Good Day,
I am new to the site, the layout is great, nice to see a Minitab forum.
I am exploring a problem involving test for equal variances (TEV)...as part of a Two Way ANOVA; two factors both factors have three levels...all conducted with Minitab 15.,
My dilemma is this, when I run the TEV three ways, each factor alone & then together; each factor alone confirms equal variances, yet both factors together the Bartletts and Levene's test are p = 0.000 & 0.002 respectively or evidence of unequal variances. When a Two Way ANOVA is run, a statistically significant difference in means is revealed for factor 2.
Simply put is the result of the two factor TEV of concern? If, so what? Again my goal is to evaluate whether there is a statistically significant difference in means relative to my process output, diameter, via a Two Way ANOVA.
Thank you in advance for your assistance....
I am new to the site, the layout is great, nice to see a Minitab forum.
I am exploring a problem involving test for equal variances (TEV)...as part of a Two Way ANOVA; two factors both factors have three levels...all conducted with Minitab 15.,
My dilemma is this, when I run the TEV three ways, each factor alone & then together; each factor alone confirms equal variances, yet both factors together the Bartletts and Levene's test are p = 0.000 & 0.002 respectively or evidence of unequal variances. When a Two Way ANOVA is run, a statistically significant difference in means is revealed for factor 2.
Simply put is the result of the two factor TEV of concern? If, so what? Again my goal is to evaluate whether there is a statistically significant difference in means relative to my process output, diameter, via a Two Way ANOVA.
Thank you in advance for your assistance....