Joint impact of multiple observations on a subset of variables in multiple linear regression

In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSE_ij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), F_j (Partial F-test for the jth variable) and F_j(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSE_IJ, F_J and F_J(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.     

How can David orchestrate resources to enhance firm performance? A dynamic approach to coping with resource constraints

Given that the possession of abundant resources does not always guarantee superior firm performance, this study proposes a dynamic approach to enhancing firm value. Building on the resource orchestration thesis, we investigate how firms facing resource constraints enhance their capabilities over time by orchestrating resources and how this resource orchestration can play a role in improving firm performance. Using the dynamic perspective, this study identifies four resource orchestration modes, which are specified based on how a given firm dynamically allocates its resources to technology (enacted by R&D activities) and marketing (enacted by advertising activities). Accordingly, we claim that firms with resource constraints can enhance their performance by escalating or altering their resources over time. To test our hypotheses, we used a sample of 4078 small and medium-sized enterprises in manufacturing industries between 1984 and 2018. We found that focus escalation for technology positively affects firm performance, captured by Tobin's q, and that focus alternation toward either technology or market is positively related to firm performance. Finally, we discuss the theoretical and practical implications of our findings.     

Who Pays? Can We Pay Them Back?

This chapter is about a very old question that is thrown up again in discussion related to ANT. Do orders have necessary limits to what can belong to them? It is possible to read ANT as containing or demanding a moral commitment to the inclusion of the disenfranchised. It can often seem to be in the business of giving credit where credit is due, spreading recognition to even the most unexpected quarters. To sustain itself such a morality would depend on the possibility of infinite inclusion. By identifying this picture of 'belonging-by-assemblage' and its traditional counterpart 'belonging-by-banishment' and by finding both at play within ANT, the papers argues that ANT is an ethical rather than a moral enterprise, bringing the unanswered question of the nature of belonging to bear across domains, rather than approaching each domain with a 'cookie-cutter' moral formula. The disturbing 'unsecuring' of belonging that ANT involves continues within the philosophical tradition ANT trades on and contributes to in the form of an abiding controversy over the place of the natural world.     

Sex preference versus number preference: the case of Korea

The author argues that the effect of sex preference must be disentangled from the effect of number preference in Korea. This study tests--with hazard models--the effect of the number of previous children on the next birth according to the sex composition of previous children. Data were obtained from the 1974 Korean Fertility Survey. This paper also analyzes the timing of childbearing in recent periods in order to determine whether replacement-level fertility is temporary or permanent. The ideal number of children declined from 3.9 children in 1965 to 2.1 in 1991. The age-specific fertility rates for ages 20-24 years declined rapidly during the late 1980s. The fertility rates among women aged 25-29 years and 30-34 years increased during 1985-90. The proportion of fertility among women aged 20-29 years increased from 67.9% in 1975 to 86.6% in 1984. Women born in the late baby boom period of the late 1950s to mid-1960s reached prime reproductive age during the late 1980s and 1990s, but the crude birth rate remained about the same during 1985-92. A higher percentage of women (22.4%) born during 1955-59 remained single in 1990. During 1960-90, the percentage of women aged 20-24 years who were married declined. These trends indicate later age at childbearing and an explanation for the temporary nature of below-replacement fertility in the late 1980s. Korean women did not want to have more than 2 children, and the interval between first and second births increased since 1985. Among pregnancies of parity 2 conceived since 1985, over 90% of women with at least one son ended subsequent pregnancies by abortion compared to only 59% without sons. Hazard models of 1974 data reveal that son preference had an important effect on fertility. Fertility was higher among women with only daughters. Findings suggest that the value of sons must be measured at the societal and not at the individual level.     

The role of public health in population health

The role of public health is central in population health. What distinguishes public health from clinical medicine is that it's focus is on the entire population--not the individual patient. To achieve the goal of population health, healthy communities, or Healthy People 2000 requires physician leadership in medicine and public health at all levels--local, state, and national. The challenge is formidable, but the goals are attainable through strategies that focus on the goal of the common good and through collaboration of public health, medicine, and the community.     

消费者品牌信任机制建立及影响因素的实证研究

诚信危机是现代企业面临的严峻问题,而营销领域关于消费者对品牌信任建立的理论与实证研究还很匮乏。笔者在访谈和文献基础上,将相关领域的机制性研究与前因性研究两种方法相结合,提出了消费者品牌信任建立的三种机制(经验机制、计算机制和转移机制),并探查出能够反映每种机制的五个变量(感知质量、顾客满意、感知风险、经济价值和品牌声誉)。通过在化妆品行业收集的数据,使用结构方程模型分析,结果表明,经验机制和计算机制对建立品牌信任起作用,其中经验机制的作用最大。     

中国股票市场的信息反应曲线和股票价格波动的非对称性

股票价格波动对于市场信息的反应过程具有非对称性。通过利用多种非对称性GARCH 模型,描述和检验了沪市股票日收益率序列的条件波动性,并通过对股票市场信息影响曲线的分析,发现沪市股票价格波动中存在显著的非对称性反应。这说明股市波动对于不同的政策干预和信息冲击具有不同程度的反应,“利好消息”对股市的刺激作用仍然需要其他市场干预的配合才能发挥出来。     

基于医疗质量的公立医院绩效体系构建研究

目的：运用德尔菲法构建一套科学、可操作的公立医院绩效评价体系。方法：采用文献法研究国内外绩效评价理论,结合问卷结果形成初始量表。通过德尔菲法对指标进行两轮筛选及优化。结果：初步形成由“社会效益”、“质量安全”、“运行效益与效率”为基本结构的指标体系,包括3个一级指标、13个二级指标和72个三级指标。结论：该指标体系重点关注医院公益性及内涵质量,对公立医院绩效评价具有一定参考意义。