For some data sets, the F statistic will reject the null hypothesis of no difference in
14. In an experiment to determine the effect of curing time on the compressive strength of a certain type of concrete, the mean strengths, in MPa, for specimens cured for each of four curing times were
- a. If MSE = 875.2, compute the value of the F statistic for testing the null hypothesis that all four curing times have the same mean strength. Can this null hypothesis be rejected at the 5% level?
- b. Use the Tukey–Kramer method to determine which pairs of curing times, if any, may be concluded to differ at the 5% level.
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