Pompeu Fabra University

About: Pompeu Fabra University is a education organization based out in Barcelona, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 8093 authors who have published 23570 publications receiving 858431 citations. The organization is also known as: Universitat Pompeu Fabra & UPF.

A Price is a Social Thing: Towards a Material Sociology of Arbitrage

Abstract: Arbitrage is a form of trading crucial both to the modern theory of finance and to market practice, yet it has seldom been the focus of study outside of economics. This article draws upon four initially separate ethnographic and interview-based studies to sketch a ‘material sociology’ of arbitrage. (The article follows financial market usage in viewing ‘arbitrage’ as trading that exploits discrepancies in relative prices, trading which is seldom the entirely riskless arbitrage posited by finance theory.) Prices are physical entities, and the extent and speed of the mobility of these entities are crucial to arbitrage. Traders' bodies sometimes need to be trained to conduct arbitrage, and the relative placement of different bodies can be crucial. Arbitrage generally involves a theory of the similarity of different assets, and material representations of relative value are often required in order to check the theory's plausibility. Arbitrageurs need to convince themselves and others such as investment-bank m...

*Protestants and Catholics: Similar Work Ethic, Different Social Ethic

Abstract: This article develops two hypotheses about economically-relevant values of Christian believers, according to which Protestants should work more and more effectively, as in the “work ethic” argument of Max Weber, or display a stronger “social ethic” that would lead them to monitor each other’s conduct, support political and legal institutions and hold more homogeneous values. Tests using current survey data confirm substantial partial correlations and possible different “effects” in mutual social control, institutional performance and homogeneity of values but no difference in work ethics. Protestantism therefore seems conducive to capitalist economic development, not by the direct psychological route of the Weberian work ethic but rather by promoting an alternative social ethic that facilitates impersonal trade.

The Affective Slider: A Digital Self-Assessment Scale for the Measurement of Human Emotions.

Abstract: Self-assessment methods are broadly employed in emotion research for the collection of subjective affective ratings. The Self-Assessment Manikin (SAM), a pictorial scale developed in the eighties for the measurement of pleasure, arousal, and dominance, is still among the most popular self-reporting tools, despite having been conceived upon design principles which are today obsolete. By leveraging on state-of-the-art user interfaces and metacommunicative pictorial representations, we developed the Affective Slider (AS), a digital self-reporting tool composed of two slider controls for the quick assessment of pleasure and arousal. To empirically validate the AS, we conducted a systematic comparison between AS and SAM in a task involving the emotional assessment of a series of images taken from the International Affective Picture System (IAPS), a database composed of pictures representing a wide range of semantic categories often used as a benchmark in psychological studies. Our results show that the AS is equivalent to SAM in the self-assessment of pleasure and arousal, with two added advantages: the AS does not require written instructions and it can be easily reproduced in latest-generation digital devices, including smartphones and tablets. Moreover, we compared new and normative IAPS ratings and found a general drop in reported arousal of pictorial stimuli. Not only do our results demonstrate that legacy scales for the self-report of affect can be replaced with new measurement tools developed in accordance to modern design principles, but also that standardized sets of stimuli which are widely adopted in research on human emotion are not as effective as they were in the past due to a general desensitization towards highly arousing content.

Color image enhancement via chromaticity diffusion

Abstract: A novel approach for color image denoising is proposed in this paper. The algorithm is based on separating the color data into chromaticity and brightness, and then processing each one of these components with partial differential equations or diffusion flows. In the proposed algorithm, each color pixel is considered as an n-dimensional vector. The vectors' direction, a unit vector, gives the chromaticity, while the magnitude represents the pixel brightness. The chromaticity is processed with a system of coupled diffusion equations adapted from the theory of harmonic maps in liquid crystals. This theory deals with the regularization of vectorial data, while satisfying the intrinsic unit norm constraint of directional data such as chromaticity. Both isotropic and anisotropic diffusion flows are presented for this n-dimensional chromaticity diffusion flow. The brightness is processed by a scalar median filter or any of the popular and well established anisotropic diffusion flows for scalar image enhancement. We present the underlying theory, a number of examples, and briefly compare with the current literature.