Sampling from spatial databases

This paper deals with techniques for obtaining random point samples from spatial databases. We seek random points from a continuous domain (usually ²) which satisfy a spatial predicate that is represented in the database as a collection of polygons. Several applications of spatial sampling (e.g. environmental monitoring, agronomy, forestry, etc) are described. Sampling problems are characterized in terms of two key parameters: coverage (selectivity), and expected stabbing number (overlap). We discuss two fundamental approaches to sampling with spatial predicates, depending on whether we sample first or evaluate the predicate first. The approaches are described in the context of both quadtrees and R-trees, detailing the sample first, acceptance/rejection tree, and partial area tree algorithms. A sequential algorithm, the one-pass spatial reservoir algorithm is also described. The relative performance of the various sampling algorithms is compared and choice of preferred algorithms is suggested. We conclude with a short discussion of possible extensions.     

Overconfident investors and probability misjudgments

This paper explores systematic distortions of subjective probabilities by overconfident investors. In agreement with many non-expected utility theories, our devised setup acknowledges nonlinear weighting of physical probabilities by both rational and overconfident investors. Overconfidence – assumed to be higher after a history of gains and lower after a history of losses – changes these probability transformations. Using US asset price data, overconfident investors are found to be more optimistic than rational investors about future prospects.     

Gender,aging, and the economics of “active aging”: Setting a new research agenda

The world is aging, and the percentages of older people are on a dramatic ascent. This dramatic demographic aging of human society is not gender neutral; it is mostly about older women. One of the key policy approaches to address the aging revolution is known as “active aging,” crystalized by the WHO in 2002 by three pillars: participation, health, and security. The active aging policy has financial and economic aspects and affects both men and women. However, as argued in this article, a gender-based approach has not been adopted within the existing active aging framework. Therefore, a new gender-specific research agenda is needed, one that focuses on an interrelation between gender and different economic aspects of “active aging” from international, comparative, cultural, and longitudinal perspectives.     

French Yellow Vests (Gilets Jaunes): Similarities and Differences With Occupy Movements

The Yellow Vests movement in France was the most widespread and violent protest movement France has seen since 1968. This research highlights the resemblances and dissimilarities between the Yellow Vests and other Occupy movements. We find similarities in movement origins around suddenly revealed economic issues and relative deprivation. We also find that the Yellow Vests resemble other Occupy movements in terms of a combined strategy of a diffused and countrywide occupation of public spaces alongside weekly mass protest, and a lack of central organization and rejection of leadership. The Yellow Vests, however, differ from other Occupy movements in the extreme violence of the weekly demonstrations. Despite its rejection by the media, violence did not affect widespread public approval. In addition, the Yellow Vests achieved most movement objectives in spite of the lack of effective leadership with whom politicians could negotiate.     

On complexity and lotteries' evaluation – three experimental observations

We present experimental evidence suggesting that human subjects penalize lotteries for complexity. Our results contradict the assumption that human agents follow the discounted expected utility model in multi-period choice with uncertainty. In particular, we show that the buying price offered for an inferior, simple multi-period lottery may sometimes significantly exceed the buying price offered for a better, yet more complicated, alternative, when the lotteries are sold to a group of subjects in a first-price auction. We discuss the possibility to modify the existing models of choice to this “complexity effect”.     

The stages of mass mobilization: separate phenomena and distinct causal mechanisms

The notion that mass mobilization has analytically important stages is underappreciated in the literature. This paper proposes an approach that decomposes mass mobilization into three main phenomena: origins, protest and outcome. Each stage is characterized by unique factors and mechanisms. Accordingly, the research questions pertaining to each stage are dealt with by multiple levels of analysis and alternative explanations, allowing theory testing and theory development. The paper highlights separate causal mechanisms that operate in the emergence of grievances and protest motivation during the origins stage; mechanisms involving different forms of pressure, organization, psychological processes, and external forces during the protest stage; and mechanisms pertaining to key players and strategies that determine outcomes of mass mobilization. We illustrate that certain factors and mechanisms which are key in one stage have little or no causal relevance in the other stages. Other factors and mechanisms may also dramatically change in content, meaning or configuration between the stages. This theoretical approach facilitates the integration of a large and diverse body of scholarship into a structured analysis of mass mobilization that allows for both a detailed case study as well as comparison of stages across mass protests. The analysis of stages and causal mechanisms is illustrated across cases of democratization, revolution, and protest within democracy.     

The role of attribution of causality in economic decision making

Research has established that economic decisions often deviate from game theoretic predictions. We explore the process of causal thinking as a possible explanation for such deviations. Specifically, we suggest that causal information affects economic decisions based on the principles advocated by Weiner, 1985, Weiner, 1986 attribution theory (AT) of motivation and emotion. Prior research in this area considered only subsets of the dimensions employed by the theory. We test the predictions stemming from AT in contexts where economic decisions involve sharing gains between party members (e.g., splitting profits) and assess how such decisions are affected by the reasons attributed for obtaining the gains. Results indicate a significant link between causal attribution and economic decisions and shed light on the rules and the rationale that guide this link. We conclude that research into economic decision making should pay a greater attention to the explanatory value of AT.