Confounding and collinearity in regression analysis: a cautionary tale and an alternative procedure,illustrated by studies of British voting behaviour

Quality & Quantity - Many ecological- and individual-level analyses of voting behaviour use multiple regressions with a considerable number of independent variables but few discussions of their...     

Multi-unit auctions with budget limits

We study multi-unit auctions for bidders that have a budget constraint, a situation very common in practice that has received relatively little attention in the auction theory literature. Our main result is an impossibility: there is no deterministic auction that (1) is individually rational and dominant-strategy incentive-compatible, (2) makes no positive transfers, and (3) always produces a Pareto optimal outcome. In contrast, we show that Ausubel?s “clinching auction” satisfies all these properties when the budgets are public knowledge. Moreover, we prove that the “clinching auction” is the unique auction that satisfies all these properties when there are two players. This uniqueness result is the cornerstone of the impossibility result. Few additional related results are given, including some results on the revenue of the clinching auction and on the case where the items are divisible.     

Random coefficients models of arms imports

This paper uses a large panel of data with up to 19 time-series observations for almost 150 countries to estimate models of arms imports. Qualitative evidence suggests a non-linear relationship. As income and military expenditure grow, the propensity to import first rises and then falls as a domestic arms industry develops. We face the difficulty that there is virtually no data on domestic arms procurement or production capability. We respond to this difficulty by adopting a random coefficient approach in order to identify any systematic influences on import propensity, through the impact of military expenditure, size of the armed forces or income on unobserved domestic production capability. While a clear non-linear pattern is apparent in the cross-section relationship, once one allows for parameter heterogeneity such a pattern is not apparent in the time-series.     

When an NGO Takes on Public Participation: Preparing a Plan for a Neighborhood in East Jerusalem

It is often non‐governmental organizations (NGOs) that promote empowered participation processes, and assume active roles in leading them. However, the ability of NGOs to take on such processes is under‐theorized. In many cases empowered participation involving NGOs takes place without political support from above (or with limited or conditional support). Our goal in this article is to use a case study of participatory planning in East Jerusalem to theorize processes of empowerment in an oppositional political environment. We argue that it is useful to analyze such processes of empowered participation through the concept of power. We describe the process of empowerment as a speculative process in which the NGO has to hedge two mediums of power: it has to build the power of the community to discuss its own goals; and it has to simultaneously manage the transfer of decision‐making power from government bodies to the community.     

A systematic review of cost-effectiveness modeling of pharmaceutical therapies in neuropathic pain: variation in practice,key challenges,and recommendations for the future

Objectives: Complexities in the neuropathic-pain care pathway make the condition difficult to manage and difficult to capture in cost-effectiveness models. The aim of this study is to understand, through a systematic review of previous cost-effectiveness studies, some of the key strengths and limitations in data and modeling practices in neuropathic pain. Thus, the aim is to guide future research and practice to improve resource allocation decisions and encourage continued investment to find novel and effective treatments for patients with neuropathic pain.

Methods: The search strategy was designed to identify peer-reviewed cost-effectiveness evaluations of non-surgical, pharmaceutical therapies for neuropathic pain published since January 2000, accessing five key databases. All identified publications were reviewed and screened according to pre-defined eligibility criteria. Data extraction was designed to reflect key data challenges and approaches to modeling in neuropathic pain and based on published guidelines.

Results: The search strategy identified 20 cost-effectiveness analyses meeting the inclusion criteria, of which 14 had original model structures. Cost-effectiveness modeling in neuropathic pain is established and increasing across multiple jurisdictions; however, amongst these studies, there is substantial variation in modeling approach, and there are common limitations. Capturing the effect of treatments upon health outcomes, particularly health-related quality-of-life, is challenging, and the health effects of multiple lines of ineffective treatment, common for patients with neuropathic pain, have not been consistently or robustly modeled.

Conclusions: To improve future economic modeling in neuropathic pain, further research is suggested into the effect of multiple lines of treatment and treatment failure upon patient outcomes and subsequent treatment effectiveness; the impact of treatment-emergent adverse events upon patient outcomes; and consistent and appropriate pain measures to inform models. The authors further encourage transparent reporting of inputs used to inform cost-effectiveness models, with robust, comprehensive and clear uncertainty analysis and, where feasible, open-source modeling is encouraged.     

实验设计的新前沿

产品和过程开发是业务长期生存的基础，生存和成功的关键是培养创新和减少产品上市时间，同时使产品到达最佳性能。     

Dimensions and Levels of Trust: Implications for Commitment to a Relationship

Previous research has found that trust is positively related to commitment in buyer-seller relationships. However, the validity of this finding is questionable because trust has been operationalized in many different ways. For example, prior research has not distinguished among levels of trust (interpersonal or organizational trust) and dimensions or motives of trust (credibility or benevolence). In this study, we distinguish among the levels and dimensions of trust. The results indicate that trust in a sales representative (interpersonal credibility) is more strongly related to commitment than trust in an organization (organizational credibility). In contrast, trust based on organizational benevolence is a stronger predictor of commitment than interpersonal benevolence.