Posts

Learning Python as an R user

Last updated on April 1, 2020 1 min read tutorial

Presidential primary candidate name recognition matters

Key takeaway FiveThirtyEight claims that early national primary polls can become more useful for predicting party nomination success if …
Last updated on July 31, 2019 12 min read opinion, U.S. politics

Testing Conditional Indirect Effects/Mediation in R

This post builds on a previous post on Testing Indirect Effects/Mediation in R. What is mediation? There are many ways to define …
Last updated on February 24, 2019 16 min read indirect effect, general linear model, mediation, regression, tutorial, demonstration, moderation, interactions

Using Principal Components or Common Factor Analysis in Social Psychology

Multidimensional Scaling, the precursor to Principal Components Analysis, Common Factor Analysis, and related techniques …
Last updated on February 25, 2019 24 min read common factor analysis, tutorial, principal components analysis, multidimensional scaling, R, measurement, demonstration, reliability

Introduction

The image above depicts a sailing ship entering unchartered waters, which I can only guess is a metaphor for the vast natural world …
Last updated on February 14, 2019 2 min read philosophy of science

Learn R for Psychology Research: A Crash Course

Introduction I wrote this for psychologists who want to learn how to use R in their research right now. What does a psychologist need …
Last updated on February 16, 2019 23 min read tutorial, demonstration, R

Plotting Adjusted Associations in R

What is a correlation? A correlation quantifies the linear association between two variables. From one perspective, a correlation has …
Last updated on February 14, 2019 10 min read demonstration, general linear model, plotting, R, regression, tutorial, covariates

Probing and Plotting Interactions in R

What is moderation? Moderation refers to how some variable modifies the direction or the strength of the association between two …
Last updated on February 16, 2019 14 min read regression, plotting, interactions

Testing Between-Subjects Contrasts in R

Between-Subjects Factors A between-subjects factor refers to independent groups that vary along some dimension. Put another way, a …
Last updated on February 14, 2019 10 min read ANOVA, contrasts, general linear model, between-subjects designs

Testing indirect effects/mediation in R

What is mediation? There are many ways to define mediation and mediators. Here’s one way: Mediation is the process by which one …
Last updated on February 24, 2019 8 min read mediation, indirect effect, general linear model, tutorial, demonstration