倒向随机微分方程中非参数估计的核函数选择

比较了多种类型的核函数下倒向随机微分方程（BSDE）中生成元z的非参数估计方法,利用不同的核函数估计BSDE中的生成元z的非参数估计,在均方误差意义下比较了8种不同的核函数下得到的BSDE的生成元z的非参数估计的精度,统计分析结果显示Gaussian核函数下的估计效果最好。     

新产业空间的崛起及其对上海大都市区空间组织的影响

本文以劳动空间分工理论为分析工具,着重从理论和实证两个方面分析上海市郊区工业园作为一种新产业空间的崛起,进而探讨其对上海大都市区空间组织的影响。     

《线性代数》课程教学改革初探

《线性代数》为高等院校的三大基础数学课之一,它的重要性不言而喻.本文结合《线性代数》自身的特点,初步探讨了教学过程中应注意的几个问题,以期达到提高该课程教学质量和教学效果的目的.     

Cumulative Response to Sequences of Terror Attacks Varying in Frequency and Trajectory

There is a paucity of research examining public response to the cumulative effects of multiple related extreme events over time. We investigated the separate and combined effects of frequency and trajectory of terrorist attacks. A scenario simulation of a series of gas station bombings in Southern California was developed to evaluate respondents' affect, risk perception, and intended avoidance behavior using a 3 (frequency; low vs. medium vs. high) by 3 (trajectory; increasing vs. constant vs. decreasing) factorial design. For each of the nine conditions, three videos were created to simulate news broadcasts documenting the attacks over a three‐week period. A total of 275 respondents were included in the analysis. Results from analysis of covariances (ANCOVAs) indicate that trajectory of the sequential attacks (increasing or decreasing in frequency) predicts negative affect, risk perception, and avoidance behavior. In contrast, frequency predicts neither negative affect, positive affect, risk perception, nor intended avoidance behavior. Results from structural equation modeling (SEM) further indicate that the effect of negative affect on behavioral intention is mediated by risk perception and the effect of trajectory on risk perception is partially mediated by negative affect. In addition, both ANCOVAs and SEM model results suggest that (1) females experience less positive affect and perceive more risk than males, (2) respondents with higher income perceive more risk, and (3) younger respondents are more likely to modify their behavior to avoid the risk of future attacks.     

服务型企业动态能力的测量研究

服务业的快速增长不仅表明经济发展阶段的变化,也赋予服务型企业崭新的历史使命.在复杂多变的外部环境下,服务型企业如何应对客户个性化的需求,适应技术变革及盈利模式变化带来的冲击,提升对客户需求和环境变化的响应速度,成为服务型企业面临的主要问题.为了应对内外部环境的不确定性,动态能力成为服务型企业形成持续竞争优势的主要保障.借鉴已有学者的的研究成果,并结合服务型企业的特征,从资源配置能力、学习能力、创新能力、环境感知能力和环境适应能力等5个维度提出了服务型企业动态能力的构成.借助SPSS和Amos应用探测性因子分析和验证性因子分析方法,对量表中的题项进行了删减,并验证了量表的有效性,通过对5个维度的相关性分析,可以发现环境感知能力对其他维度的影响最大,提升服务型企业动态能力主要应从提升企业环境感知能力入手.     

几类三阶非线性微分方程的通解（通积分）公式

提出几类三阶非线性微分方程，借助首次积分法及降阶法，给出这几类方程的通解或通积分的公式。     

中立型Timoshenko射线方程的强迫振动性

研究了中立型Ｔｉｍｏｓｈｅｎｋｏ射线方程４ｔ４〔ｕ＋λｕ（ｘ，ｔ－τ）〕＋ａ２ｕｔ２－ｂ４ｕ２ｘｔ２＋ｃ４ｕｘ４＋Ｃｘ，ｔ，ｕ，ｕ（ｘ，σ（ｔ））＝ｆ（ｘ，ｔ），（ｘ，ｔ）∈Ｊ×Ｒ＋解的强迫振动性，其中Ｊ＝（０，Ｌ），Ｒ＋＝（０，∞），λ，ａ，ｂ，ｃ为非负常数，τ＞０是常数，ｕ＝ｕ（ｘ，ｔ）．     

Local orthogonal polynomial expansion for density estimation

A local orthogonal polynomial expansion (LOrPE) of the empirical density function is proposed as a novel method to estimate the underlying density. The estimate is constructed by matching localised expectation values of orthogonal polynomials to the values observed in the sample. LOrPE is related to several existing methods, and generalises straightforwardly to multivariate settings. By manner of construction, it is similar to local likelihood density estimation (LLDE). In the limit of small bandwidths, LOrPE functions as kernel density estimation (KDE) with high-order (effective) kernels inherently free of boundary bias, a natural consequence of kernel reshaping to accommodate endpoints. Consistency and faster asymptotic convergence rates follow. In the limit of large bandwidths LOrPE is equivalent to orthogonal series density estimation (OSDE) with Legendre polynomials, thereby inheriting its consistency. We compare the performance of LOrPE to KDE, LLDE, and OSDE, in a number of simulation studies. In terms of mean integrated squared error, the results suggest that with a proper balance of the two tuning parameters, bandwidth and degree, LOrPE generally outperforms these competitors when estimating densities with sharply truncated supports.     

A note on information theoretic measures

An axiomatic characterization of an information theoretic quantity is given using only two axioms. In particular, this quantity contain PEARSON'S chi-square statistic and some other useful measures     

城市创新能力的溢出效应与空间分布——对江苏省13地市的实证分析

城市创新能力的溢出受地理距离的限制,形成以创新能力强的城市为中心、创新能力弱的城市在边缘的"中心—边缘"空间格局。利用新经济地理学的空间自相关模型,分析江苏省13城市创新能力的空间分布特征,结果表明:城市创新能力具有明显的区域差异性,空间分布对创新型城市的发展有重要影响,城市之间呈现较强的空间依赖性和差异性,并初步形成了创新集群的"核心—边缘"空间分布格局。要实现创新型城市的快速健康发展,应打破空间约束,增强城市间技术创新的溢出效应,进而促进自身创新能力的提高。