Zusammenfassung der Ressource
Portfolio Construction
- CAPM
Anmerkungen:
- Capital Asset Pricing Model
- E(R) = Rf + b [E(Rm) - Rf]
Anmerkungen:
- Rf is risk free return
E(Rm) expected return of market
b is beta
- assumptions
- rational decisions
- risk
- return
- identical time horizon/holding period
- many buyers and sellers
- no single investor affects prices
- no taxes or transaction costs
- information is free/available to all investors
- money can be deposited/borrowed at risk-free rate
- all investments are liquid/divisible
- investors are buying diversified portfolios of shares
- limitations
- demanding assumptions
- assumes price solely determined by relationship to market (beta)
- appears other factors also influence return
- not a historically reliable predictor of return
- beta calculations
- use historic data
- not stable
- not accurate prediction of future beta
- risk-free return difficult to identify
- short-term government paper
- UK/USA credit downgrades
- risk measures
- standard deviation
- beta
- Jensen's alpha
- correlation
- efficient frontiers
- portfolio construction
- problems
- multi-factor models