252meanx5 10/13/06 Examples of tests for differences of means————— 10/13/2006 9:27:46 PM ———————————————————— Welcome to Minitab, press F1 for help.MTB > WOpen "C:\Documents and Settings\RBOVE\My Documents\Minitab\252-D.MTW".Retrieving worksheet from file: 'C:\Documents and Settings\RBOVE\MyDocuments\Minitab\252-D.MTW'Worksheet was saved on Fri Oct 13 2006Results for: 252-D.MTWMTB > Print c1 c2Data Display The first data used for Method 1. This was done by method 3.Row D1_1 D1_2 1 305.47 344.53 2 306.48 344.53 3 324.22 344.53 4 334.75 341.47 5 320.61 305.77 6 299.40 298.63 7 299.40 292.51 8 293.34 305.77 9 322.63 389.41 10 294.35 322.09 11 319.60 328.21 12 287.28 361.87 13 290.31 319.03 14 302.43 337.39 15 263.04 291.49 16 307.48 350.65 17 323.64 341.47 18 304.45 369.01 19 310.51 348.61 20 312.53 338.41 21 288.29 309.85 22 307.48 330.25 23 291.32 370.03 24 319.60 327.19 25 328.69 298.63 26 284.25 367.99 27 310.51 293.53 28 314.55 338.41 29 300.41 332.29 30 309.50 341.47 31 303.44 338.41 32 332.73 334.33 33 329.70 329.23 34 321.62 321.07 35 293.34 336.37 36 324.65 348.61 37 322.63 318.01 38 317.58 310.87 39 311.52 319.03 40 311.52 301.69 41 337.78 342.49 42 357.98 344.53 43 291.32 340.45 44 272.13 307.811252meanx5 10/13/06 45 326.67 333.31 46 305.46 326.17 47 277.18 303.73 48 304.45 354.73 49 304.45 342.49 50 320.61 310.87 51 313.54 323.11 52 295.36 339.43 53 315.56 350.65 54 282.23 353.71 55 304.45 303.73 56 270.11 320.05 57 301.42 329.23 58 308.49 315.97 59 331.72 332.29 60 293.34 356.77 61 252.94 312.91 62 316.57 325.15 63 340.81 310.87 64 297.38 324.13 65 307.48 324.13 66 304.45 329.23 67 290.31 348.61 68 304.45 320.05 69 293.34 342.49 70 285.26 346.57 71 303.44 369.01 72 333.74 330.25 73 323.64 305.77 74 280.21 364.93 75 288.29 341.47 76 270.11 321.07 77 264.05 327.19 78 302.43 333.31 79 293.34 331.27 80 274.15 316.99 81 272.13 314.95 82 334.75 336.37 83 277.18 303.73 84 318.59 345.55 85 284.25 318.01 86 303.44 322.09 87 303.44 331.27 88 273.14 336.37 89 273.14 332.29 90 286.27 324.13 91 352.93 318.01 92 274.15 323.11 93 286.27 329.23 94 311.52 327.19 95 292.33 335.35 96 262.03 303.73 97 284.25 313.93 98 311.52 369.01 99 276.17 335.35100 286.27 319.03101 331.72 311.89102 311.52 310.87103 331.72 346.57104 290.31 348.61105 288.29 322.09106 317.58 334.33107 315.56 347.592252meanx5 10/13/06 108 320.61 338.41109 297.38 343.51110 282.23 300.67111 318.59 326.17112 292.33 335.35113 286.27 311.89114 299.40 309.85115 283.24 347.59116 277.18 372.07117 310.51 347.59118 284.25 341.47119 305.46 334.33120 291.32 308.83121 293.34 313.93122 304.45 316.99123 298.39 331.27124 289.30 330.25125 276.17 339.43126 305.46 385.33127 295.36 307.81128 285.26 303.73129 289.30 325.15130 299.40 290.47131 299.40 314.95132 313.54 311.89133 294.35 316.99134 272.13 349.63135 320.61 312.91136 301.42 334.33137 311.52 352.69138 293.34 324.13139 328.69 321.07140 255.97 338.41141 282.23 333.31142 285.26 327.19143 280.21 327.19144 291.32 333.31145 297.38146 268.09147 295.36148 313.54149 275.16150 288.29151 305.46152 281.22153 259.00154 301.42155 291.32156 317.58157 280.21158 284.25159 354.95160 273.14161 319.60162 286.27163 269.10164 292.33165 286.27166 277.18167 313.54168 292.33169 324.653252meanx5 10/13/06 MTB > describe c1 c2Descriptive Statistics: D1_1, D1_2 Variable N N* Mean SE Mean StDev Minimum Q1 Median Q3D1_1 169 0 300.00 1.54 20.00 252.94 286.27 299.40 313.54D1_2 144 0 330.00 1.58 18.98 290.47 316.99 329.74 341.47Variable MaximumD1_1 357.98D1_2 389.41MTB > TwoSample c1 c2. Two-Sample T-Test and CI: D1_1, D1_2 Two-sample T for D1_1 vs D1_2 N Mean StDev SE MeanD1_1 169 300.0 20.0 1.5D1_2 144 330.0 19.0 1.6Difference = mu (D1_1) - mu (D1_2)Estimate for difference: -30.006995% CI for difference: (-34.3481, -25.6657)T-Test of difference = 0 (vs not =): T-Value = -13.60 P-Value = 0.000 DF = 307MTB > print c3 c4Data Display The data in the second example for method 1.Row D1_3 D1_4 1 15.752 21.132 2 19.680 20.281 3 20.662 25.458 4 17.716 18.581 5 21.644 20.281 6 15.752 17.728 7 16.734 22.834 8 20.662 25.387 9 16.734 20.281 10 17.716 20.281 11 19.680 20.281 12 24.590 13.473 13 21.644 22.834 14 17.716 27.940 15 13.788 19.430 16 16.734 21.983 17 17.716 23.685 18 21.644 18.579 19 15.752 20.281 20 24.590 28.791 21 17.716 21.983 22 14.770 10.920 23 11.824 20.281 24 17.716 16.026 25 24.590 28.791 26 23.608 21.132 27 18.698 24.536 28 18.698 19.430 29 18.698 22.834 30 19.680 27.940 31 21.644 25.387 32 13.788 25.3874252meanx5 10/13/06 33 14.770 13.473 34 23.608 19.430 35 21.644 22.834 36 17.716 16.877 37 18.698 38 18.698 39 20.662 40 21.644 41 13.788 42 16.734 43 16.734 44 19.680 45 14.770 46 16.734 47 16.734 48 12.806 49 14.770 50 23.608 51 12.806 52 20.662 53 17.716 54 17.716 55 24.590 56 15.752 57 15.752 58 21.644 59 19.680 60 19.680 61 21.644 62 19.680 63 18.698 64 16.734 65 8.878 66 20.662 67 14.770 68 12.806 69 18.698 70 17.716 71 20.662 72 16.734 73 22.626 74 12.806 75 15.752 76 20.662 77 20.662 78 19.680 79 23.608 80 17.716 81 11.824 82 16.734 83 24.590 84 22.626 85 18.698 86 17.716 87 17.716 88 20.662 89 17.716 90 14.770 91 17.716 92 16.734 93 22.626 94 22.626 95 17.7165252meanx5 10/13/06 96 14.770 97 20.662 98 17.716 99 13.788100 15.752101 21.644102 12.806103 19.680104 12.806105 17.716106 21.644107 20.662108 19.680109 17.716110 18.698111 21.644112 13.788113 13.788114 21.644115 13.788116 22.626117 17.716118 21.644119 18.698120 18.698121 14.770MTB > TwoSample c3 c4;SUBC> Alternative -1.Two-Sample T-Test and CI: D1_3, D1_4 Two-sample T for D1_3 vs D1_4 N Mean StDev SE MeanD1_3 121 18.40 3.30 0.30D1_4 36 21.30 4.20 0.70Difference = mu (D1_3) - mu (D1_4)Estimate for difference: -2.8991795% upper bound for difference: -1.62189T-Test of difference = 0 (vs <): T-Value = -3.81 P-Value = 0.000 DF = 48MTB > print c5 c6
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