Estimation of causal effects in observational studies with interference between units

Causal effects are usually estimated under the assumption of no interference between individuals. This assumption means that the potential outcomes for one individual are unaffected by the treatments received by other individuals. In many situations, this is not reasonable to assume. Moreover, not taking interference into account could result in misleading conclusions about the effect of a treatment. For two-stage observational studies, where treatment assigment is randomized in the first stage but not in the second stage, we propose IPW estimators of direct and indirect causal effects as defined by Hudgens and Halloran (J Am Stat Assoc 103(482):832–842, 2008) for two-stage randomized studies. We illustrate the use of these estimators in an evaluation study of an implementation of Triple P (a parenting support program) within preschools in Uppsala, Sweden.     

Bringing About Changes to Corporate Social Policy through Shareholder Activism: Filers,Issues, Targets,and Success

We examine shareholder initiated social policy proposals' capacity to exert pressure on management to force it to adopt the suggested changes in policy. We show that social proposals, filed under the U.S. Securities and Exchange Commission's Rule 14a‐8, have a more limited capacity to change corporate social policy than it has been previously reported. However, the capacity to exert pressure on firms can be substantially higher for some types of filers, notably pension funds and mutual funds. The analysis also suggests that the capacity to influence management is higher for some types of issues presented in the resolution, such as those related to board diversity, energy and environment, and international laborand human rights. We also provide suggestions explaining why shareholder activism is a persistent practice despite its limited results.     

Does Ownership Form Matter for Corporate Social Responsibility? A Longitudinal Comparison of Environmental Performance between Public,Private, and Joint‐venture Firms

This study examines whether a firm's ownership form has any influence on its social performance. Conventional wisdom suggests that public (publicly traded) corporations are more susceptible to corruption and socially irresponsible behavior than privately owned corporations because of the intense short‐term profit maximization pressure from shareholders and the lack of sufficient monitoring mechanisms. This study introduces an alternate perspective in thinking about the relationship between ownership form and corporate social responsibility. This study reasons that public corporations are more likely to become socially responsible because of their greater exposure to external influence and greater dependence on external actors with diverse interests. Using a panel data on the pollution management practices of 118 industrial facilities over a 13‐year period, this study shows that public corporations were indeed subject to greater external pressure to reduce pollution, and the pressure led to consistently stronger environmental performance.     

The Microeconomics of Efficient Group Behavior: Identification1

Consider a group consisting of S members facing a common budget constraint p'ξ=1: any demand vector belonging to the budget set can be (privately or publicly) consumed by the members. Although the intragroup decision process is not known, it is assumed to generate Pareto‐efficient outcomes; neither individual consumptions nor intragroup transfers are observable. The paper analyzes when, to what extent, and under which conditions it is possible to recover the underlying structure—individual preferences and the decision process—from the group's aggregate behavior. We show that the general version of the model is not identified. However, a simple exclusion assumption (whereby each member does not consume at least one good) is sufficient to guarantee generic identifiability of the welfare‐relevant structural concepts.     

THE ORGANIZATION OF THE INNOVATION INDUSTRY: ENTREPRENEURS,VENTURE CAPITALISTS,AND OLIGOPOLISTS

We construct a model where incumbents can either acquire basic innovations from entrepreneurs, or wait and acquire developed innovations from entrepreneurial firms supported by venture capitalists. We show that venture‐backed entrepreneurial firms have an incentive to overinvest in development vis à vis incumbents due to strategic product market effects on the sales price of a developed innovation. This will trigger preemptive acquisitions by incumbents, thus increasing the reward for entrepreneurial innovations. We also show that venture capital can emerge in equilibrium if venture capitalists have cost advantages, or if development is associated with double moral hazard problems. (JEL: G24, L1, L2, M13, O3)     

LINGUISTIC DIVERSITY AND REDISTRIBUTION

This paper investigates the effect of linguistic diversity on redistribution in a broad cross‐section of countries. We use the notion of “linguistic distances” and show that the commonly used fractionalization index, which ignores linguistic distances, yields insignificant results. However, once distances between languages are accounted for, linguistic diversity has both a statistically and economically significant effect on redistribution. With an average level of redistribution of 9.5% of GDP in our data set, an increase byone standard deviation in the degree of diversity lowers redistribution by approximately one percentage point. We also demonstrate that other measures, such as polarization and peripheral heterogeneity, provide similar results when linguistic distances are incorporated. (JEL: D6, D74, H5, Z10)     

寻求价值均衡：现代和谐宪政建构的必由之路

审视现代西方宪政制度运行所面临的诸多问题和价值冲突,本文认为,寻求政治价值的某种均衡与和谐,是现代宪政发展的必然选择。寻求政治价值均衡既是现代社会多元利益关系相互博弈的合理抉择,也有着厚实的理论基础。从政府权力运用这一维度来考察,实现政治价值均衡的路径主要是解决公共权力"有限"与政府"有为"之间的关系问题。解决权力"有限"的核心是建构多元化的、相互补充的有机控权机制;实现政府"有为"的基础是塑造有效政府,保障政府治理在实现公共性、公平性、回应性、开放性、合作性、凝聚性等方面积极有为,增进社会和谐。     

The potential power of social policy programmes: income redistribution,economic resources and health

Lundberg O, Fritzell J, Åberg Yngwe M, Kölegård ML. The potential power of social policy programmes: income redistribution, economic resources and health Int J Soc Welfare 2010: ??: ??–??© 2010 The Author(s), Journal compilation © 2010 Blackwell Publishing Ltd and International Journal of Social Welfare. This Supplement includes a number of articles dealing with the role of social policy schemes for public health across the life course. As a key social determinant of health, poverty and its consequences have historically been at the forefront of the public health discussion. But also in rich countries today, economic resources are likely to be important for health and survival, both on an individual and an aggregate level. This introductory article serves as a background for the more specific analyses that follow. The focus is on why income and income inequality could have an effect on individual and population health. We discuss relationships between the individual and population levels and between income and health, and some of the possible mechanisms involved. We also present arguments for why welfare state institutions may matter.     

Some tests for uniformity of circular distributions powerful against multimodal alternatives

The author introduces new statistics suited for testing uniformity of circular distributions and powerful against multimodal alternatives. One of them has a simple expression in terms of the geometric mean of the sample of chord lengths. The others belong to a family indexed by a continuous parameter. The asymptotic distributions under the null hypothesis are derived. We compare the power of the new tests against Stephens's alternatives with those of Ajne, Watson, and Hermans‐Rasson's tests. Some of the new tests are the most powerful when the alternative has three or four modes. A heuristic justification of this feature is given. An application to the analysis of archaeological data is provided. The Canadian Journal of Statistics 38:80–96; 2010 © 2010 Statistical Society of Canada     

Electricity consumption prediction with functional linear regression using spline estimators

A functional linear regression model linking observations of a functional response variable with measurements of an explanatory functional variable is considered. This model serves to analyse a real data set describing electricity consumption in Sardinia. The interest lies in predicting either oncoming weekends’ or oncoming weekdays’ consumption, provided actual weekdays’ consumption is known. A B-spline estimator of the functional parameter is used. Selected computational issues are addressed as well.