人口圧による集約度上昇と一人あたり産出の変動 :モデル化の試み

抄録

In the paper we build the mathematical model based on Robinson and Schutjer (1984) and test whether it expresses Boserup's theory correctly. Boserup's theory insists that agricultural technology progress under human pressure and the production per capita is decreasing along this line. It is our result that this model works well under some definitions. This is good for Robinson and Schutjer but someone should think Boserup's theory itself is improper for expressing economic history. The production per capita has been increasing in history and this result is harmful for Ohshima's theory. Ohshima claims scarcity of lands is most important for the feudal system. It is sufficient that ruling lands to control peasants under such situation but if the production per capita decrease, no one want to stay their land in the feudal system. This means that if Ohshima's theory is true the output per capita should increase with human pressure. We agree this opinion and try to improve this model. To do so we include the effect of land accumulation in this model. Though land is expanded along with human pressure but a land per capita is decreasing. Under this condition our model expresses unique movement of the production per capita. If human pressure is not high, the output per capita decreases but if human pressure is high, the output per capita increases. This result is not suitable for Boserup's theory but supports Ohshima's opinion. As we said above increasing output per capita is requested if someone wants to control human by ruling lands. Of course this model is mathematical model so this result depends on the construction of our model. This means that this result is not universal validity but one of the unique opinion and we admit we should improve this model. But we believe it offers good base for future research.