Materials are available for download in the Files section. A note from Dr. Halevy: 1. The original study was conducted at the Hebrew University of Jerusalem, Israel. Participants were all male, Israeli students, which means that the vast majority of them had served in the military for several years; they were also exposed to high levels of intergroup violence (the study was conducted at the Hebrew University of Jerusalem and there were numerous terrorist attacks on buses and restaurants in Jerusalem in the years leading up to the study). This fact might be important given the topic of the study - willingness to participate in integroup conflict. 2. Many participants received partial course credit (toward a 10-hour participation in experiment requirement associated with an introductory psychology course) in addition to the monetary incentives (which means some of them cared about credit more than the money or vice versa). The flat bonus of you will see in the instructions was designed to prevent participants from losing any money in the experiment. 3. Incentives were in Israeli Shekels given that the study was conducted in Israel. I mention this because research in judgment and decision making has shown than nominal values of incentives also matter, in addition to absolute monetary value. The data were collected in 2005 (I am not sure what was the exchange rate then between U.S. dollars and Israeli Shekels, but you could look it up in case you care about that ratio). 4. The study used paper-and-pencil materials rather than computers. My own experience in other projects involving economic games suggests that this aspect of the procedure matters. The Hebrew version I attach includes the decision form we used (in the IPD-MD condition; in the IPD-MD condition with communication and the IPD condition relevant information was added / omitted based on condition). 5. Participants in our sample were 24 years old on average (which is consistent with the several years of compulsory military service mentioned in point #1 above); this is slightly older than what you get with a typical undergraduate sample here in the U.S. A couple of other things: 1. Some folks have already replicated some of the main results reported in the study, in case that is of any interest to you. One paper is De Dreu et al. (2010) in Science. Other folks who have recently used the same materials I just sent you actually share a university affiliation with you - in case you would like to reach out to them (Jonah Schulhofer-Wohl and Beatrice Boulu-Reshef -- University of Virginia Darden School of Business and Department of Economics). 2. We had 240 participants (80 3-person teams) in the original study.