Type I and Type II Errors. In Exercises 29–32, provide statements that identify the type I error and the type II error that correspond to the given claim. (Although conclusions are usually expressed in verbal form, the answers here can be expressed with statements that include symbolic expressions such as p = 0.1.).

The proportion of people who require no vision correction is less than 0.25.

Short Answer

Expert verified

A type I error occurs when the actual value of the proportion is equal to 0.25, and the researcher rejects the claim p=0.25and supports the claim p<0.25.

A type II error occurs when the actual value of the proportion is less than 0.25, and the researcher fails to reject the claim p=0.25.

Step by step solution

01

Given information

It is claimed that the proportion of people who require no vision correction is less than 0.25.

02

Hypotheses

Let p be the population proportion of people who require no vision correction.

According to the stated claim, the following hypotheses are set up:

Null hypothesis H0:p=0.25.

Alternative hypothesis HA:p<0.25.

03

Types of errors

The two types of errors made while conducting hypotheses tests are defined below.

Type I error: Rejecting the null hypothesis when the null hypothesis is true is a type I error and is denoted by α.

Type II error: Failing to reject the null hypothesis when the null hypothesis is false is a type II error and is denoted by β.

In accordance with the given claim, the following statements define the type I error and the type II error:

Type I error: When the actual value of the proportion is equal to 0.25, and the researcher rejects the claim p=0.25and supports the claim p<0.25, a type I error is made.

Type II error: When the actual value of the proportion is less than 0.25, and the researcher fails to reject the claim p=0.25, a type II error is made.

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Most popular questions from this chapter

Cans of coke for the sample data from exercise 1, we get “P-value<0.01” when testing the claim that the new filling process results in volumes with the same standard deviation of 0.115 oz.

  1. What should we conclude about the null hypothesis?
  2. What should we conclude about the original claims?
  3. What do these results suggest about the new filling process?

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