Conceptual and Statistical Knowledge

 

Tutorial/R code for creating plots for 2-way interactions

ggplot2, as I’ve already made clear, is one of my favourite packages for R. And since that original post about ggplot2 remains one of my most frequently visited, I thought I would proceed with starting a series of posts called “Make It Pretty”, all …

Tutorial/R code for creating scree/parallel analysis plots

With this post, I’m going to be showing how you can use the psych package in conjunction with ggplot2 in order to create a prettier scree plot with parallel analysis–a very useful visualization when conducting exploratory factor analysis.

Type I Error Rates are Not Usually Inflated

The inflation of Type I error rates is thought to be one of the causes of the replication crisis. Questionable research practices such as p-hacking are thought to inflate Type I error rates above their nominal level, leading to unexpectedly high …

Understanding Bayes: A Look at the Likelihood

A blog about bayesian statistics

Understanding Bayes: Visualization of the Bayes Factor

An abstract about Understanding Bayes and visualising Bayes Factor

Understanding psychology as a science: An introduction to scientific and statistical inference

How can we objectively define categories of truth in scientific thinking? How can we reliably measure the results of research? In this ground-breaking text, Dienes undertakes a comprehensive historical analysis of the dominant schools of thought, key …

Understanding Statistical Power and Significance Testing: an interactive visualization

Much has been said about significance testing – most of it negative. Methodologists constantly point out that researchers misinterpret p-values. Some say that it is at best a meaningless exercise and at worst an impediment to scientific discoveries. …

Unlikely Results

Why most published scientific research is probably false

Using R and lme/lmer to fit different two- and three- level longitudinal models

I often get asked how to fit different multilevel models (or individual growth models, hierarchical linear models or linear mixed-models, etc.) in R. In this guide I have compiled some of the more common and/or useful models (at least common in …

Visualizing a One-Way ANOVA using D3.js

A blog post and tutorial on visualizing one-way ANOVA