David Alexander Lillis is an experienced researcher and statistician, having worked in research evaluation, agricultural and forestry statistics, and education research and statistics. Currently, David delivers lectures in mathematics, statistics, and research methods at the New Zealand Institute of Sport in New Zealand. He is the owner and Director of Sigma Statistics and Research Limited, a New Zealand-based consultancy specializing in training, software development, data analysis, and statistical modelling using R. David holds an Honor's degree and Master's degree in Physics and Mathematics, and a PhD from Curtin University in Perth, Australia.