An article in the Journal of Strain Analysis (Vol. 18, No. 2, 1983) reports a comparison of several methods for predicting the shear strength for steel plate girders. Data for two of these methods, the Karlsruhe and Lehigh procedures, when applied to nine specific girders, are shown below. We wish to determine whether there is any difference between the two methods. Determine which type of test you need (two sample or paired), motivate your choice and discuss any statistical assumptions that you have made in carrying out the analysis, and whether the assumptions seem reasonable. Do the test by hand (report p-value) and use JMP to check your results (paste the JMP output and result in your solution). Finally, formulate your conclusion.
Girder Karlsruhe Method Lehigh Method
S1/1 1.186 1.061
S2/1 1.151 0.992
S3/1 1.322 1.063
S4/1 1.339 1.062
S5/1 1.2 1.065
S2/1 1.402 1.178
S2/2 1.365 1.037
S2/3 1.537 1.086
S2/4 1.559 1.052