数理計画モデル分析における気象リスク評価方法の拡張に関する一考察

―気象リスクを考慮した水稲乾田直播栽培の経営的評価を事例として―

抄録

A mathematical programming model is effective in both farm planning and managerial evaluation of farming systems. This paper evaluates the possibility of introducing direct seeding rice in dry paddy fields by using such a model. In the model, the possible machine work time restrictions that are decided by the hourly precipitation data of the past 10 years are considered. Moreover, based on the estimated machine work time, the study uses the method of 100,000 random samplings with replacement to obtain 100,000 sets of estimations of possible machine work time. Each of these sets is incorporated into the model and the optimal solutions are calculated. By comparing the optimal solutions for the past 10 years, and an estimation with the optimal solutions of 100,000 times simulation, it is verified that the proposed method is appropriate and useful for more possibilities are considered by using this method.