All posts tagged statistics

Visualising the bootstrap with shiny

27 May 2017 shiny visualisation statistics teaching

You can try out bootstrapping with my new shiny app.

Bootstrapping is a really useful statistical tool. It relies on re-sampling, with replacement, from a sample of data you have acquired. The idea is that by re-sampling your sample over and over again, you simulate running studies over and over again. It’s obviously not exactly analogous - sampling bias in...

Univariate k-means clustering

27 Jan 2017 statistics data kmeans clustering

Finding structure in your data

Often data is distributed normally. But sometimes, there is sub-grouping in your data that is worth exploring a bit more: For example, a subset of your data is drawn from a different population, and therefore has a different mean. One popular technique to find these clusters without any prior knowledge...

Visualising Confidence Intervals

19 Nov 2016 visualisation statistics teaching

Clearing up a misconception with confidence intervals

Confidence intervals are a nice way to present your results. They get you away from the dichotomous nature of p-values, and allow you to express the precision of the variable of interest. Whether it is the difference between two groups in a t-test or the slope of a linear regression,...

Visualising a 2x2 ANOVA

16 Nov 2016 visualisation statistics teaching

One way to make clear what is being calculated in a two-way ANOVA

The factorial design ANOVA (or Analysis of Variance) is maybe one of simplest yet most used tools in psychological research. It’s a test of mean differences between groups, but it tests for those mean differences using a “Variance explained” approach. If we assign incoming participants to one of 2 levels...