Understanding Main and Interaction Effects
The first part of this book described the principles underlying experimental design and the associated statistical analyses. The second part focuses on the practical aspects of conducting experiments. Understanding the underlying principles is essential to conduct a successful study. In addition it is helpful to know how to put those principles into practice in an efficient manner that is respectful and beneficial to the different stakeholders.
This chapter focuses on recognizing different effects in the results and using the correct terminology to describe them. Both main and interaction effects are systematically introduced for studies with one, two and three independent variables. Main effects can be found in studies with one or more independent variables. Interaction effects can be found in studies with two or more independent variables.
KeywordsInteraction Effect Irritable Bowel Syndrome Average Score Veteran Affair Facial Recognition
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