in fixed assets for the tourism industry per capita had a same trend to growth rates of ITRPC, promoting inbound tourism de- velopment, and there was no difference among the 31 provinces （municipalities） in the mainland of China; 5） but the proportion of employed persons in the tourism industry accounting for total population and the proportion of the terti- ary industry accounting for GDP had a reversal trend to growth rates of ITRPC, shrinking the provincial disparity in inbound tourism economy, and there were differences between the developed provinces and the developing provinces. Based on these analyses, we put forward some suggestions for the developing provinces to speed up inbound tourism economy.

Seismological evidence for the convergence of crustal stress orientation before large earthquakes

Earthquakes are caused by the failure of faults, driven by tectonic stress build-up in the Earth＇s crust. To study the earthquake preparation process and assess regional earthquake potentials, it is vitally important to understand the crustal stress evolution process and identify its change in pattern associated with the seismogenic process. In this study we investigate the focal mechanism orientations of earthquakes in southern California from 1982 to 1999, basing on a focal mechanism catalog from Hauksson. We find that for the two large earthquakes occurred in southern California, the 1992 Mw7.3 Landers and the 1999 Mw7.1 Hector Mine, the orientations of focal mechanisms near the coming earthquake tend to converge to the stress direction promoting the rupture of the coming earthquake and align with its focal mechanism about half-year before its occurrence, suggesting that the tectonic stress field gets more organized in favor of the rupture of the event pre-seismically. The degree of stress convergence is measured by the orientation angle RMS （root mean square） between the preshocks＇ focal mechanisms and the focal mechanism of the large event studied, and its time series recorded the stress convergence process. The degree of anomalies, measured by the F-tests, indicates that the convergence of stress orientations become significant at 90% confidence about half-year prior to both the Landers and Hector Mine quakes, and it becomes even more prominent at 99% confidence right before the occurrences. Our study may be of significance for assessment of regional seismic potentials.

A Class of Third-order Convergence Variants of Newton＇s Method

A class of third-order convergence methods of solving roots for non-linear equation,which are variant Newton＇s method, are given. Their convergence properties are proved. They are at least third order convergence near simple root and one order convergence near multiple roots. In the end, numerical tests are given and compared with other known Newton＇s methods. The results show that the proposed methods have some more advantages than others. They enrich the methods to find the roots of non-linear equations and they are important in both theory and application.

EMPIRICAL BAYES TEST PROBLEMS OF VARIANCE COMPONENTS IN RANDOM EFFECTS MODEL

Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that the proposed EB decision rules are asymptotically optimal with convergence rates near O(n-1/2). Finally, an example concerning the main result is given.

One-sided empirical Bayes test for location parameter in Gamma distribution

In this paper, we devote to constructing the one-sided empirical Bayes(EB) test for the location parameter in the Gamma distribution by nonparametric method. Under some mild conditions, we prove that the EB test is asymptotically optimal with the rate of the order O(n^(-δs/(2s+1))), where 1/2 ≤ δ < 1 and s > 1 is a given natural number. An example is also given to illustrate that the conditions of the main theorems are easily satisfied.

Empirical Bayes Test for Two-parameter Exponential Distribution under Type-Ⅱ Censored Samples

The empirical Bayes test problem is considered for scale parameter of twoparameter exponential distribution under type-II censored data.By using wavelets estimation method,the EB test function is constructed,of which the asymptotic optimality and convergence rates are obtained.Finally,an example concerning the main result is given.

基于CONVERGE软件的发动机燃烧室模型构建

发动机台架试验基于不同的工况,往往需要大量的试验,就导致试验成本居高不下。在如此庞大的的试验量下,就需要用到仿真软件来减少试验成本。美国Convergent Science Inc.开发的通用三维CFD软件Converge不仅包含了关于喷射、壁面薄膜、点火、湍流、燃烧和排放等过程的子模型以及一个化学反应的求解器SAGE,而且还成功地解决了CFD领域中非常棘手的动网格问题。文章通过本软件构建出燃烧室模型,并验证模型的准确性,为相关试验提供仿真方面的帮助。

基于新课标的中小学生计算思维量表构建研究

对学生计算思维的培养已成为数字时代的核心议题,科学、精准的评价则是培养学生计算思维能力的基础。然而,针对义务教育阶段学生的计算思维测评,目前国内尚无依托相关课程标准制定的本土化的、权威的量表。为此,研究首次依托《义务教育信息科技课程标准(2022年版)》(以下简称“新课标”)中的计算思维定义及培养要求,共以12920名(N1=1029,N2=1458,N3=10433)小学生和初中生为研究样本,运用收敛混合方法构建一个面向我国教育实际的、经严格论证的中小学生计算思维量表。结果显示:经过两轮的收敛混合分析,修改后的计算思维量表共包含5个因子及15个题项,具有良好的内容效度;经过大样本实证检验分析,量表具有良好的信效度,且具有跨性别、年级和地区测量等值性,可以用来测量中小学生的计算思维水平。

中国数字经济与实体经济:耦合协调及时空演变研究

本文基于2011—2022年30个省份的面板数据,建立数字经济与实体经济综合评价指标体系。运用耦合协调度、核密度分析、马尔可夫链及空间自相关等模型,对我国数字经济与实体经济的耦合协调度及时空演变特征进行测算分析。研究发现,我国数字经济与实体经济的耦合协调水平虽逐年提升,但由于各地区经济发展水平、产业结构、资源配置、数字技术与人才供给的非均衡性,导致空间不平衡现象明显,总体呈现“东高西低”的空间格局。区域内部分省份及产业集群凭借特定优势形成发展极,加剧了内部差异,呈现多极化演进趋势。“俱乐部收敛”现象反映出不同发展水平区域间的自我强化机制,导致等级锁定,难以迅速跨越发展鸿沟;莫兰指数呈现波动上升趋势,集聚程度缓慢提高,但在空间上集聚形态分布并不均衡,总体呈现“高高低低”的空间集聚特征。

一类Lindley模型参数的经验Bayes检验收敛速度的改进

利用递归核估计和单调性,构造了Lindley模型参数的经验Bayes检验函数,并在适当的条件下,证明了收敛速度的阶可任意接近O(n^(-1)).

梯级水库优化调度的改进ODDDP算法研究

“维数灾”问题和易陷入局部最优问题是梯级水库优化调度模型求解中的热点和难点。正交离散微分动态规划算法依据正交试验原理,解决了离散微分动态规划算法在求解水库群联合优化调度问题中的维数灾问题,但并未克服其依赖初始解质量和易陷入局部最优的缺陷。对此,借鉴入侵杂草算法空间扩散机制,引入高斯随机变量,并基于三角余弦函数的周期性质,设计提出了M-IWO-ODDDP算法,从算法全局搜索能力和搜索深度两方面,提高算法全局收敛能力。采用Schaffer、Shubert两种测试函数,分析测试了M-IWOODDDP算法的收敛性和鲁棒性。并以乌江流域11级梯级水库为例开展实例应用研究,结果表明,M-IWOODDDP寻优效果显著且对初始解质量无明显依赖性,算法收敛能力强、鲁棒性好。

我国金融发展收敛性测度与收敛机制检验

本文基于非线性时变因子模型对我国30个省级地区2005—2018年的综合金融发展水平指数进行检验,通过收敛内生识别算法对我国现存的金融收敛集团进行识别,并进一步对收敛集团的分布以及收敛路径变化进行分析。研究结果发现,我国金融发展整体不存在收敛的趋势,东、中、西、东北四大经济区域也均表现出发散特征。本文进一步内生识别出4个金融收敛集团,其分布呈现“高水平集团成员少,低水平集团成员多”的金字塔式形态,且低水平收敛集团与高水平收敛集团间差距明显,存在“东部发达,中、西以及东北欠发达”的金融极化现象。基于此,本文认为收敛集团间应“因地制宜”地采取差异化发展策略,集团内应构建竞争与合作并存的发展机制,从而加快金融收敛速度,促进各地金融水平协同发展。

我国农产品流通现代化水平评价、动态演进与收敛性

农产品流通现代化是中国式现代化的具体实践,也是促进小农户共同富裕、加快农业农村现代化、全面推进乡村振兴的重要驱动力。为研究现阶段我国农产品流通现代化特征,解决地区失衡等问题,探索推进农产品流通现代化协同提升路径,从农产品流通规模和效益现代化水平、组织和体制现代化水平、设施和服务现代化水平以及渠道现代化水平四个维度,构建农产品流通现代化水平评价体系,采用变异系数法测度2013—2021年全国30个省份的农产品流通现代化发展水平,并综合运用核密度估计、Dagum基尼系数及其分解、σ收敛、β收敛、俱乐部收敛和多元有序Logit模型深入剖析农产品流通现代化水平的动态演进、地区差异、收敛性特征及其驱动因素。研究发现:第一,全国整体农产品流通现代化水平偏低且提升缓慢,东部地区发展水平最高、增幅最大,中部地区发展大体呈倒V型态势,西部地区提升微弱,东北地区则有衰退趋势。全国整体存在两级分化现象,各地区内部农产品流通现代化发展不均衡,省际绝对差距有逐步扩大趋势,而东部地区内部省份差距最为突出。第二,全国整体及四大地区均不存在σ收敛,但普遍具有条件β收敛特征,表明不同地区农产品流通现代化水平并不会收敛于同一水平。综合考虑地区异质性后,各地区的农产品流通现代化水平趋近各自稳态。第三,农产品流通现代化水平存在跨地区收敛现象,在观测期内形成6个收敛俱乐部和1个存在发展障碍的发散组。低水平俱乐部中的省份可通过加大农业人力资本、物质资本投入和政府扶持力度等路径实现向高水平俱乐部跃进。经济增长可以促进已收敛于高稳态水平俱乐部的省份向更高水平跃迁。基于此,应客观认识并充分重视部分省份及地区农产品流通现代化水平增长缓慢、陷入衰退的事实。引入内部评估机制和地区排名制度,坚持因地制宜和分类精准施策齐头并进。加强地区间、省域间的空间联动性,实现农产品流通现代化水平跨地区协同提升。

Classification of Growth Clubs and Convergence: Evidence from Panel Data in China, 1981-2004

This paper uses provincial panel data to examine club convergence in China during 1981- 2004. We estimate the province-specific initial technology level, A（O）, and classify the Chinese economy into ＂developed club＂ and ＂underdeveloped club ＂ based on the economic characteristics of A（O）, instead of on geographical location. We find significant evidence of conditional convergence across provinces, and that the convergence speed in the developed club is faster than that in the underdeveloped club. We also find that.＂ （i） human capital accumulation contributes more than physical capital does to club convergence,＂ （ii） there is a positive correlation between infrastructure and growth convergence at the national level and within the developed club, while the spillover effect of infrastructure has not been developed in the developing club; and （iii） the effect of economic openness on convergence is tiny, and insignificant across and within clubs.

数字建设与高校科技创新效率协调发展分析

采用熵值赋权法、全局DEA-EBM模型、α收敛模型、β收敛模型和耦合协调模型测度评价2011—2021年中国31个省份数字建设水平和高校科技创新效率,并检验数字建设对高校科技创新效率的驱动耦合效应。研究发现,全国(未含港澳台地区)高校科技创新效率较低,总体呈波动下降趋势,并且东部地区下降幅度远超中西部地区;数字建设能有效驱动高校科技创新效率提升,加速各省份间高校科技创新效率差距的收敛速度,并且对东部地区的驱动作用力明显强于中西部地区;全国数字建设与高校科技创新效率间的耦合协调度总体呈稳定上升趋势,但东部地区耦合值明显高于中西部地区,东部地区早已进入初级协调阶段,并逐渐迈向中级协调状态,而中西部地区整体仍处于濒临失调阶段,近年来才逐渐转向勉强协调状态。由此从促进高校科技创新效率提升、推动数字建设发展和加强两者协同水平等方面提出相关建议。

中国文化产业全要素生产率的现状、地区差异与收敛性研究

文章基于2013—2021年中国31个省市自治区(因数据不全,本研究不含港澳台地区)文化产业的投入、产出数据,利用变系数生产函数测度了中国文化产业TFP,并运用描述性分析、Dagum基尼系数、变异系数、面板数据模型分析了中国文化产业TFP的现状、地区差异和收敛特征。研究发现:样本观测期内,中国文化产业TFP呈现逐年增长趋势,且表现出“由东部向西部渐次降低”的特征。中国文化产业TFP的地区差异逐年增大,并且区域间差异是中国文化产业TFP地区差异的主要来源。中国文化产业TFP不存在σ收敛特征,但存在绝对β收敛特征和条件β收敛特征。最后,基于研究结论,提出大力提升文化产业科技创新能力、实施区域协调发展战略、实施以强带弱抱团发展战略等建议,以期为缩小中国文化产业TFP地区差异及加快推进中国文化产业高质量发展提供经验参考。

偏态分布截断参数的经验Bayes检验

偏态分布是对称分布的一种推广,在实际生活中应用广泛,其中截断参数对界定偏态分布的边界具有重要意义.文中基于经验Bayes检验方法,研究了偏态分布截断参数的假设检验问题.考虑普通Bayes检验中先验密度的未知性和不确定性,利用递归核估计的密度函数代替未知的先验密度函数.定义检验的加权线性损失函数,从而更好地刻画了决策风险.在给定条件下证明了所提出检验函数的渐近最优性,同时给出确定的收敛速度.最后通过实例验证了文中的理论结果.

SOME IMPROVED PROJECTED QUASI-NEWTON ALGORITHMS AND THEIR CONVERGENCE Ⅱ.LOCAL CONVERGENCE RATE AND NUMERICAL TESTS

For the improved two-sided projected quasi-Newton algorithms, which were presented in PartI, we prove in this paper that they are locally one-step or two-step superlinearly convergent. Numerical tests are reported thereafter. Results by solving a set of typical problems selectedfrom literature have demonstrated the extreme importance of these modifications in making Nocedal& Overton's original methon practical. Furthermore, these results show that the improved algoritnmsare very competitive in comparison with some highly praised sequential quadratic programmingmethods.