Statistical power, definition and levers
A test of against fails to reject at the 5% level, and a colleague concludes the effect doesn't exist.
Define statistical power, compute it for a concrete example, observations, known , true mean , one-sided , and list the levers that increase it.
Show a hint
Power is a probability computed under the alternative. Write the rejection region in terms of , then ask how likely is to land there when .
Your answer
This one is open-ended. Work it through, then check your reasoning against the full solution.