In this paper, we explore the use of the web as an environment for electronic commerce. In particular, we develop a novel mechanism that creates incentives for honesty in electronic marketplaces where human users are represented by buying and selling agents. In our mechanism, buyers model other buyers and select the most trustworthy ones as their neighbors from which they can ask advice about s...

The risk factors for compulsive exercise are unknown. This study aims to explore longitudinal sociocultural risk factors for compulsive exercise, using a 12-month prospective design. A sample of 332 male and female adolescents (aged 13-15 years at baseline) completed self-report measures of sociocultural risk factors and compulsive exercise at baseline and eating disorder psychopathology and co...

This paper evaluates performance of human subjects and instances of a bidding model that interact in continuous-time double auction experiments. Asks submitted by instances of the seller model (“automated sellers”) maximize the seller’s expected surplus relative to a heuristic belief function, and arrive stochastically according to an exponential distribution. Automated buyers are similar. Acro...

Problem statement: Due to a behavior of buyers effects to a growth of marketing, then a group of agreement of buyers and buyers’ behavior on eventually placing orders are investigating. Approach: In this study, a discrete-time consensus protocol for a scale-free buyer networks is proposed. Herein, an initial purchase intention of each buyer is defined to be active or non-active and an impulse s...

In the context of electronic commerce, the problem of unfair ratings arises when modeling the trustworthiness of a selling agent relies (partially) on propagation of ratings provided by buying agents that have personal experience with the seller. Extreme diversity of open and dynamic electronic marketplaces causes difficulties in handling unfair ratings in trust management systems. To ease this...

Exercise can be used as a mood regulator but, in the eating disorder literature, exercise has sometimes been found to be compulsive, detrimental to physical health, and regarded as one maladaptive strategy used to regulate emotions. This study examined longitudinal associations between emotion regulation styles and this compulsive exercise in 572 adolescents who completed measures of compulsive...

OBJECTIVE To investigate whether people who buy wine buy healthier food items than those who buy beer. DESIGN Cross sectional study. SETTING Supermarkets in Denmark. Data Information on number, type of item, and total charge from 3.5 million transactions over a period of six months. RESULTS Wine buyers bought more olives, fruit and vegetables, poultry, cooking oil, and low fat cheese, mil...

I show that the presence of informed buyers is necessary but not always su cient for producers to use prices as signals of product quality. A su ciently high fraction of informed buyers eliminates the lemons problem. A small fraction of informed buyers mitigates the lemons problem, provided that buyers' prior belief of high quality is su ciently pessimistic : price reveals high quality at a sig...