S J Welham: Statistical Consultancy

I am an applied statistician with over 30 years experience of successful consulting with scientists in agricultural, biological and ecological research. I have particular expertise in the design, analysis and interpretation of field and laboratory trials.

I am the leading author of ‘Statistical Methods in Biology’ by Welham, Gezan, Clark & Mead (CRC Press, 2014), a textbook to introduce scientists to the design and analysis of simple experiments, which arose out of many years of training researchers in these topics. See the book website (including data and example programs) here: www.stats4biol.info.

I now work independently, please contact me (here) if you would like to discuss potential projects.



I started my career at Rothamsted Research (then Rothamsted Experimental Station) in 1987 working as a statistical consultant with researchers and on implementation of a REML algorithm within the Genstat statistical package.

In 2000, I moved to the London School of Hygiene and Tropical Medicine to study for a PhD on ‘Smoothing Spline Methods in the Mixed Model Framework’ (awarded December 2005).

In late 2003 I returned to Rothamsted and continued to work as a statistical consultant with researchers, in particular developing expertise in analysing genetic data and QTL. During this time l led the evolution of several statistical training courses for scientists, which turned into the book ‘Statistical Methods in Biology’, published in 2014.

From 2012-2016 I worked for VSN International, developing software for the analysis of linear mixed models. In June 2016 I left VSN to pursue a more varied career.

I have over 50 papers published in scientific journals, most as a statistical collaborator with scientists, some as development of statistical methodology. I am knowledgeable in most aspects of design, analysis, interpretation and reporting of field and laboratory trials in agriculture and plant biology. I am expert in REML analysis of unbalanced data sets, spatial designs and repeated measurements. Nowadays I mainly work with the statistical packages Genstat and R.