The SAS System        22:14 Thursday, August 25, 2011   1

                                       Obs    method    score

                                         1     STD        79
                                         2     STD        73
                                         3     STD        72
                                         4     STD        62
                                         5     STD        76
                                         6     STD        68
                                         7     STD        70
                                         8     STD        86
                                         9     STD        75
                                        10     STD        68
                                        11     STD        73
                                        12     STD        66
                                        13     NEW        70
                                        14     NEW        85
                                        15     NEW        80
                                        16     NEW        76
                                        17     NEW        80
                                        18     NEW        66
                                        19     NEW        71
                                        20     NEW        79
                                        21     NEW        81
                                        22     NEW        76

                                           The SAS System        22:14 Thursday, August 25, 2011   2

                                        The TTEST Procedure

                                          Variable:  score

           method          N        Mean     Std Dev     Std Err     Minimum     Maximum

           NEW            10     76.4000      5.8348      1.8451     66.0000     85.0000
           STD            12     72.3333      6.3437      1.8313     62.0000     86.0000
           Diff (1-2)             4.0667      6.1199      2.6204

   method        Method               Mean       95% CL Mean        Std Dev      95% CL Std Dev

   NEW                             76.4000     72.2261  80.5739      5.8348      4.0134  10.6520
   STD                             72.3333     68.3027  76.3639      6.3437      4.4938  10.7708
   Diff (1-2)    Pooled             4.0667     -1.3994   9.5327      6.1199      4.6821   8.8376
   Diff (1-2)    Satterthwaite      4.0667     -1.3601   9.4934

                    Method           Variances        DF    t Value    Pr > |t|

                    Pooled           Equal            20       1.55      0.1364
                    Satterthwaite    Unequal      19.769       1.56      0.1336

                                       Equality of Variances

                         Method      Num DF    Den DF    F Value    Pr > F

                         Folded F        11         9       1.18    0.8148