Have you visited the trials?

I was having a chat with analysts that just had a project dumped on their lap. They were questioning previous analyses as complex and were thinking of doing something much simpler and effective to make some progress on the project. There had been many delays due to personnel issues, so it was the time to move faster. They were chatting with me/asking my opinion because I was familiar with one of the data sets.

I was struggling with some of the assumptions they were making until I asked “Have you visited the trials? At least one of them…”. The answer was “no, we haven’t”.

It may sound like a silly question, as an analysis of an experiment is just applying a recipe, isn’t it? Nevertheless, this is not your typical textbook analysis, where everything is nice and square and tidy. These are forestry experiments, growing on the crappy end of land use classes, on hilly terrain, where different parts of the trial have different aspect, slope, fertility, drainage, etc… That’s why we care about the experimental design and anything else that helps us reduce environmental noise (x/y positions, spatial modelling of residuals, etc).

Becoming familiar with the site, the material being tested and the history of the experiments is not optional.