State three null and alternative hypotheses for this study (test for Brand, Temp, and the Brand* Temp interaction). Conduct an ANOVA to analyze the Popcorn data. Even though storage temperature is crossed with Box (a nuisance factor), this interaction effect is of no interest and typically is not shown in an ANOVA table. Check the normality assumption and for equal variances.
Create a main effects plot and interaction plot for Brand and Temp using the Popcorn data. Which Brand and which Temp appeared to do better? Even though the graph appears to show a difference between levels, only p- values can determine if differences are significant. In other words, p-values tell us how often we would expect effect sizes at least this large in a random sample if there really was no difference in Brand levels. State your conclusions for all three hypotheses.