TI-84 Plus CE field manual for IB Math
Two-sample t-test
Run a two-sample t-test on two sets of summary statistics to compare two population means.
Two independent groups score xˉ1=62.3, s1=8.1, n1=12 and xˉ2=57.8, s2=7.4, n2=14. Test H0:μ1=μ2 against Ha:μ1=μ2.
Press , move right to TESTS, and choose 4: 2-SampTTest.
Set Inpt to Stats and enter both groups' summary statistics. Select the alternative μ1=μ2, and set Pooled to Yes: the IB two-sample t-test assumes the two populations have equal variances, so you pool the sample variances.
Move down to Calculate and press .
t≈1.48 and p≈0.152, so at the 5% level there is insufficient evidence of a difference between the means.
Your turn
Work each one on your calculator, then check the answer.
- 1
Group 1: xˉ1=78.4, s1=6.2, n1=15. Group 2: xˉ2=74.9, s2=7.1, n2=18. Test H0:μ1=μ2 against Ha:μ1=μ2 at the 5% level.
- 2
Group 1: xˉ1=12.1, s1=1.8, n1=10. Group 2: xˉ2=13.4, s2=2.2, n2=14. Test H0:μ1=μ2 against Ha:μ1=μ2 at the 5% level.
- 3
Group 1: xˉ1=55.0, s1=10.5, n1=30. Group 2: xˉ2=58.2, s2=9.8, n2=28. Test H0:μ1=μ2 against Ha:μ1=μ2 at the 5% level.