I have been using the Maximum Likelihood Tool (Spatial Analyst extension, ArcMap 10.3.1) to classify a number of rasters into "Vegetation" and "Bare Ground" classes. I'd like to have some sort of quantitative measure for how reliable each of my classifications are (to report along with my data), so I've been generating a Confidence Raster for each image.
I understand that the Confidence Raster assigns each pixel an integer value (1-14, highest-to-lowest) that corresponds with the certainty of that pixel's class assignment. But do these integer certainties correspond to a specific probability/percentage?
In the example image discussed in the Desktop Help documentation, it says that "Value 1 has a 100 percent chance of being correct," "Value 5 has a 95 percent chance of being correct," but pixels with Value 14 "have a 0.005 percent chance of being correct." This scale doesn't make sense to me, so I doubt that each Level indicates a discrete 1% drop in likelihood. Also, I haven't seen these statements supported in any other journals or forums I've found online, so I'm hesitant to assume that's the end of it.