STAT 301 LabLab 9: Two-Way ANOVAT.A.: Yixuan QiuWhat's Two-way ANOVA?- The purpose is similar to One-way ANOVA, but now we have two factors. - Example: Is the amount of weekly physical activity of college students different inthree states for male and female?- Two factors: state, gender. What we want to test?- Main effect- Will the state influence the amount?- Will gender influence the amount?- Is the influence of state the same for male and female? How do you know whether there is interaction?- If any lines cross each other, then you have an interaction.- If the lines are all fairly parallel to each other, then you do not have an interaction.- If the lines aren't parallel but don't cross each other either, then you might have an interaction. Check the assumption- Need independent SRSs- Population should be Normal with the same standard deviation- Largest std. < 2 * smallest std.Interpret the result