## Why I use Panel/Multilevel Methods

I don’t understand why any researcher would choose not to use panel/multilevel methods on panel/hierarchical data. Let’s take the following linear regression as an example: , where is a random...continue reading.

I don’t understand why any researcher would choose not to use panel/multilevel methods on panel/hierarchical data. Let’s take the following linear regression as an example: , where is a random...continue reading.

The reason why football is so exciting is uncertainty. The outcome of any match or league is unknown, and you get to watch the action unfold without knowing what’s going...continue reading.

My first CRAN package, ggExtra, contains several functions to enhance ggplot2, with the most important one being ggExtra::ggMarginal() – a function that finally allows easily adding marginal density plots or...continue reading.

Histograms and bar charts are almost always a part of data analysis presentation. If it is made with R ggplot package functions geom_histogram() or geom_bar() then bar chart may look like...continue reading.

When building visualizations with ggplot2 in R I decided to create specialized functions that encapsulate plotting logic for some of my creations. In this case instead of commonly used aes function...continue reading.

A common way of illustrating the idea behind statistical power in null hypothesis significance testing, is by plotting the sampling distributions of the null hypothesis (\( H_0 $) and the...continue reading.

In this post I will show some different examples of how to work with map projections and how to plot the maps using ggplot. Many maps that are shown using...continue reading.

In this post I show some R-examples on how to perform power analyses for mixed-design ANOVAs. The first example is analytical — adapted from formulas used in G*Power (Faul et...continue reading.

Introduction Belia, Fidler, Williams, and Cumming (2005) found that researchers in psychology, behavior neuroscience and medicine are really bad at interpreting when error bars signify that two means are significantly...continue reading.

Today’s announcement at CERN of the latest research on the Higgs boson was truly extraordinary. Not only was the scientific achievement remarkable, but medias reporting of 5-sigma as a measure...continue reading.

Introduction I’ve been incredibly busy the last month, amongst other things I’ve moved about 400 miles from Umeå, in the north of sweden, to Stockholm. However, I’ve been working a...continue reading.

Introduction I had this idea that it’d be fun to look at all PubMed’s articles from 2011 and extract country affiliation for each individual country. So I set out to...continue reading.

Introduction My first PubMed script (An R Script to Automatically download PubMed Citation Counts By Year of Publication) extracted yearly counts for any number of search strings, by using PubMed’s...continue reading.

Introduction Continuing from what I wrote in my article An R Script to Automatically download PubMed Citation Counts By Year of Publication, I’ve now looked at article counts for journals....continue reading.

Update: I have created an interactive effect size visualization here Many times you read in a study that “x and y were significantly different, p < .05”, which is another...continue reading.

Background I believe there’s some information to be gained from looking at publication trends over time. But it’s really troublesome to do it by hand; fortunately it’s not so troublesome...continue reading.

Clinical Psychologists Theoretical Orientations 1960–2010 A recent study by Norcross & Karpiak (2012) looked at survey data from members of APA Division 12 (Society of Clinical Psychology). In their study...continue reading.

How do you easily get beautiful calendar heatmaps of time series in ggplot2? E.g:From MarginTaleI was impressed by the lattice-based implementation from Paul Bleicher of Humedica, which you can find...continue reading.

Introduction Google Ngram is a corpus of n-grams compiled from data from Google Books. Here I’m going to show how to analyze individual word counts from Google 1-grams in R...continue reading.

A Facebook group for psychologists in Sweden created a document where each member could type in were they live and what they work with. At the moment 192 psychologists have...continue reading.