I am doing a simple Random Forest classification in Google Earth Engine. I try to classify upland, water and wetlands, using 25 variables derived from one year of Sentinel-1 images. The classifier works well and the accuracy is okay, but now I want to calculate a variable importance for my classifier.
There seems to be no function in Earth Engine for calculating variable importance. The only workaround I could think of is exporting the stacked image to R, and do the classification there. However, this might be a complicated solution, due to the size of the study area and the high number of variables. Is there a simple work-around to calculate variable importance in Earth Engine?
Best Answer
No easy easy way to compute variable importance (yet) but you could try computing your accuracy multiple times, withholding one column each time. The largest decrease in accuracy will correspond to withholding the most important variable. then repeat leaving that one in and withholding the other N-1 columns, 1 at a time. etc.