# Examples of T-Tests Using Class Data

All the examples on this page compare males and females in my 1998 class. Please note that all calculations are performed using Microsoft Excel, and that the t-statistics are looked up on a t-table rather than a normal table, which is a good thing to do for small samples (e.g., less than 100 cases).

 GPA Females Males Mean 3.22 2.85 Var 0.06 0.11 Obs 27.00 6.00 df 6.00 t Stat 2.66 P(T<=t) two-tail 0.04 t Critical two-tail 2.45

 WORK Females Males Mean 1.85 1.83 Var 0.36 0.57 Obs 27.00 6.00 df 6.00 t Stat 0.06 P(T<=t) two-tail 0.96 t Critical two-tail 2.45

 STUDY Females Males Mean 16.85 13.25 Var 43.25 44.98 Obs 27.00 6.00 df 7.00 t Stat 1.19 P(T<=t) two-tail 0.27 t Critical two-tail 2.36

 ALCOHOL Females Males Mean 7.69 18.67 Var 40.92 151.07 Obs 27.00 6.00 df 6.00 t Stat -2.12 P(T<=t) two-tail 0.08 t Critical two-tail 2.45

 GO OUT Females Males Mean 2.56 3.17 Var 0.74 1.77 Obs 27.00 6.00 df 6.00 t Stat -1.08 P(T<=t) two-tail 0.32 t Critical two-tail 2.45

 HEIGHT Females Males Mean 5.41 5.94 Var 0.04 0.06 Obs 27.00 6.00 df 6.00 t Stat -4.93 P(T<=t) two-tail 0.00 t Critical two-tail 2.45

 WEIGHT VERBAL MATH Females Males Females Males Females Males Mean 126.08 164.67 Mean 530.00 513.33 Mean 591.92 618.33 Var 222.24 474.67 Var 3920.00 7346.67 Var 4560.15 2696.67 Obs 25.00 6.00 Obs 26.00 6.00 Obs 26.00 6.00 df 6.00 df 6.00 df 9.00 t Stat -4.11 t Stat 0.45 t Stat -1.06 P(T<=t) two-tail 0.01 P(T<=t) two-tail 0.67 P(T<=t) two-tail 0.32 t Critical two-tail 2.45 t Critical two-tail 2.45 t Critical two-tail 2.26 EXTRO SENSE THINK Females Males Females Males Females Males Mean 41.85 28.33 Mean 48.41 60.00 Mean 67.22 57.50 Var 554.13 576.67 Var 301.17 1130.00 Var 394.87 567.50 Obs 27.00 6.00 Obs 27.00 6.00 Obs 27.00 6.00 df 7.00 df 6.00 df 7.00 t Stat 1.25 t Stat -0.82 t Stat 0.93 P(T<=t) two-tail 0.25 P(T<=t) two-tail 0.44 P(T<=t) two-tail 0.38 t Critical two-tail 2.36 t Critical two-tail 2.45 t Critical two-tail 2.36 JUDGE Females Males Mean 27.85 57.50 Var 328.05 317.50 Obs 27.00 6.00 df 7.00 t Stat -3.68 P(T<=t) two-tail 0.01 t Critical two-tail 2.36