A study on a farmland use accumulation factor by the supply and demand model considering stochastic choice

(1)问卷调查我们与农林渔业部负责人和地方政府合作，对稻农进行问卷调查，获取稻田租赁交易的反应数据。此外，调查还获得了农田和灌溉设施的数据。在问卷调查中，考虑匿名保护个人信息。(2)租赁交易模型的估计：基于随机选择模型，构建了农民将稻田出租给他人和从他人手中租赁稻田的反应函数，并利用问卷调查数据对反应函数进行了估计。在此基础上，建立了在供需平衡点上确定租金和租金协议水平的模型，并进行了仿真分析。(3)影响因素的阐明本研究通过模拟确定了公共工程对稻田的整治、逃避租金、水稻价格和工资的社会经济变量变化、稻田地理条件等因素对租金率和租金协议水平的影响。(4)适用性通过将真实租赁交易数据与模拟结果进行比较，检验了该模型的适用性。此外，通过该模拟定量评价了稻田固结工程的效果，并量化了日本租赁市场的经济损失。(5)结果发表本分析结果在国际会议上进行讨论，并在学术期刊上发表文章。

(1)Questionnaire surveyWe conducted questionnaire survey about rice farmers with cooperation of person in charge of the ministry of agriculture, forestry and fishery and local governments to get reaction data on a paddy-field rental transaction. In addition, the data on farmland and irrigation facilities were obtained by this survey. In questionnaire survey, anonymity was considered for protection of personal information.(2)Estimation of rental transaction modelReaction functions of farmers, who want to rent paddy-fields to others and to be rented from others, were formulated based on a stochastic choice model, and those functions were estimated by questionnaire data. Furthermore, the model which decides a rent and rental agreement level at the supply and demand balance point was built, and used for simulation analysis.(3)Elucidation of an influence factorThis study specified influence factors on rental rates and rental agreement level by simulations, such as consolidation of paddy-fields by the public projects, renting evasion, changes in social and economic variable of rice price and wages, and geographical condition of paddy fields.(4)ApplicabilityApplicability of this model was examined by comparing data in real rental transactions with a result of simulation. In addition, an effect of paddy-fields consolidation projects was evaluated quantitatively by this simulation, and an economic loss in a Japanese rental market was quantified.(5)Publication of resultResults of this analysis were discussed in the international conferences, and published as articles in academic journals.