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Casio fx-CG50 field manual for IB Math

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Two-sample t-test

Maths AI

Run a two-sample t-test on two sets of summary statistics to compare two population means.

Goal

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​.

1

From the MAIN MENU, open Statistics. If you're already inside another app, press first to get back to MAIN MENU.

2

Press (TEST), then (t), then (2-Sample) to open the two-sample t-test wizard.

3

Press (Var) to switch Data from List to Variable, since you have summary statistics. Set the alternative μ1 to ≠μ2, enter both groups' statistics, and set Pooled to On: the IB two-sample ​t​-test assumes the two populations have equal variances, so you pool the sample variances.

RadNorm2
d/cReal
2-Sample tTest
Data:Variable
μ1:≠μ2
x̄1:62.3
sx1:8.1
n1:12
x̄2:57.8
↓
CALCDRAW
4

Move down to Execute and press .

Result

​t≈1.48​ and ​p≈0.152, so at the 5% level there is insufficient evidence of a difference between the means.

RadNorm2
d/cReal
2-Sample tTest
μ1≠μ2
t=1.48004057
p=0.15187087
df=24
x̄1=62.3
x̄2=57.8
↓

Your turn

Work each one on your calculator, then check the answer.

  1. 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. 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. 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.