II-Theories-3 Flashcards
Investor utility
function
Capital Allocation Line CAL
- 是什么
- 性质2
- a portfolio of a risk-free asset and risky asset
- 一条直线,不同点代表组合中两种资产权重
标准差即risky asset的标准差*权重
From a portfolio of 2 assets,
evolve to
Effective Frontier
Effective Frontier Chart
- 横轴/纵轴
- Minimum-variance frontier
- Global Minimum-Variance Portfolio
- Effective Frontier
- From Effective Frontier to
Optimal Risky Portfolio (chart)
- why it’s optimal?
- 见图
- 无风险资产与Effective Frontier上其余任何一点连接,组成的portfolio中都可以找到一点,CAL比其相同risk但return更高
from Optimal risky portfolio
+ risk-free asset
evolve to
Optimal Investor Portfolio
Capital Market Line CML
- 由来
- 横纵轴
- 斜率
- 原optimal risky portfolio=,包含
- 描述方程
- CAL由于每个投资者对不同组合收益的perseptive不同,会有多个。
CML假设所有投资者预期相同,客观存在一个最好的market portfolio.
CAL多个,CML只有一个
- x:portfolio标准差,y: expected return
- 见方程
- market portfolio, 包含all risky assets, regardless tradable/investible or not
- 图

【risks】
- risk分为
- total variance=
- 公式
- systematic / nonsystematic risk
- total variance=
systematic variance+
nonsystematice variance
【not 标准差】
3.图

Return-Generating Models
4
最后一个加公式
- multi-factor model- macroeconomic/ fundemental/ statistical
- 3-factor, 4-factor
- single-index
- market model
α+βX+e
- single asset β
- portfolio β二种
- 见图
- β=rf+(w1β1+w2β2)[Rm-rf]
β=σp/σm

CAPM模型
6大假设
- investors are risk-averse, u-maximizing, rational
- investors have same expectations, valuation
- investors are price takers
- same single holding period
- market is fractionless, no transaction costs
- all investments are infinitety divisible
security market line SML
- 图形
- 横轴
- 斜率
- 用途2
- 图
- β
- Rm-Rf
- CAPM:确定expected return
判断新的securities 高估还是低估

比较SML&CML
- measure of risk
- applicaition
- slope
- 涵盖的资产
- CML: 只有有效边界上的资产组合
SML:任一资产

【evaluation】
- sharpe ratio等式
- 衡量哪种风险?
- Treynor ration等式
- 衡量哪种风险?
- (Rp-rf)/σp
总风险
- (Rp-rf)/βp
系统性风险
【evaluation】
- M2 公式
衡量哪种风险
- Jensen’s α 两个公式
衡量哪种风险
- =(Rp-rf) αm/αp - (Rm-rf)
total risk
- α=(Rp-rf) - β(Rm-rf)
= Rp - CAPM
系统性风险
4种evaluation方式
什么情况下用什么?
- non-diversified portfolio: 用总体风险
Sharpe ratio, M2
- fully-diversified: 用系统性风险
Treynor ratio, Jensen’s α
security characteristick line
SCL
- 用于什么
- 横纵轴
- 斜率
- 公式
- 纵截距
- 用于单个资产超额收益与market portfolio超额收益之对比
- 横轴:rm-rf
纵轴: ri-rf
- slope: βi
- Ri-rf = α-βi (Rm-rf)
即jensen’s α
- α
【CAPM】limitations
- theoratical 2
- practical 4
- single factor/ single period
- market portfolio:有的资产无法投资
homogeneity in investor expectations假设
beta could be 不准确
CAPM计算结果经常不准确