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Types of Errors and Power

Types of Errors and Power

Author: Al Greene

• Review how to use level of significance (α) and critical values to determine statistical significance
• Discuss the concept of Type I (α )and Type II (β) Errors
• Discuss the concept of Power (1 – β)
• Discuss how to reduce type I and type II errors

This packet introduces you to types of error of a statistical test. There are type I and type II error, as well as the power of a test. We discuss how to find them, how to reduce them, and how to use them to determine statistical significance.

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What's in this packet

This packet brings up types of error. We have a slideshow discussing the two types of error, as well as power. We also have examples of each, and links to other sites talking about power and error in other fields. Some new terms in this packet are:

  • Level of Significance
  • Critical Values
  • Type I Error
  • Type II Error
  • Power

Source: Greene

Types of Error

This presentation talks about the two types of error, as well as power of a test.

Source: Greene

What is Statistical Power?

This video is a podcast talking about statistical power and type II error.

Error and the Courts

This link has an amazing example illustrating error and power in the court systems, and the ramifications of each.