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Macro· 4:02 runtime

The Efficient Markets Hypothesis, why that bargain on your screen probably is not one

Why prices already reflect public information, why only new and unpredictable news moves them, and why consistently beating the market is so hard.

Macro· 4:02

The Efficient Markets Hypothesis, why that bargain on your screen probably is not one

Why prices already reflect public information, why only new and unpredictable news moves them, and why consistently beating the market is so hard.

InteractiveExplore The Efficient Markets Hypothesis in the Atlas

A 4 minute 2 second animated lesson on the efficient markets hypothesis, the idea that asset prices already reflect the information available to traders. Built for students of money, banking and financial markets, and for anyone weighing whether a stock is really a bargain.

The video starts with a stock at one hundred dollars that you are sure is worth one hundred and ten. The hypothesis explains why that easy profit is unlikely to last. If the information were public, other traders would already have acted on it and moved the price, so what is left to move prices is genuine surprise, which by definition cannot be predicted. That is why returns look close to a random walk and why beating the market consistently is so hard.

It closes on what efficiency does and does not claim. Prices reflect available information, which is not the same as prices always being right, so bubbles and mistakes are still possible. The weak, semi strong and strong forms simply widen the set of information assumed to be in the price. Pair the video with the Atlas concept page for the intuition, misconceptions, a quick quiz and citations.

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The Efficient Markets Hypothesis
Formulas, worked examples, common mistakes, and a quick check quiz — open the concept page for the full Atlas treatment.
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