How effective is the quality constraint mechanism of agricultural socialized services?—Evidence from 1,138 farmers in Shandong, China

Constraint mechanisms of agricultural socialized services have been widely established, but how effective is the quality constraint mechanism remains unclear. However, the existing literature has not provided an answer to this question. Therefore, this study theoretically analyzes the effect of quality constraint mechanism on agricultural socialized service and propose the hypothesis, then applies MESR model and 1,138 farmers survey data, empirically examines the impact of constraint mechanism. The study finds that: (1) The constraint mechanism has a positive impact on the quality of agricultural socialized services. Based on contract theory, the intermediary mechanisms focus on two aspects: implicit contracts of trust within familiar societies and explicit contracts of risk-sharing. (2) Under the consideration of counterfactual hypothesis, if farmers with low constraint do not construct constraint mechanisms, the quality of agricultural socialized services will decline by 22%. If farmers with high constraint do not construct constraint mechanisms, the quality of agricultural socialized services will decline by 33%. (3) The results of heterogeneity analysis show that the effect of quality constraint mechanisms on different farmers is in the order of part-time farmers, small-scale pure farmers, and large professional farmers. The influence of quality constraint mechanism on different crops is in the order of vegetable, corn, and wheat. Accordingly, the government should guide farmers in signing service contracts, optimize the service standards system. This study can provide both theoretical and practical guidelines for the construction of constraint mechanisms of agricultural socialized services.