¥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