10. Quiz: Types of Errors - Part II(a)

Types of Errors

This is frequently the part of hypothesis testing that begins to get confusing. There are multiple names used to describe the same thing. Let's recap some of the most important ideas and give you some practice answering questions about each.

Use the below to identify each of the possible types of errors.

A type I error is one in which

SOLUTION: we believe the alternative to be true, but in reality the null is true.

A type II error is one in which

SOLUTION: we believe the null to be true, but in reality the alternative is true.

The above two definitions fully specify the definitions of Type I and Type II errors. For any set of competing hypotheses, you can now identify what the specific Type I and Type II errors would be for that situation.

Below you will identify type I and type II errors according to the Greek symbols that are frequently used to represent each.

What notation is most frequently used to denote a type I error rate?

SOLUTION: alpha

What notation is most frequently used to denote a type II error rate?

SOLUTION: beta

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