Understanding Social Change in Conducting Research on Adolescence

In the present essay, we focus on G. Stanley Hall's contributions to the study of the role of social change for adolescent development. After introducing Hall's main ideas, we discuss recent demands adolescents face because of social change and how Hall's work could inform research on adolescent development in times of social change.     

Temporal Aggregation of Stationary and Non-stationary Continuous-Time Processes

Abstract.  We study the autocorrelation structure of aggregates from a continuous-time process. The underlying continuous-time process or some of its higher derivative is assumed to be a stationary continuous-time auto-regressive fractionally integrated moving-average (CARFIMA) process with Hurst parameter H . We derive closed-form expressions for the limiting autocorrelation function and the normalized spectral density of the aggregates, as the extent of aggregation increases to infinity. The limiting model of the aggregates, after appropriate number of differencing, is shown to be some functional of the standard fractional Brownian motion with the same Hurst parameter of the continuous-time process from which the aggregates are measured. These results are then used to assess the loss of forecasting efficiency due to aggregation.     

第6章新官上任

《龟航》是一部职场小说, 同时也是一部代表了特定人群的小说,在这个大时代下,境遇变迁,冲击着每一个人。海归的遭遇更能折射出现实的意义。本刊现独家连载这部原创作品。您从作者清新幽默的文笔下读到的将是新世纪《围城》的深刻和感同身受。     

挑战人生

《龟航》是一部职场小说, 同时也是一部代表了特定人群的小说,在这个大时代下,境遇变迁,冲击着每一个人。海归的遭遇更能折射出现实的意义。本刊现独家连载这部原创作品。您从作者清新幽默的文笔下读到的将是新世纪《围城》的深刻和感同身受。     

Venture philanthropy and social entrepreneurship in community redevelopment

This article provides a case study of Tom Cousins, a social entrepreneur who used his own venture philanthropic investments and leveraged additional resources through extensive public‐private partnerships for the sole intent of redeveloping an area of disinvestment and poverty. In the process, Cousins also provided the visionary, strategic, and operational leadership often associated with the actions and responsibilities of a social entrepreneur. The limited research to date has investigated social entrepreneurship and venture philanthropy as separate and often unrelated concepts. In this study, we analyze the sustained and intensive involvement by Cousins and his foundations and the continued leadership provided in the creation of public‐private partnerships focused on the redevelopment of the East Lake area in Atlanta.     

A class of partially linear single‐index survival models

The authors define a class of “partially linear single‐index” survival models that are more flexible than the classical proportional hazards regression models in their treatment of covariates. The latter enter the proposed model either via a parametric linear form or a nonparametric single‐index form. It is then possible to model both linear and functional effects of covariates on the logarithm of the hazard function and if necessary, to reduce the dimensionality of multiple covariates via the single‐index component. The partially linear hazards model and the single‐index hazards model are special cases of the proposed model. The authors develop a likelihood‐based inference to estimate the model components via an iterative algorithm. They establish an asymptotic distribution theory for the proposed estimators, examine their finite‐sample behaviour through simulation, and use a set of real data to illustrate their approach.     

论停滞与失败——思想意识形态与历史:两个初步的问题(之一)

理学作为一种思想体系受到朝廷的推崇,并作为科举考试的组成部分。在20世纪,对理学的看法发生了分歧。有人认为理学是智识与科学进步的障碍,中国要想走向现代化就必须摆脱理学。关于中国在12世纪后进入长时期停滞的看法,历史学界一般都不赞成了,但读者的这种看法还比较强烈。对于中国历史的一些基本特征的认识需要重新检验,比如中国文化不是只有一个起源;中国并非与外界隔离并拒绝外界影响;中国的政治体制不是绝对独裁;中国文化并没有一个纯正的“正统”或“道统”(orthodox);中国人并非没有自主的完整实体的“自我”观念。学者在实际研究中往往把中国当作一个实体民族或一个连续不断的文明体,这种观念并不太准确,实际是误解了China的原意。