We are given data on the extroversion levels of students in four different majors: English, History, Psychology, and Math. We want to perform an ANOVA test to determine if there is a significant difference in extroversion levels between the majors. We are given the sample means for each major ($\bar{X}_1 = 3.67, \bar{X}_2 = 3.02, \bar{X}_3 = 5.10, \bar{X}_4 = 3.47$), the sample sizes for each major ($n_1 = 60, n_2 = 44, n_3 = 21, n_4 = 60$), the between-groups sum of squares ($SS_B = 62.92$), the within-groups sum of squares ($SS_W = 1943.06$), and the significance level ($\alpha = 0.05$). We need to calculate the F-statistic and determine if it is significant.
2025/4/23
1. Problem Description
We are given data on the extroversion levels of students in four different majors: English, History, Psychology, and Math. We want to perform an ANOVA test to determine if there is a significant difference in extroversion levels between the majors. We are given the sample means for each major (), the sample sizes for each major (), the between-groups sum of squares (), the within-groups sum of squares (), and the significance level (). We need to calculate the F-statistic and determine if it is significant.
2. Solution Steps
First, we need to calculate the degrees of freedom.
The degrees of freedom between groups () is the number of groups minus
1.
, where is the number of groups.
The degrees of freedom within groups () is the total sample size minus the number of groups.
, where is the total sample size.
Next, we calculate the mean square between groups () and the mean square within groups ().
Now, we can calculate the F-statistic.
We are given . We need to find the critical F-value with and . Since 181 is not a common value in F-tables, we can approximate using 120 or 200 degrees of freedom. Using an online F-distribution calculator, the critical F-value for , and is approximately .
Since our calculated F-statistic () is less than the critical F-value (), we fail to reject the null hypothesis.
3. Final Answer
Fail to reject the null hypothesis.