Evolutionary Game for Optimizing Green Investment of Supply Chain Based on Contract

This paper establishes an evolutionary game model of supply chain green investment strategy based on contract, and analyzes the evolution process, stable strategy and its influencing parameters of the green investment strategy chosen by the manufacturer and distributor. The results show that the excess returns obtained by both parties through bilateral and economic penalties based on contract provide positive incentives for both parties, and the cost of investment and the spillover benefits obtained through the other party's investment have a negative impact on both parties. The results also show that both manufacturers and distributor will not choose to invest when the sum of the excess returns obtained by both parties through unilateral investment and the reward obtained through unilateral investment is smaller than the investment costs, and the difference between the excess returns obtained by both parties through bilateral investment and investment costs is smaller than the difference between the spillover benefits obtained through the other party's investment and the punishment received due to their unilateral not investing. And both manufacturers and distributor will choose to invest when the sum of the excess returns obtained by both parties through unilateral investment and the reward obtained through unilateral investment is greater than the investment costs, and the difference between the excess returns obtained by both parties through bilateral investment and investment costs is greater than the difference between the spillover benefits obtained through the other party's investment and the penalty received due to their unilateral not investing.