Group decision making in agriculture: Mathematical programming model + Group Decision Support System approach
As part of her secondment to ALSIA, Ana Esteso from UPV conducted a teaching session. At the session, an introduction to the group decision making in agriculture was presented. For that, an approach comprised by a multi-objective mathematical programming model and a group decision support system was employed to centrally plan the planting and harvest of crops. The main complexity of this planning problem is that prices of products are highly dependent on demand-supply balance. So, decisions made by one farmer will impact on the margin to be obtained by the rest of farmers. This could be solved by centrally planning the planting and harvest of products, but new problems could arise due to the inequalities between farmers and consequently, their unwillingness to collaborate. A multi-objective mathematical programming model to centrally plan the planting and harvest of three types of tomatoes is proposed. Three objectives related to three dimensions of sustainability are optimized by using the ε-constraint method. Ten non-dominated optimal solutions are obtained and included in the group decision support system named GRUS as possible planning alternatives. Involved actors use the group decision support system to vote, in function of their preferences, the alternatives that better fit their needs. In this way, farmers collaboratively decide the solution to be implemented in farms. The involvement of farmers in decision-making process provokes the willingness to implement chosen decisions in real life. Results obtained by applying this group decision making approach to the Argentinean tomato case study are presented. Possible future lines for the improvement of such approach are commented and discussed with the audience.
The presentation is available for download here