本文以Frankel(1986)及Lai, Hu and wang (1996)之理論架構爲基礎，建立涵蓋農產品與製造業產品（或非農產品）兩部門的封閉經濟體系模型，據以探討：以農產品市場干擾導致農產品價格波動爲因，政府穩定農產品價格爲果，搭配體制崩潰的題材，分析農產品價格、製造業產品價格以及政府對農產品購買量的動態走勢。經由本文之分析可知，當政府所訂定之農產品價格的門檻水準高於未設門檻之新均衡水準時，農產品市場出現干擾致使供給大增之際，原爲自由浮動的農產品價格體制會瞬間崩潰爲固定門檻的農產品價格體制，政府因應地調高農產品的購買量。然若政府所訂定之農產品價格的門檻水準低於未設門檻之新均衡水準時，農產品市場出現干擾後，農產品價格將持續下跌，政府爲穩定農產品價格而設置農產品價格下限門檻的措施，反而造成最終農產品價格水準的跌幅較不干預時爲高，亦即助長了價格的不穩定。

According to the theoretical frameworks of Fankel (1986) and Lai, Hu and Wang (1996), we set up a closed economy model including two sectors of agricultural and manufactured products. When there is a disturbance in the agricultural market and the government fries to stabilize agricultural prices above the minimum price that was set by the government, we analyze the dynamic process of agricultural prices, manufactured prices and purchase amount of the government for agricultural products. We find that when the initial threshold of agricultural prices is higher than the new equilibrium level, the price regime of agricultural products will collapse instantaneously from being flexible to being regulated because of the increase in supply of agricultural products caused by disturbance of agricultural market. Meanwhile, the government will raise purchase amount for agricultural products to keep agricultural prices equal to the threshold level. But if the initial threshold of agricultural prices is lower than the new equilibrium level, agricultural prices will continuously decrease and be more unstable comparing to the situation that government did nothing about agricultural prices.