A marketing research firm is conducting a survey to determine if there is a difference in consumer choice in the selection of two rival soft drinks. Those surveyed were asked to rank the taste from 1-10 with 10 being the highest rating. A summary of the survey follows: Calculate the test statistic: A) 2.40
B) -1.52
C) 0
D) -2.1
The number of degrees of freedom associated with the t test, when the data are gathered from a matched pairs experiment with 13 pairs, is: A) 13
B) 26
C) 12
D) 24
Use df = n - 1. You only count the items or subjects once for your sample size in this kind of t-test.
a b
To calculate the test statistic, we need more specific information about the data, such as the means and standard deviations of the two groups. However, based on the given options, we can proceed by eliminating options that are not applicable in this scenario.
The test statistic for comparing the means of two groups is typically computed using a two-sample t-test or a paired t-test, depending on the experimental design. A paired t-test is appropriate when the data are gathered from a matched pairs or within-subjects experiment, where the same participants are measured in both groups.
In this case, the given information states that the data are gathered from a matched pairs experiment with 13 pairs. The degrees of freedom for a paired t-test are equal to the number of pairs minus 1.
Therefore, the correct answer to the second part of the question, regarding the degrees of freedom, is:
C) 12 (13 pairs minus 1).
Please note that without more information about the test statistic itself, we cannot determine the exact answer to the first part of the question.