OptinMon 34 - Getting Started with R

Member Training: Plot Estimated Marginal Means in R

November 3rd, 2025 by

Estimated marginal means (EMMs)—sometimes called least-squares means—are a powerful way to interpret and visualize results from linear and mixed-effects models. Yet many researchers struggle to extract, understand, and plot them.

In this 60-minute hands-on tutorial, participants will learn how to compute, interpret, and visualize EMMs using only base R functions together with the emmeans, car, and lme4 packages. We will start with simple linear models and progress to mixed models with random effects, highlighting how to obtain EMMs, confidence intervals, pairwise contrasts, and publication-ready base R plots. The session emphasizes conceptual understanding and practical code you can adapt immediately to your own analyses.


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.

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About the Instructor

Manolo Romero Escobar is a seasoned statistical consultant and psychometrician with a passion for helping researchers.

Throughout his career, Manolo has worked extensively as a research and statistical consultant. He has served a diverse range of clients including health researchers, educational institutions, and government agencies. With a focus on linear mixed effects modeling, latent variable modeling, and scale development, Manolo brings a wealth of knowledge and experience to every project he undertakes.

Manolo is also proficient in statistical programming languages such as R, SPSS, and Mplus, and has experience with Python and SQL. He is passionate about leveraging technology as an educational and training tool, and he continuously enhances his skills to stay at the forefront of his field.

He holds a B.A. and Licentiate degree in Psychology from Universidad del Valle de Guatemala and a M.A. in Psychology (Area: Developmental and Cognitive Processes) from York University.

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, 130+ 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.


How to Pick an R Package

April 24th, 2023 by

One big advantage of R is its breadth. If anything has been done in statistics, there is an R package that will do it.

The problem is that sometimes there are four packages that will do it. This is big problem with R (and with Python for that matter). (more…)


Member Training: R for Menu Users Software Tutorial

December 30th, 2021 by

In this nearly 6-hour tutorial you will learn menu-based R libraries so you can use R without having to fuss with R code. These libraries don’t cover everything R can do, but they do quite a bit and can set you up to make running R much easier.

(more…)


Member Training: What’s the Best Statistical Package for You?

February 1st, 2019 by

Choosing statistical software is part of The Fundamentals of Statistical Skill and is necessary to learning a second software (something we recommend to anyone progressing from Stage 2 to Stage 3 and beyond).

You have many choices for software to analyze your data: R, SAS, SPSS, and Stata, among others. They are all quite good, but each has its own unique strengths and weaknesses.

(more…)


The Advantages of RStudio

September 26th, 2017 by

There are multiple ways to interface with R. Some common interfaces are the basic R GUI, R Commander (the package “Rcmdr” that you use on top of the basic R GUI), and RStudio.

When I first started to learn to use R, I was bound and determined to use the basic R GUI.

As someone who was already used to programming in SAS, I wasn’t looking for a (more…)


What Really Makes R So Hard to Learn?

September 19th, 2017 by

If you are like I was for a long time, you have avoided learning R.

You’ve probably heard that there’s a steep learning curve. Or noticed that the available documentation is not necessarily user-friendly.

Frankly, both things are true, to some extent.

R is Open-Source

The best and worst thing about R is that it is open-source. So there is no single (more…)