In the design of experiments and analysis of variance, a

**main effect**is the**effect**of an independent variable on a dependent variable averaging across the levels of any other independent variables.Regarding this, what is a main effect and an interaction effect?

Understanding

**Main Effects**and**Interactions**. A**main effect**is the**effect**of a single independent variable on a dependent variable – ignoring all other independent variables. For example, imagine a study that investigated the effectiveness of dieting and exercise for weight loss.What does a significant interaction mean?

When an

**interaction**effect is present, the impact of one factor depends on the level of the other factor. Part of the power of ANOVA**is the**ability to estimate and test**interaction**effects. When**interaction**effects are present, it**means**that interpretation of the main effects is incomplete or misleading.What is the main effect in psychology?

A 2 x 2 x 2 factorial design is a design with three independent variables, each with two levels.

**Main Effects**. A “**main effect**” is the**effect**of one of your independent variables on the dependent variable, ignoring the**effects**of all other independent variables.