交易额、A 股比例、势效应和三因子模型

利用回归和构造动态投资组合方法,对中国股票市场1995 年7 月到2000 年12 月股票 月收益率、交易额、总市值及其财务数据进行分析,发现中国股票市场具有显著的交易额效应、 A 股比例效应、市值效应、账面市值比效应等. 这些效应有密切的相互关系,但不能用市场beta 值来解释. 市场beta 值、市值因子、账面市值比因子一起,也就是Fama2French 三因子模型,可以 很好地解释这些效应     

二维GPSJ分布类及其在保险中的应用

本文给出的二维GPSJ分布类(即GPSJ2)在保险领域应用范围较广,如由机动车辆保险由财产损失索赔次数和人身伤亡索赔次数所组成的模型、超额再保险中的由自留保单数和分出报单数所组成的二维模型等。本文在GPSJ1类基础上研究二维GPSJ类,本文给出了此分布类的定义、背景意义、概率计算的递推公式,同时还对各参数的最大似然估计值的求解过程进行了分析。本文最后将这一模型应用于一组机动车辆赔付次数数据,考虑了由财产损失索赔次数、人身伤亡索赔次数组成的二维模型,拟合效果令人满意。     

县级政府、供应链管理与农产品上行关系研究

基于中国13省87个电子商务进农村示范县的调研材料,分析政府项目驱动下农产品上行问题。实践表明,政策利好为县域农产品电商发展提供了试错空间,“S2B2C”的供应链管理模式对农产品上行的推动作用明显。但是,多数县级政府未能认识到供应链管理之于农产品上行的作用,普遍存在政府治理方式滞后、公共服务网络不健全、农产品区域公用品牌缺乏、冷链等基础设施投入不足等问题。因此,为有效推动农产品上行,政府应进一步推动“公私合作”、构建一体化的公共服务、注重品牌营销、优化产品供应链管理。     

A comparison of approaches for estimating the effect of women's education on the probability of using modern contraceptive methods in Malawi

The aim of this study is to estimate the effect of education on the probability of married Malawian women using modern contraceptive methods by accounting for both observed and unobserved confounders. We conduct a sensitivity analysis and compare the results of naive models with instrumental variable models to account for the potential endogeneity of education. Our findings demonstrate conflicting results between the two modelling approaches. The naive models report smaller education effects on the probability of using modern contraceptive methods compared to instrumental variable models. We also find that by relaxing the functional form assumption on the effect of continuous covariates, using a flexible instrumental variable model, the education's effect follows a positive, nonlinear pattern. This finding is not observed with a classic instrumental variable model.     

Symptoms of Eating Disorders Among Females in Drug Addiction Treatment

The aim of this study is to measure and describe symptoms of eating disorders among females in treatment for drug addiction in Norway. Previous clinical and epidemiological studies have revealed coprevalence between eating disorders and substance use or abuse. However, few studies have measured eating disorders in drug-using samples and even fewer within the context of drug treatment. In this study, 29 females with drug use disorder in residential treatment were tested with the Eating Disorder Inventory–2. A subgroup of 9 females (31%) with significant symptoms of eating disorders was identified. The characteristics of this group and possible clinical consequences are discussed.     

犍陀罗本生雕刻的印度文化母题

犍陀罗本生雕刻作为印度文化母题的视觉化形式,以叙事性图像生动地阐释印度民间广泛推崇的价值观。犍陀罗本生雕刻的文化母题包括具有普世意义的乐善好施的传统;以轮回报应为理论基础,以孝敬忠贞为核心的伦理道德观念;奉行虔诚于神和克制苦行的修身理念。这些文化母题真实地再现了古代印度人民的社会理想、家庭关系和人生追求,是今人理解古印度文化的可靠资料。     

Power comparison of the Kolmogorov–Smirnov test under ranked set sampling and simple random sampling

Many studies have been used to compare the power of several goodness-of-fit (GOF) tests under simple random sampling (SRS) and ranked set sampling (RSS). In our study, a different design procedure and ranking process in RSS are thoroughly investigated. A simulation study is conducted to compare the power of the Kolmogorov–Smirnov test under SRS and RSS with different sets and cycle sizes for several distributions. Level-2 sampling design and partially rank-ordered sets are used. Also, we benefited from auxiliary variables in the ranking process. Finally, results are presented with tables and figures. Under these conditions we show that the RSS has better performance against the SRS in finite population.     

Business reform outcomes: Why so different?

Post-crisis policy making increasingly focuses on doing business reforms. We argue that the effects of those reforms will be different across countries. To understand the reasons for the reform outcome divergence, we advance a novel firm-size distribution (FSDs) argument. At the center of the argument is the fact that FSDs are different across countries and stable over time. Then, if a given doing business reform induces firms of different size to grow differently, this will produce a variety of reform outcomes across countries. To advance the argument, we set up a tractable general equilibrium (GE) model and study how firms of different size grow after a doing business reform. The model predicts that larger firms will grow faster than smaller firms after the reform. The model predictions are tested on the Enterprise Surveys (ES) data, merged with the Doing Business indicators. We confirm that firms of different size grow differently after a Doing Business reform. Thus, based on the notable differences of firm size distributions across countries, identical reforms to start, operate and close a business will produce a variety of reform outcomes across countries.     

Goal attainability and performance: Evidence from Boston marathon qualifying standards

In this paper we test if performance improves once goals become more attainable. Goal-setting literature suggests that workers respond to challenging but achievable goals with increased performance. Empirical evidence supports the notion of goals increasing performance; however the evidence on how attainability of goals affects performance is mixed. This paper tests whether efforts increase, improving performance as the goals become more attainable. We are employing a unique set of publicly available marathon data from 1970 to 2015 to directly analyze the effect of goal attainability on performance. With the probable goal of qualifying for the Boston Marathon, we test if runners increase their effort, and consequently improve their performance if they enter a new age group and as a result have a more attainable goal. We find that runners who enter a new age group perform better than the runners whose qualifying time did not change. This effect is seen with runners in younger age groups, but not found in the results of runners in more advanced years.     

论九色鹿本生的图文传播

《九色鹿》是著名的佛本生故事，其在中土的图文传播有同有异。从传播内容言，二者所关注的人物形象都集中在九色鹿、国王、告密者以及国王夫人身上，但文学的传播内容，总体上较图像传播更丰富些。从传播途径言，图像传播线路较为明确，可归纳为“印度→犍罗陀→中土”，而文学传播似有断层。从传播时间之先后言，图像的叙事传播略早于文学传播，但文学传播持续时间更长，一直持续到宋元以后。无论图、文叙事，都受到了中土固有文化的影响。