• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
The Analysis Factor

The Analysis Factor

Statistical Consulting, Resources, and Statistics Workshops for Researchers

  • our programs
    • Membership
    • Online Workshops
    • Free Webinars
    • Consulting Services
  • statistical resources
  • blog
  • about
    • Our Team
    • Our Core Values
    • Our Privacy Policy
    • Employment
    • Collaborate with Us
  • contact
  • login

effect coding

Member Training: Dummy and Effect Coding

by Karen Grace-Martin  2 Comments

Why does ANOVA give main effects in the presence of interactions, but Regression gives marginal effects?Stage 2

What are the advantages and disadvantages of dummy coding and effect coding? When does it make sense to use one or the other?

How does each one work, really?

In this webinar, we’re going to go step-by-step through a few examples of how dummy and effect coding each tell you different information about the effects of categorical variables, and therefore which one you want in each situation.


Note: This training is an exclusive benefit to members of the Statistically Speaking Membership Program and part of the Stat’s Amore Trainings Series. Each Stat’s Amore Training is approximately 90 minutes long.

Not a Member? Join!

About the Instructor

Karen Grace-Martin helps statistics practitioners gain an intuitive understanding of how statistics is applied to real data in research studies.

She has guided and trained researchers through their statistical analysis for over 15 years as a statistical consultant at Cornell University and through The Analysis Factor. She has master’s degrees in both applied statistics and social psychology and is an expert in SPSS and SAS.

Not a Member Yet?
It’s never too early to set yourself up for successful analysis with support and training from expert statisticians. Just head over and sign up for Statistically Speaking.

You'll get access to this training webinar, 100+ other stats trainings, a pathway to work through the trainings that you need — plus the expert guidance you need to build statistical skill with live Q&A sessions and an ask-a-mentor forum.

Tagged With: categorical variable, dummy coding, effect coding

Related Posts

  • Member Training: The Link Between ANOVA and Regression
  • Member Training: Multinomial Logistic Regression
  • Member Training: Centering
  • Member Training: Missing Data

Interpreting Interactions Between Two Effect-Coded Categorical Predictors

by Karen Grace-Martin  13 Comments

I recently received this great question:

Question:

Hi Karen,  ive purchased a lot of your material and read a lot of your pdf documents w.r.t. regression and interaction terms.  Its, now, my general understanding that interaction for two or more categorical variables is best done with effects coding, and interactions  cont v. categorical variables is usually handled via dummy coding.  Further, i may mess this up a little but hopefully you’ll get my point and more importantly my question, i understand that

1)  given a fitted line Y = b0 + b1 x1 + b2 x2 + b3 x1*x2, the interpretation for b3 is the diff of the effect of x1 on Y, when x2 changes one unit, if x1 and x2 are cont.  ( also interpretation can be reversed in terms of x1 and x2). [Read more…] about Interpreting Interactions Between Two Effect-Coded Categorical Predictors

Tagged With: effect coding, interaction, linear regression

Related Posts

  • Understanding Interactions Between Categorical and Continuous Variables in Linear Regression
  • Using Pairwise Comparisons to Help you Interpret Interactions in Linear Regression
  • Understanding Interaction Between Dummy Coded Categorical Variables in Linear Regression
  • The Difference Between Interaction and Association

Why ANOVA and Linear Regression are the Same Analysis

by Karen Grace-Martin  70 Comments

Stage 2If your graduate statistical training was anything like mine, you learned ANOVA in one class and Linear Regression in another.  My professors would often say things like “ANOVA is just a special case of Regression,” but give vague answers when pressed.

It was not until I started consulting that I realized how closely related ANOVA and regression are.  They’re not only related, they’re the same thing.  Not a quarter and a nickel–different sides of the same coin.

So here is a very simple example that shows why.  When someone showed me this, a light bulb went on, even though I already knew both ANOVA and multiple linear [Read more…] about Why ANOVA and Linear Regression are the Same Analysis

Tagged With: analysis of covariance, analysis of variance, ancova, ANOVA, dummy coding, effect coding, linear regression

Related Posts

  • 3 Reasons Psychology Researchers should Learn Regression
  • SPSS GLM: Choosing Fixed Factors and Covariates
  • The General Linear Model, Analysis of Covariance, and How ANOVA and Linear Regression Really are the Same Model Wearing Different Clothes
  • Why ANOVA is Really a Linear Regression, Despite the Difference in Notation

Concepts in Linear Regression you need to know before learning Multilevel Models

by Karen Grace-Martin  2 Comments

It seems very many researchers are needing to learn multilevel and mixed models, and I have to say, it’s not so easy on your own.

I too went to graduate school before it was taught in classes–we did learn mixed models as in Split Plot designs, but things have progressed a bit since then.  So I too have had to learn them without benefit of a class, or teacher.  So I feel your pain.  But I’ve struggled through and learned a [Read more…] about Concepts in Linear Regression you need to know before learning Multilevel Models

Tagged With: centering, dummy coding, effect coding, interaction, interpreting regression coefficients, mixed model, multilevel model, Polynomial terms

Related Posts

  • How to Combine Complicated Models with Tricky Effects
  • When NOT to Center a Predictor Variable in Regression
  • Dummy Coding in SPSS GLM–More on Fixed Factors, Covariates, and Reference Groups
  • Specifying Fixed and Random Factors in Mixed Models

Primary Sidebar

This Month’s Statistically Speaking Live Training

  • Member Training: Moderated Mediation, Not Mediated Moderation

Upcoming Workshops

    No Events

Upcoming Free Webinars

TBA

Quick links

Our Programs Statistical Resources Blog/News About Contact Log in

Contact

Upcoming

Free Webinars Membership Trainings Workshops

Privacy Policy

Search

Copyright © 2008–2023 The Analysis Factor, LLC.
All rights reserved.

The Analysis Factor uses cookies to ensure that we give you the best experience of our website. If you continue we assume that you consent to receive cookies on all websites from The Analysis Factor.
Continue Privacy Policy
Privacy & Cookies Policy

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Non-necessary
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
SAVE & ACCEPT