ANOVA Is Simply an Analysis of Variance

ANOVA is simply an analysis of variance measure in statistics that is used to compare the means, or average, of more than two groups. It tests for significant differences, or differences that are large enough to effect or change the study outcomes. It analyzes variances between and within the study groups and can test several null hypothesis, or claims being tested, at the same time. It is also used to compare the variances between the group members as well as between the individual sample groups.

The one way ANOVA is used to compare a single factor in more than two groups. It also is used to determine relationships within a group and the correlation of the factor among group members over time. The ANOVA is performed at intervals of the study to determine how the factor changes and the degree it changes in the given study timeframe.

The two way ANOVA is used to analyze a single factor (dependent variable) based on two other factors (independent variables). The two way ANOVA can show the effect of the one factor after controlling for another, or the interaction between the factors. It does not necessarily require the same number of subjects in each group.

ANOVA is an attempt to determine if significant differences are present between groups and within groups. It can be ran at intervals over time to answer particular questions in research studies. ANOVA ran at intervals over time help researchers see differences in data over a particular timeframe that can show discoveries.

Interaction

An interaction is the effect that one or more factors, independent variables, has on another factor, dependent variable. For example, suppose you want to test whether gender has an effect on the average time a pain reliever takes effect, whether the type of medication has an effect on the average time a pain reliever takes effect, and if there is interaction effect between gender and type of medication on the average time a pain reliever takes effect. The dependent variable would be the average time a pain reliever takes effect where the independent variables are gender and type of medication.