# Ecological Dynamics and Evolution of Cooperation in Vehicular Ad Hoc Networks
## 2 Related Work  
Numerous studies have investigated methods to promote cooperation in VANETs. Among the most popular are incentive mechanisms and game theory approaches. Incentive mechanisms are designed to motivate vehicles to cooperate with one another. [PERSON] et al. proposed an incentive-aware routing protocol that uses a Tit-for-Tat (TFT) mechanism to maximize performance in Delay Tolerant Networks (DTNs) [4]. [PERSON] et al. developed a multilayer credit-based incentive system to encourage cooperation among DTN bundle nodes [5]. [PERSON] et al. tackled the free-riding problem in DTNs by introducing an incentive protocol that offers rewards to participating nodes to promote fairness [6]. [PERSON] et al. dealt with free-riding in VANETs by creating a honeypot that traps selfish vehicles in the network [7]. [PERSON] et al. developed an incentive-based protocol based on coalition game theory, in which vehicles have an incentive to forward data as members of a coalition to improve reliability and fairness in VANETs [8]. [PERSON] et al. designed an incentive system that uses the reciprocal altruistic factor to reconstruct the utility function of vehicles [9]. They demonstrated that their system can reduce message transmission delay by up to 30% compared to other cooperative transmission mechanisms. Additionally, [PERSON] et al. proposed an incentive mechanism from the perspective of behavioral economics that incorporates the anchoring effect and loss aversion on offloading in the Internet of Things [10]. They introduced the reference factor and price-break discount factor based on the anchoring effect and time pressure and regret value on loss aversion to encourage nodes to participate in data offloading. [PERSON] et al. developed a mechanism with both incentives and punishments for VANET [11]. In this mechanism, vehicles with higher weight and cooperation are elected as Heads during the election process. Vehicles that participate in the election can increase their reputation by cooperating in forwarding data, while those who exhibit repeated selfish behavior are punished. In addition, game theory has been utilized to address the issue of free-riding in wireless network routing [12]. Game theory approaches can be broadly classified into two categories, pairwise and collective games. Pairwise games assume that interactions between players are limited to two players only, where the effect of a player's strategy is only on one other player. On the other hand, collective games assume that interactions are collective, meaning that the strategy of one player can impact several other players' strategies. The collective game category includes public goods games (PGG) and coalition games. Previous studies have investigated the problem of cooperation in VANETs using game theory, and have utilized a model with pairwise interactions [13; 14; 15; 16; 17; 18; 19]. This means that the effect of each player, or vehicle, is assumed to be limited to only one other companion player. However, this assumption may not be appropriate for the effect of forwarded messages, since each player can actually affect multiple other vehicles simultaneously. Therefore, other studies have considered the effect of each player on multiple other vehicles simultaneously, which is a more suitable assumption for the problem at hand. While models with pairwise interactions are commonly used in game theory, their results cannot always be extended to games with collective interactions, and may lead to misleading conclusions [20]. The cited studies have contributed to the investigation of cooperation in VANETs through game theoretical models. [PERSON] et al. [13] proposed a cooperative information dissemination scheme for vehicular networks using a Markov decision process. [PERSON] et al. [15; 18] proposed a cooperative content sharing mechanism using evolutionary game theory. [PERSON] et al. [16] considered the problem of finding stable cooperative strategies in VANETs using a repeated game approach. [PERSON] et al.