1. Do you know population SD? Use Z Test Are there only 2 groups to
Yes No
Use Z
Test
Are there only
2 groups to
Compare?
Yes -
Only 2
No -
More than 2

2. No - More than 2 Groups Yes - Only 2 Groups Use ANOVA If F not
Do you have
Independent data?
If F not
Significant,
Retain Null
If F is
Significant,
Reject Null No
Yes

3. If F not Significant, Retain Null If F is Significant, Reject Null No
Do you have
Independent data?
If F not
Significant,
Retain Null
If F is
Significant,
Reject Null No
Yes
Compare Means
With Multiple
Comparison Tests
Use
Independent
Sample
T test
Use Paired
Sample
T test

4. Use
Independent
Sample
T test
Use Paired
Sample
T test
Is t test
Significant?
Yes No
Compare
means
Reject
Null
Hypothesis
Retain
Null
Hypothesis