An experiment was conducted to study the extrusion process of biodegradable packaging foam. Two of the factors considered for their effect on the unit density (mg>ml) were the die temperature (145 °C vs. 155 °C) and the die diameter (3 mm vs. 4 mm). The results are stored in PackagingFoam1.

Source: Data extracted from W. Y. Koh, K. M. Eskridge, and M. A. Hanna, “ Supersaturated Split-Plot Designs,” Journal of Quality Technology, 45, January 2013, pp. 61–72.

At the 0.05 level of significance,

a. is there an interaction between die temperature and die diameter?

b. is there an effect due to die temperature?

c. is there an effect due to die diameter?

d. Plot the mean unit density for each die temperature for each die diameter.

e. What can you conclude about the effect of die temperature and die diameter on mean unit density?