¥Two-Way ANOVA
HPurpose: To test for the
effects of two factors on the measurements
åi.e., drug type for factor 1
and drug dosage for factor 2
åor drug dosage for factor 1
and subject for factor 2
HSame statistics as one way
ANOVA for each of the 2 factors
åfactor effect
åfactor mean, difference and
contrasts
HStatistics for factor
interactions
åwhen the effect of factor A
depends on the level of factor B and vice-versa
HOptions for using fixed,
random and mixed effect models
åFixed models:
íTesting for differences in means
between factors
íHypothesis testing applies
only to treatments explicitly considered.
íi.e. if dose levels of 5 mg,
15 mg and 25 mg are used for treatments, we cannot make a statement about effects of
dose levels of 2 mg or 100 mg