* We thank David Bruner for his assistance in running these experiments and the University of Calgary Behavioural and Experimental Economics Laboratory for providing the facilities to conduct the experiments. Funding for this project was provided by the Social Sciences and Humanities Research Council (Canada) via a grant to McKee. 2 ABSTRACT Models for voluntary provision of public goods predic...

Recommender systems try to facilitate the decision making process of users, by recommending products such as movies, music and news articles. This work uses a user based recommender system to predict redemption probabilities of different gift cards. That is, the probability that a user redeems a gift card in a store, given that he or she receives it. This work is a base for ranking gift cards i...

In this paper, we develop a newsvendor model in which the retailer gives ‘‘free’’ gift cards to consumers who purchase a regularly priced product at the end of the selling season instead of discounting the product. The model is developed for a market with patient consumers. We derive the sufficient optimality condition for the retailer’s stocking level in the first period and the optimal gift c...

Many insects have a mating system where males transfer nutrients to females at mating, which are often referred to as ‘nuptial gifts ’. Among butterflies, some of the characteristic features of these species are polyandry (females mate multiple times), and relatively large male ejaculates. When males produce part of the resources used for offspring, the value of body size might then increase fo...

Force or coercion are often a part of sexual relationships in South Africa, especially among adolescents. This coercion is also often pinioned by an economic exchange: gifts or favours for sex. Studies have pointed out the negative consequences of the exchanges which are often characterised by large age differences ('sugar dad-dies') or power imbalances. Perhaps more pervasive but largely ignor...

The article addresses the problem of reciprocity in homoerotic relationships classical Athens. According to more traditional approach, pecking ord er model ’’, these typically a symmetrical almost inevitably involved humiliation one partners, who literally or metaphorically assumed passive and therefore u n manly role. Although recent studies tend underline arti fici al cha racter schola rly re...