ink wrote:
Consider these two outcomes
Outcome 1: it offers a return of 10% and a SD of return of 20%
Outcome 2: it offers a return of 12% and a SD of return of 20%
Outcome 2 dominates the outcome 1, because you can earn more return for the same level of risk. Think of all the portofolios under the mean variance frontier; the portofolios above strictly dominate the portofolios below the efficient frontier. (If you choose to select outcome 1, please contact me ASAP, because I would like to engage in some swaps trading withyou

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Now consider this scenario
Outcome 1: it offers a return of 10% and SD of return of 20%
Outcome 2: it offers a return of 10% and SD of return of 10%
In this case, you can’t say that outcome 2 dominates outcome 1. A risk seeking investor might think that a high SD is preferable over a low SD. This is not a case of outcome 2 strictly dominating outcome 1.