Social information has been shown to influence a diversity of human decisions : household energy and water consumption, charity giving, student alcohol use... These behavior changes however entail limited monetary costs or even reduce costs for the decision maker. Does the effect of social information stand in the context of costly decisions?
Irrigation is a key input to ensure optimal crop yield in many contexts throughout the world. Yet, the reduction of water use by farmers is a key challenge considering the current and expected modification of rainfall patterns and the resulting reduction of water resources available for irrigation. However, reducing water use may potentially incur significant costs for farmers by reducing yields. In this experiment, we intend to test whether providing social information may contribute to the reduction farmers' water use for irrigation. The potential effect of peer behavior relies on the assumption that farmers have upward biased beliefs on the behavior of others. Correcting these biases may incline farmers to reduce water use for two reasons: i) to conform to the social norm and/or ii) because they may be reassured by the fact that others are reasonable and are not over-consuming water.
Our experiment takes the opportunity of the installation of irrigation smart-meters in 3 watersheds in the South West of France. These smart-meters communicate daily to the Irrigation Scheme Manager (ISM) the amount of water used by farmers. The principle of the experiment will therefore be to test the effect of providing weekly social information on water use coming from these smart-meters on individual farmers' irrigation decisions.