introduction to analysis of variance

Question 1

analysis of variance (ANOVA)

Answer 1

a hypothesis-testing procedure used to determine if mean differences exist for two or more treatments or populations (measured by the F-ratio)

Question 2

components of variability

Answer 2

between-treatments variability and within-treatments variability

Question 3

error term

Answer 3

the denominator of the F-ratio; provides a measure of the variance due to chance

Question 4

factor

Answer 4

independent variable

Question 5

levels

Answer 5

individual treatment conditions that make up a factor

Question 6

post hoc tests

Answer 6

methods of determining whether to conclude that means differ significantly (examples: Tukey’s HSD and the Scheffe test)

Question 7

assumptions of ANOVA

Answer 7

(1) observations within each sample are independent, (2) populations from which the samples are selected are normal, (3) populations from which the samples are selected have equal variances