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Assymetrical Errors

In this video Professor Michael Spagat explains how surveys can dramatically overestimate the prevalence of rare events.

This video clip summarizes a great article by David Hemenway which has two main points:

  1. Survey-based estimates of defensive uses of guns must be too high because they don’t square with other available pieces of evidence.

  2. The article offers a theory, explained in the video, which can explain why these surveys overestimated the prevalence of defensive gun uses by so much. I’m hoping that this theory sounded familiar to you.


What is the connection between Hemenway’s theory and the first 7 steps of this week?

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Survival Statistics: Secrets for Demystifying Numbers

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