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Chapter 11: Q. 1 (page 733)

A chi-square goodness-of-fit test is used to test whether a 0 to 9 spinner is "fair" (that is, the outcomes are all equally likely). The spinner is spun 100 times, and the results are recorded. The degrees of freedom for the test will be

(a) 8 .

(c) 10 .

(e) None of these.

(b) 9 .

(d) 99.

Short Answer

Expert verified

(b) The degrees of freedom for the test is9.

Step by step solution

01

Given Information

Need to find the degrees of freedom for the test.

02

Explanation

We have been given a 0 to 9 spinner, which has 10 possible outcomes: 0,1,2,3,4,5,6,7,8,9.

This then implies that there are 10 possible categories for the variables.

c=10

The degrees of freedom for the (chi-square goodness-of-fit) test is then the number of categories decreased by 1.

localid="1650685212354" df=c-1=10-1=9

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