September 09, 2003

Tables

Sometimes a table is the most convenient way to describe the sample space.

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Posted by bparke at 10:28 AM

Rolling Dice

Rolling two dice is an example of an experiment where listing the complete sample space works well.

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Two dice are physically and statistically independent.

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Some probabilities found by studying the diagram:

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Posted by bparke at 10:12 AM

Bayes' Theorem

Bayes' Theorem is an elegant application of a Venn diagram.

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The proof is algebraic.

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Bayesian statistical analysis uses Bayes' Theorem to think about theta.

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Using Bayes' Theorem to consider the implications of observing two sixes when the dice might be fair or they might have two sixes on each die.

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The practical problem with applying Bayesian analysis in economics is that we do not have a good source for the prior probabilities about theta. What is the probability that Keynes was right?

Posted by bparke at 10:06 AM

Venn Diagrams and Other Representations

A venn Diagram has four pieces of information, and knowing any three allows you to solve for the fourth because the areas add up to one.

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A complete list of possible Venn diagrams:

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Posted by bparke at 10:03 AM