This is Dataplot data file NATR326.DAT Compressive Strength of Concrete (Location Shift Example (with sigma1 not assumed equal to sigma2)) Question: Are the 2 methods the same? Source--Natella, Mary G. (1963). Experimental Statistics. National Bureau of Standards Handbook 91. U.S. Government Printing Office. Page 3-26 to 3-30. Number of observations = 4 + 9 = 13 Number of variables per line image = 2 Order of variables on a line image-- 1. Y1 = Response Variable 1 = Compressive Strength (Method 1) 2. Y2 = Response Variable 2 = Compressive Strength (Method 2) Note--In the data set below, -99 indicates a missing value To read this file into Dataplot-- SKIP 25 READ NATR326.DAT Y1 Y2 DELETE Y1 SUBSET Y1 -99 T TEST Y1 Y2 Y1 Y2 Comp. Strength Comp. Strength Method 1 Method 2 ---------------------------------------- 3128 1939 3219 1697 3244 3030 3073 2424 -99 2020 -99 2909 -99 1815 -99 2020 -99 2310