free range statistics

I write about applications of data and analytical techniques like statistical modelling and simulation to real-world situations. I show how to access and use data, and provide examples of analytical products and the code that produced them.

Recent posts


Finding a circle in a chart

23 September 2023

I have a go at an 'insanely hard' (actually not that hard) problem to find the radius of a circle from someone's recruitment exercise


Model life tables

06 August 2023

I make an animation and a basic Shiny app to explore the United Nations' model life tables used for demographic estimates in countries where direct estimation of mortality rates by age isn't possible.


Log transforms, geometric means and estimating population totals

30 July 2023

A model that is 'improved' (in terms of making standard assumptions more plausible) by using a logarithm transform of the response will not necessarily be improved for estimating population totals.


Weighted versus unweighted percentiles

24 June 2023

When working with complex survey data where the weights are related to a continuous variable of interest, using a weighted rather than unweighted percentile rank will lead to different results towards the middle of the distribution; but the two measures will be highly correlated with eachother. Also, R reportedly calculates weighted percentile ranks much much faster than Stata.


Simpler drawing of Pacific choropleth maps

17 June 2023

I demonstrate the function I use to make it simpler to draw choropleth maps based on Pacific Island countries' and territories' exclusive economic zones.


Simulating confounders, colliders and mediators

04 June 2023

I do some simulations to reproduce a great figure by Wysocki et al; and show different data where the causal relationship between x and y is in the presence of a third variable that is either a confounder, collider or mediator.


Covid-19 vaccination rates in the Pacific

28 May 2023

I compare vaccination rates in the Pacific to GDP per capita and find the evidence isn't strong enough to say that there is a relationship between the two.


Showing women proportion of Parliamentarians on a map

26 May 2023

I have a go at showing the proportion of members of Parliament that are women on a map of the world, as an experiment in a tricky data visualisation


Transformations for compositional data

25 February 2023

I look into the use of Isometric Centralised Box-Cox Transformed Ratio for analysing compositional data like proportions of soil, time use or chemicals.


Pacific island choropleth map

13 October 2022

Drawing an annotated choropleth map of Pacific Island countries and territories.