Completely Randomized Design:
An article in the ACI Materials Journal states several experiments investigating rodding of concrete to remove entrapped air. A 3" ? 6" cylinder was used, and the number of times this rod was used is the treatment factor. The resulting compressive strength of the concrete specimen is the response. The data are shown in the following table.
|
Rodding Level
|
Compressive Strength
|
Compressive Strength
|
Compressive Strength
|
|
10
|
1530
|
1620
|
1440
|
|
15
|
1500
|
1590
|
1510
|
|
20
|
1710
|
1808
|
1770
|
|
25
|
1730
|
1680
|
1890
|
a. Analyze the above data and draw your conclusions.
b. If appropriate, provide point estimates of all the parameters in this model.