##### research methods chapter 11

factor

is an independent variable in an experiment, especially those that include two or more independent variables.

factorial design

is a research design that includes two or more factors

single-factor design

a research study with only one independent variable.

main effect

the difference between the two columns means

interaction between factors

occurs whenever two factors, acting together, produce mean differences that are not explained by the main effects of the two factors

interaction

exists between the factors when the effects of one factor depend on the different levels of a second factor. indicated by the existence of nonparallel lines.

mixed designs

factorial study that combines two different research designs.

combined strategy

Uses two different research strategies in the same factorial design. one factor is a true independent variable and the other factor is a quasi-independent variable

higher-order factorial design

complex designs involving three or more factors

- No order effects
- symmetrical order effects
- non-symmetrical order effects

using order of treatments as a second factor