User blog comment:Sirebel/Mathematician Required - Apply Within/@comment-27170954-20170727005221

i've given up...i still believe the true value of an upgrade can be estimated using statistical regression, but i haven't had the time time to dedicate. the real issue is collecitng enough independent data points.

I made a second pass at a set of upgrades and estimated the upgrade vales - the results were similar to what i posted before, with a few estimates deviating from actual values by 0.1.