Many everyday situations are characterized by a social dilemma structure. Imagine, for instance, a situation in which the inhabitants of two villages intend to build a bridge over a river that divides both villages. The bridge would be beneficial for both villages by improving trades and reducing traveling costs, and so on. Building the bridge would necessitate a certain amount of money, which people would have to contribute to the project in order to realize it. Everybody would potentially benefit from the bridge, so the social goals would be maximized if the bridge was built. Let us assume that all contributions are voluntary and it is not possible to force anybody to pay because there is no law that allows this. Let us further assume that no one can be effectively excluded from using the bridge. In such a situation, for each person it would be optimal to save their own share and to free-ride on other people’s contributions. In abstract terms, a social dilemma is characterized by socially efficient behavior (here: all contribute money to the bridge) standing in conflict with individual interests (here: saving the money). It is surprising how many situations in the real world have such a structure. For example, actions of environmental protection (e.g., buying an electrically powered car or the more expensive natural deodorant), decisions about paying for public television or transportation, voting, or situations in your private entourage like investing in a group present for a friend’s birthday. All of these examples have one thing in common: you can decide whether you want to cooperate or free-ride. Many of these situations occur repeatedly. In highly controlled laboratory studies, behavior in social dilemma situations is often investigated in prisoner dilemma tasks (Rapoport and Chammah 1965) or, in their generalized form, public-good games. There is much research on the factors influencing cooperation in public-good games. One of the crucial factors seems to be people’s social orientations (Balliet et al. 2009; Fehr and Fischbacher 2002; Fischbacher and Gächter 2010; Offerman et al. 1996; Van Lange et al. 1997a). Social value orientation (SVO) is
assumed to be some kind of enduring personality structure that can be measured by assessing the preferences for particular distributions of outcomes to oneself and others in so-called “decomposed games” (Kuhlman and Marshello 1975; Liebrand and McClintock 1988; Van Lange et al. 1997b). However, one of the interesting findings is that SVO is mainly predictive for behavior in so-called one-shot games, but not for situations in which people play public-good games repeatedly (Park 1994; Renkewitz et al. 2011). Overall, relatively little is known about the underlying processes mediating the relation of SVO and contributions. In the current study, two goals are pursued: first, the study aimed at investigating people’s willingness to contribute to public goods in repeated social dilemma situations, depending on their SVO. Second, and more importantly, the cognitive processes involved in decision-making in a social dilemma situation should be investigated using advanced eye-tracking technology. Here, the relationship between people’s SVO is of special interest, as well as the question of whether this orientation can relate to enduring characteristics of the information search processes. This is one of the first studies to investigate decision processes in strategic games on a fine-grained level using eye-tracking (but see Costa-Gomes and Crawford 2007; Crawford 2008; Knoepfle et al. 2009). This allows monitoring and analyzing subjects’ information search processes as well as the arousal connected with certain types of behavior (e.g., freeriding vs. cooperating).