Persuasive games have great properties for facilitating lasting attitude change for complex societal issues, making them a valuable tool for achieving attitude change towards cooperation and information sharing that is often necessary for effective multi-actor decision-making. It is assumed that persuasive game design principles are key drivers for conceiving successful persuasive games, however, their effect on attitude change and attitude reinforcement has not been validated. To get one step closer towards validated persuasive game design principles, this research aimed at validating the most frequently used persuasive game design principles for persuasive game for multi-actor decision- making: simulation. Game experiments in the form of laboratory experiment were conducted to control for possible confounding variables. Three versions of an existing game were conceived in which the persuasive game design principle simulation was varied. A mixed methods approach was used in which both quantitative and qualitative measures were conducted to assess the effect of the persuasive game design principle simulation on attitude change. Based on current findings it cannot be confirmed nor denied that the persuasive game design principle has affected attitude change regarding cooperation and information sharing. Still, the main scientific contribution of this research is the creation of a sufficient method for evaluating the effect of persuasive game design principles on attitude change in isolation which did not consist yet. Further research on the methodology is advised to validate its effect and for fine-tuning. Additionally, it is advised to conduct this research with a greater sample size in this future.

Persuasive games for complex systems have subtle messages they want to convince stakeholders of the complex system of in question of in order to help them solve certain problems. However, there currently is little known about the persuasive game design principles used in those games to convey the persuasive message, especially how people with different cultural backgrounds perceive the persuasiveness of the persuasive design principles. This paper describes the research executed to determine how Individualists and Collectivists perceive the persuasiveness of 'Comparison between individuals' and 'Comparison between groups', this was done using a combination of a persuasive game for complex systems and storyboards. The results showed that Individualists are persuaded more by 'Comparison between groups' than by 'Comparison between individuals' which was not expected. Further research using another persuasive game for complex system should determine whether this was due to the game or is also valid for other persuasive game for complex systems.