A researcher is interested in whether there is a significant difference between the mean age of marriage across three racial groups. Based on the data below, the mean square between and the mean square within are 313.01 and 36.87, respectively. Calculate the [tex]$F$[/tex] statistic.

\begin{tabular}{|l|l|l|}
\hline Race & N & Mean \\
\hline Black & 113 & 25.39 \\
\hline White & 904 & 22.99 \\
\hline Other & 144 & 23.87 \\
\hline All groups & 1,161 & 23.33 \\
\hline
\end{tabular}



Answer :

To determine if there is a significant difference between the mean age of marriage across the three racial groups, we use an Analysis of Variance (ANOVA). The ANOVA test involves calculating the F statistic, which compares the mean square between the groups to the mean square within the groups.

Here's the step-by-step solution to calculate the F statistic:

1. Identify the given values:
- Mean square between groups ([tex]\(MS_{between}\)[/tex]): 313.01
- Mean square within groups ([tex]\(MS_{within}\)[/tex]): 36.87

2. Calculate the F statistic:
- The formula for the F statistic in ANOVA is:
[tex]\[ F = \frac{MS_{between}}{MS_{within}} \][/tex]

3. Insert the given values into the formula:
- Substitute [tex]\(MS_{between} = 313.01\)[/tex] and [tex]\(MS_{within} = 36.87\)[/tex] into the formula:
[tex]\[ F = \frac{313.01}{36.87} \][/tex]

4. Compute the result:
- Performing the division gives:
[tex]\[ F \approx 8.49 \][/tex]

Hence, the F statistic is approximately 8.49.

In summary, the calculations show that the F statistic value, which allows us to determine if the variances between groups are significantly different from the variances within groups, is approximately 8.49. This value can then be compared to a critical value from the F-distribution table to make a decision regarding the null hypothesis.