Ambiguous Contracts

In this paper we initiate the study of ambiguous contracts, capturing many real-life scenarios where agents engage in contractual relations that leave some degree of uncertainty. Our starting point is the celebrated hidden-action model and the classic notion of a contract, where the principal commits to an outcome-contingent payment scheme for incentivizing an agent to take a costly action. An ambiguous contract generalizes this notion by allowing the principal to commit to a set of two or more contracts, without specifying which of these will be employed. A natural behavioral assumption in such cases is that the agent engages in a max-min strategy, maximizing her expected utility in the worst case over the set of possible contracts. We show that the principal can in general gain utility by employing an ambiguous contract, at the expense of the agent's utility. We provide structural properties of the optimal ambiguous contract, showing that an optimal ambiguous contract is composed of simple contracts. We then use these properties to devise poly-time algorithms for computing the optimal ambiguous contract. We also provide a characterization of non-manipulable classes of contracts - those where a principal cannot gain by employing an ambiguous contract. We show that linear contracts - unlike other common contracts - are non-manipulable, which might help explain their popularity. Finally, we provide bounds on the ambiguity gap - the gap between the utility the principal can achieve by employing ambiguous contracts and the utility the principal can achieve with a single contrac

A framework for comparative institutional research on HRM

This article argues that awareness of institutional context has been singularly lacking in the most influential areas of HRM. This lack of attention to external context has resulted in findings that fail to reflect reality. We offer a layered contextual framework embedded in economic institutional theory. We propose that it forms the basis of a comparative research agenda for HRM. We validate the framework using extant publications on institutionally based comparative HRM, drawing on findings from the Cranet research network published in the decade 2007–2017

Subclinical atherosclerosis in Behcet's disease: A systematic review and meta-analysis.

OBJECTIVE: To evaluate subclinical atherosclerosis in Behcet disease (BD), we performed a systematic review and meta-analysis of studies where atherosclerosis was determined by flow-mediated dilatation (FMD) and endothelial-mediated dilatation (EMD) and by measurement of intima media thickness (IMT) of carotid arteries. METHODS: Systematic search of EMBASE and PubMed databases from January 2000 to January 2014 according to PRISMA guidelines. RESULTS: Nine studies met the inclusion criteria on FMD/EMD, 11 on IMT and 4 on both. BD had lower FMD than controls (SMD = -0.89, 95% CI: -0.660 to -1.11, p < 0.001), which was confirmed by subgroup analyses on active and inactive patients (SMD = -1.17, 95% CI: -1.45 to -0.89 and SMD = -0.72, 95% CI: -0.97 to -0.46, p = 0.0001 for both). EMD was lower in BD but with a large estimate (SMD = 0.38, 95% CI: -0.79 to -0.03, p = 0.06, I(2) = 82.2%). IMT was greater in BD and the large estimate (SMD = 0.95, 95% CI: 0.63-1.28, p < 0.0001, I(2) = 87.6%) persisted after subgroup analysis on active and inactive patients (I(2) = 88.4% and 86.7%, respectively). Pooling IMT studies by a Newcastle Ottawa Scale of 5 and 6/7 yielded lower estimates (SMD = 0.54, 95% CI: 0.32-0.75, p < 0.0001, I(2) = 58.7% and SMD = 1.72, 95% CI: 1.35-2.09 p < 0.05, I(2) = 48.6%). CONCLUSIONS: FMD is impaired in BD even in inactive state and IMT is greater despite a degree of statistical heterogeneity that reflects the clinical heterogeneity of BD. Future prospective studies should account for risk stratification of atherosclerosis in BD

Astro2020 APC White Paper: The Early Career Perspective on the Coming Decade, Astrophysics Career Paths, and the Decadal Survey Process

In response to the need for the Astro2020 Decadal Survey to explicitly engage early career astronomers, the National Academies of Sciences, Engineering, and Medicine hosted the Early Career Astronomer and Astrophysicist Focus Session (ECFS) on October 8-9, 2018 under the auspices of Committee of Astronomy and Astrophysics. The meeting was attended by fifty six pre-tenure faculty, research scientists, postdoctoral scholars, and senior graduate students, as well as eight former decadal survey committee members, who acted as facilitators. The event was designed to educate early career astronomers about the decadal survey process, to solicit their feedback on the role that early career astronomers should play in Astro2020, and to provide a forum for the discussion of a wide range of topics regarding the astrophysics career path. This white paper presents highlights and themes that emerged during two days of discussion. In Section 1, we discuss concerns that emerged regarding the coming decade and the astrophysics career path, as well as specific recommendations from participants regarding how to address them. We have organized these concerns and suggestions into five broad themes. These include (sequentially): (1) adequately training astronomers in the statistical and computational techniques necessary in an era of "big data", (2) responses to the growth of collaborations and telescopes, (3) concerns about the adequacy of graduate and postdoctoral training, (4) the need for improvements in equity and inclusion in astronomy, and (5) smoothing and facilitating transitions between early career stages. Section 2 is focused on ideas regarding the decadal survey itself, including: incorporating early career voices, ensuring diverse input from a variety of stakeholders, and successfully and broadly disseminating the results of the survey

Air pollution and the microvasculature: A cross-sectional assessment of in vivo retinal images in the population-based multi-ethnic study of atherosclerosis (MESA)

10.1371/journal.pmed.1000372PLoS Medicine711