ANOVA Basics
1.Similar
to t-test Ð except IV has 2 or more levels
2.One-Way
n1 IV analyzed and 1
DV measured
nH0: population means are all equal (H0: µ1 = µ2 = µ3)
nH1: population means are NOT equal (µ1 µ2 µ3)
nTreatment Ð may have
more than 2 levels
3.Hypothesis
testing
nH0 (null) and
H1 (alternate) hypotheses are stated (Assume H0 is
true)
nSampling
distribution Ð t or F
nGather data and
calculate F value
nCompare calculated F to table
value and Interpret results
4.F
distribution
nF is a sampling
distribution (just as t distribution is)
nRatio Ð
treatment/between groups variation to within group variation
¤B - between groups Ð do groups differ due to
treatment
¤W or E within (error) Ð unbiased estimate of variability
in same group
¤B > W reject Ho (treatment had effect)
¤Small variability (F=1.00) Ð keep H0, large var (F > 1.00) Ð reject H0