Thursday, February 28, 2019

The limits to investment stories - Better to have a sample of data


I have an anecdote, but not an antidote, for whatever ails you; that is the problem. Stories or tales of past economic events do not solve investment problems. Investment tales may persuade as a device for action. They may provide useful background information, but they do not provide the basis for an effective solution. 

A tale can be a description of a specific event, or it can be a generalization associated with an event. For example, an investment story can be about the Fed Chairman. "I made a lot of money by fading comments by Chairman Powell; he does not have a lot creditability. Look at his last speech." Good story. Maybe true. But, a story is dangerous if it is not backed with data. Extrapolation from a sample of one is not effective decision-making.

Story can be useful but mainly in a case where there is no data set to help with the decision. Narrative is applicable for the unique situation, but only because there are no countable alternatives. Count similar events and focus on the odds not the narrative from one example.  

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