Ch3 The Behavior of Consumers

MRS 邊際替代率

indifference curve 上邊際效用都一樣

移動時改變量 0

在 indifference curve 的最佳點，indifference curve 切 budget line 因此 MRSxy = 斜率 = (1/Py) / (1/Px) = Px/Py

凸性偏好

MRS 遞減

Laspeyres price index & Paasche price index

Laspeyres price index = old basket 新的價格 / 過去的價格

e.g.

過去 Px = $2, Py = $2，最佳 basket 為 (15,30)
現在 Px = Py = $1
Laspeyres price index = (151+301) / (152+301) = 3/4 (102上期中 1. (e) ii)
make things look worse than they are

Paasche price index = new basket 新的價格 / 過去的價格
track the new basket
make things look better than they are

Cardinal Utility vs. Ordinal Utility

Cardinal Utility: 商品有絕對價值

e.g. 1 顆蘋果 = 10 單位價值

Ordinal Utility: 商品只有相對價值

e.g. 1 顆蘋果 = 3 顆橘子

Cardinal and Ordinal Utility

Problems & Homeworks

重點題目

31.(d)

0<a,b<1

---

作業

題目

Answer