Principles of Finance · 免费预览
概率分布与期望值
概率分布为各种结果赋予概率，期望值按结果的概率加权以确定不确定前景的中心趋势，投资组合的期望收益率则是其中各项资产按概率加权的均值。
1. Probability distributions
Probability distributions
2. Expected value, the probability-weighted mean
Expected value, the probability-weighted mean
3. Portfolio expected returns
Portfolio expected returns
4. From scenarios to decisions
From scenarios to decisions
5. The distribution's requirements
Which properties must a probability distribution satisfy?
6. Computing the expected return
A stock has a 20 percent chance of returning 20 percent, a 50 percent chance of 8 percent, and a 30 percent chance of minus 10 percent. What is the expected return?
7. Expected versus most likely
Why can the expected return differ from the most likely return?
8. The portfolio expected return
A portfolio holds 50 percent in a stock expected to return 8 percent and 50 percent in a bond expected to return 4 percent. What is the portfolio's expected return?
9. Linearity's meaning
What does it mean that expectation is linear, and why does it matter for portfolios?
10. The judgment caveat
Why does an expected value based on judgment-assigned probabilities deserve skepticism?
11. The weighted average's name
What two-word term names the probability-weighted average of a distribution's outcomes? Answer in lowercase.
12. The linearity property
What one-word term names the property that the expectation of a weighted sum equals the weighted sum of expectations? Answer in lowercase.
13. The scenario tool's name
What two-word analysis technique builds scenarios with probabilities and computes probability-weighted outcomes to summarize a plan? Answer in lowercase.
14. The portfolio weights sum
A portfolio's asset weights, expressed as fractions, must sum to what number? Write the number.