Our survival and wellness require a balance between optimism and pessimism. Undue pessimism makes life miserable; however, excessive optimism can lead to dangerously risky behaviors. A review and synthesis of the literature on the neurophysiology subserving these two worldviews suggests that optimism and pessimism are differentially associated with the two cerebral hemispheres. High self-esteem...

We present a code transformation for concurrent data structures, which increases their scalability without sacrificing correctness. Our transformation takes lock-based code and replaces some of the locking steps therein with optimistic synchronization in order to reduce contention. The main idea is to have each operation perform an optimistic traversal of the data structure as long as no shared...

Qualitative counterparts of expected utility can be expressed by means of Sugeno inte-grals. Both von Neumann and Morgenstern-like and Savage-like axiomatic justiications are provided. In this framework, pessimistic (i.e., risk-averse) as well as optimistic attitudes can be captured.

In the model of Funaki and Yamato (1999) the tragedy of the commons can be avoided with pessimistic players, while this does not hold for optimistic players. We propose a new core concept to overcome this puzzle and provide numerical simulations of simple games where the conclusions coincide or are less sensitive to behavioural assumptions.

In this paper, we propose a task redundancy strategy based on measures of accuracy of volunteers. Simulation results show that our strategy reduces the number of generated task replicas compared to the pessimistic and moderate strategies. It also generates similar or less task replicas compared to the optimistic strategy.

In this paper, we prove an exponential rate of convergence result for a common estimator of conditional value-at-risk for bounded random variables. The bound on optimistic deviations is tighter while the bound on pessimistic deviations is more general and applies to a broader class of convex risk measures. © 2007 Elsevier B.V. All rights reserved.

This paper presents a new protocol for atomic broadcast in an asynchronous network with a maximal number of Byzantine failures. It guarantees both safety and liveness without making any timing assumptions or using any type of “failure detector.” Under normal circumstances, the protocol runs in an “optimistic mode,” with extremely low message and computational complexity — essentially, just perf...

INTRODUCTION US tobacco control policies to reduce cigarette use have been effective, but their impact has been relatively slow. This study considers a strategy of switching cigarette smokers to e-cigarette use ('vaping') in the USA to accelerate tobacco control progress. METHODS A Status Quo Scenario, developed to project smoking rates and health outcomes in the absence of vaping, is compare...

Cognitive bias is a phenomenon that presents in clinical populations where anxious individuals tend to adopt a more pessimistic-like interpretation of ambiguous aversive stimuli whereas depressed individuals tend to adopt a less optimistic-like interpretation of ambiguous appetitive stimuli. To further validate the chick anxiety-depression model as a neuropsychiatric simulation we sought to qua...