[amp_mcq option1=”s hat r” option2=”r bar s” option3=”r hat s” option4=”s bar r” correct=”option2″]
The correct answer is $\boxed{\text{A}}$.
The after-the-fact rate of return, often considered as realized or actual, can be denoted as $\hat{r}_s$. This is because the superscript $\hat{*}$ is used to denote a realized or actual value, and the subscript $s$ denotes the security.
The other options are incorrect because:
- Option $\text{B}$, $r_{\bar{s}}$, is the expected rate of return.
- Option $\text{C}$, $r_{\hat{s}}$, is the ex ante rate of return.
- Option $\text{D}$, $s_{\bar{r}}$, is the standard deviation of the return.