(a) Rework part (b) of Problem 3-1 using Duncan's multiple range test with = 0.05. Does...

(a) Rework part (b) of Problem 3-1 using Duncan's multiple range test with α = 0.05. Does this make any difference in your conclusions?

(b) Rework part (b) of Problem 3-1 using Tukey's test with α = 0.05. Do you get the same conclusions from Tukey's test that you did from the graphical procedure and/ or Duncan's multiple range test?

(c) Exnlain the difference between the Tukey and Duncan procedures.

Problem 3-1

The tensile strength of portland cement is being studied. Four different mixing techniques can be used economically. The following data have been collected:

 

Transcribed Image Text:

Mixing Technique Tensile Strength (lb/in?) 1 3129 3000 2865 2890 2 3200 3300 2975 3150 2800 2900 2985 3050 4 2600 2700 2600 2765