When evaluating which model of the dataset to choose you'll want to know which version is the most accurate for your location. There are overall global statistics to consider or you can look at those results specific to your region of interest. Our validation results are always calculated using independent ground stations that have been quality controlled and have the best global coverage available.

Many people look at the Mean Bias Error to understand how closely the satellite data is matching ground observations in the same region or project area. It is a good way to get a quick idea of whether the satellite models may be over or under estimating actual available resource for a particular area.

When we discuss the accuracy of a particular dataset most people are referring to the "uncertainty" or the Standard Deviation of the bias seen over several stations in a particular region. The smaller the uncertainty the more likely that model is representative of conditions in that particular region and is not biased in a particular direction.

As part of our processing, we regularly update our global validation studies. The version that corresponds to the data currently available in the Solar Time Series Tools is available here.