You discover you can make above normal returns if you buy oil-company stocks just before noon on any given trading day and then sell them immediately before the market closes that same day.
Which of the following describes this event?

Question

Quizplus · Accepted Answer

This strategy of buying oil-company stocks based on a specific time of day suggests that the market may not be weak-form efficient. If the market was weak-form efficient, this strategy would not generate above-normal returns, as past stock prices and patterns would already be reflected in the stock's current price. However, it is possible that the market may still be semi-strong or strong-form efficient.

You Discover You Can Make Above Normal Returns If You