Question

Consider the following summary data on the modulus of elasticity ( 106 psi) for lumber of three different grades. Grade J Xi. Si 1 11 1.62 0.23 11 1.61 0.22 11 1.54 0.25 Use this data and a significance level of 0.01 to test the null hypothesis of no difference in mean modulus of elasticity for the three grades. Calculate the test statistic. (Round your answer to two decimal places.) f= What can be said about the p-value for the test? O P-value > 0.100 0 0.050 < P-value < 0.100 O 0.010 < P-value < 0.050 O 0.001 < P-value < 0.010 O P-value < 0.001 What can you conclude? O Reject Ho. At least two of the three grades appear to differ significantly Reject Ho. The three grades do not appear to differ significantly. Fail to reject Ho. The three grades do not appear to differ significantly. Fail to reject Ho. At least two of the three grades appear to differ significantly. You may need to use the appropriate table in the Appendix of Tables to answer this question.

Answer 1

Sol:

Ho:all the 3 groups are equal

Ha:atleast one of the group means are different

MS F F crit ANOVA Source of Variation SS Between Groups Within Groups df 0.042 1.638 P-value 0.383 0.685 2 0.021 0.055 30 Total 1.68 32

alpha=0.01

F=0.38

P-value>0.100

Fail to reject Ho.The three grades do not appear to differ significantly