I have prepared a grid-based simulation model with 20 grid points. To validate my model, I took two sets of measurement on the floor and 0.87m height. I compared the average illuminance acquired from measurement and simulation. On the floor, I can see an error rate of 10% and for 0.87 m height, 1%. For the measurement, I have used a clear sky condition on the 23rd of November 14:30 to 16:00. My question, what is the maximum allowable error range for such kind of comparison? can anyone comment from own experience? or guide me to the related document?
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