Answer: You'll be sorry you asked. It's an attempt to apply Sabermetrics to Survivor. (Sorry yet? If not, read on.) Essentially, an attempt to answer: "Who's the best Survivor player?"
So you might notice that we have two ways of measuring total scores. One is the Survival Score (SurvSc). It's simply the sum of three components: Challenge Win% (ChW%), Tribal Council% (TC%), and Jury Vote% (JV%, irrelevant until the finale). So SurvSc = ChW% + TC% + JV%, for a max score of 2 (3 after the finale).
The other score is the Survival Average (SurvAv). It's a simple sum of fractional Challenge Wins (ChW), weighted TC Ratio (wTCR), and a weighted JuryVote% (to be exact, JV% times 6). Or SurvAv = ChW + wTCR + (6 * JV%). This has two advantages over SurvSc: (1) It's always a positive number (or zero), since tribal council votes are treated as a weighted ratio (instead of a potentially negative sum), and (2) it has a larger spread, and in looking at past seasons, we just feel it better represents the games we saw.
Neither ranking is perfect, however, and we're open to suggestions. Feel free to comment below with potential improvements. Check the individual leaderboard and overall season scores to see how they work.
From time to time, a player leaves even when the tribe hasn't actually spoken. Here are the adjustments made in scoring when that happens.