Mood swings and irrational behavior used to be called simply that: mood swings and irrational behavior.

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If the above average effect holds up for groups, it might explain a lot of irrational behavior.

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Then we take advantage of this behavior, this often temporary irrational behavior, by buying company stock before other investors adjust their prior expectations to reflect those new fundamentals.

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Irrational behavior is part of the human condition.

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So just how irrational is his behavior?

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Whether that human economic behavior is rational or irrational may ultimately be a matter of perspective.

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