STAT423/523 HW3

Description

1. (Chapter 10, Section 10.1, Exercise 6. “Origin of Precambrian Iron Formations”) Carry out the ANOVA to investigate if the average Fe percentage for any of the four iron formations is different.

   1. How many treatments are there? How many replications for each treatment?

1. 2. State the null and alternative hypothesis for the average Fe percentage for any of the four iron formations.

1. 3. Construct the ANOVA table using the summary statistics provided below. (You can also use R software. The dataset “iron” is on blackboard.)

An experiment was run to compare = types of boxes (treatment) with respect to

compression strength. Each treatment is replicated 7 times.

a. Complete the ANOVA table by filling in the blanks with the correct values.

Source	Df	SS	MS	F	P-Value
Treatment			0.0668

Total

b. Let i be the true average compression strength for box type = 1, 2, 3. Construct the

Tukey’s interval for each pair of the i- j. Use the
	Treatment	Mean
sample mean from the table.
	1	̅ = 21.714
		1.
	2	̅ = 21.525
		2.
	3	̅ = 21.750
		3.
	Total	̅= 21.682
		..

3. Apply the T Method and draw the underscore plot for comparing the treatments. Briefly explain your results.