Determine the results of the One-way ANOVA test for the sales data of different cereal box shapes.
Calculate \(SS_{between}\).
The sum of squares between groups is calculated as follows:
\[
SS_{between} = \sum_{i=1}^k n_i (\bar{X}_i - \bar{X})^2 = 4911.75
\]
Calculate \(SS_{within}\).
The sum of squares within groups is calculated as follows:
\[
SS_{within} = \sum_{i=1}^k \sum_{j=1}^{n_i} (X_{ij} - \bar{X}_i)^2 = 13561.2
\]
Calculate \(MS_{between}\).
The mean square between groups is calculated as:
\[
MS_{between} = \frac{SS_{between}}{df_{between}} = \frac{4911.75}{3} = 1637.25
\]
Calculate \(MS_{within}\).
The mean square within groups is calculated as:
\[
MS_{within} = \frac{SS_{within}}{df_{within}} = \frac{13561.2}{16} = 847.575
\]
Calculate the F-statistic.
The F-statistic is calculated as:
\[
F = \frac{MS_{between}}{MS_{within}} = \frac{1637.25}{847.575} = 1.9317
\]
Calculate the p-value.
The p-value is calculated as:
\[
P = 1 - F(F_{observed}; df_{between}, df_{within}) = 1 - F(1.9317; 3, 16) = 0.1652
\]
The results of the One-way ANOVA test are:
- Degrees of Freedom Between Groups: \(3\)
- Degrees of Freedom Within Groups: \(16\)
- F-Statistic: \(1.9317\)
- P-Value: \(0.1652\)
- Mean Square Between Groups: \(1637.25\)
- Mean Square Within Groups: \(847.575\)
The results indicate that there is no statistically significant difference in mean sales among the different shapes of cereal boxes, as the p-value \(0.1652\) is greater than the significance level \(0.05\).
\(\boxed{\text{No significant difference in mean sales among box shapes.}}\)