Exhibit 11-4
When individuals in a sample of 150 were asked whether or not they supported capital punishment, the following information was obtained.
We are interested in determining whether or not the opinions of the individuals (as to Yes, No, and No Opinion) are uniformly distributed.
-Refer to Exhibit 11-4. The number of degrees of freedom associated with this problem is
A)150
B)149
C)2

Question

Exhibit 11-4
When individuals in a sample of 150 were asked whether or not they supported capital punishment, the following information was obtained.
  We are interested in determining whether or not the opinions of the individuals (as to Yes, No, and No Opinion) are uniformly distributed.
-Refer to Exhibit 11-4. The number of degrees of freedom associated with this problem is
A)150 
B)149 
C)2

Quizplus · Accepted Answer

To test for uniform distribution, we use the chi-square goodness-of-fit test which requires calculating the expected frequency for each category under the assumption of a uniform distribution. Since this involves estimating the parameter of the distribution (in this case, the probability of each category), we lose one degree of freedom. Additionally, we lose one degree of freedom for each category we test (in this case, three categories). Therefore, the number of degrees of freedom for this problem is 3 - 1 = 2, option C.

Exhibit 11-4 When Individuals in a Sample of 150 Were Asked Whether