Two Meanings of Market Efficiency Are Commonly Confused
Statman separates markets where price equals value from markets that are hard to beat. Bubbles disprove the first condition, but their existence does not tell an investor when or how to profit from them.
- Price-equals-value efficiency excludes bubbles
- Hard-to-beat efficiency concerns consistent advantage
- Recognizing bubbles is not the same as timing them
“There are two concepts, two notions of market efficiency there are that are regularly confused.”
“But knowing that you will have bubbles does not mean that you know when they occur when it is time to actually take advantage of…”