First off, the basics: Our scores are not necessarily a means to measure performance within a season (even though we often treat them as such). Instead, they're an attempt to quantify a Survivor contestant's likelihood of future success, much as predictive stats like WAR do in baseball. Essentially they assess: How likely is this contestant to win the next time they play Survivor? (Assuming no drop-off in performance over time). The theory is as follows:
The ideal Survivor contestant should have all three "tools" required to play: (1) challenge ability (easiest to quantify, just by counting wins), (2) social ability, and (3) strategic ability. The last two are difficult to measure, but both are reflected in a couple of measurable ways: tribal council performance, and receiving jury votes. Tribal council performance: A good strategic player will guide the vote in such a way as to (almost) always know, and vote for, the person that gets booted. Similarly, part of a good social game is being sufficiently in the loop to do the same thing. Conversely, a good social player should rarely receive votes against him- or herself (and it makes no strategic sense to receive lots of votes against, either). Getting voted out is not good strategy. Jury votes: The ultimate test of both strategic and social prowess is, of course, being able to convince the jury to award you the million dollar prize. So jury votes are, despite the small sample size, fairly important.
To put all this together, we created the Survival Average (SurvAv).
It's a simple sum of fractional Challenge Wins (ChW), weighted TC Ratio (wTCR), and (eventually) a weighted Jury%. This has two advantages over SurvSc, measured below: (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. As such, we've ordered the contestants based on this number in the table of complete Season 21 totals.
Our other metric, which we less favor, is the Survival Score (SurvSc). It's simply the sum of three components, expressed as percentages: Challenge Win% (ChW%), Tribal Council% (TC%), and Jury Vote%. So Survival score = ChW% + TC% + JV%, for a max score of 2 (3 after the finale).
Neither ranking is perfect, however, and we're open to suggestions. Feel free to comment below with potential improvements. We're keeping both scoring systems active through this season to see how they shake out.
- Challenge
stats
- ChW: Challenge Wins. For tribal challenges, a contestant earns a fraction of 1 win, depending on if they participated (no points for sitting out). So in a five-person tribe's win, each participant gets (1/5) of a point, or 0.2 points. Duels (or individual RCs as in Ep1) at Redemption Island count as half a challenge (and half a win). Individual challenge wins count as a full point.
- ChA: Challenge Appearances. Used to calculate ChW%. Fractional for tribal challenges (same as ChW), except sit-outs get charged for an appearance, because they could have participated.
- ChW%: Challenge Win%. Simply, ChW% = ChW / ChA.
- SO: The number of times a contestant sat out of a challenge.
- Tribal
Council stats
- VFB: Votes For Bootee. The number of times the contestant has voted for the person who was ultimately voted out. Applies only to initial votes (no points for revotes in case of a tie). Special case: In a final three TC, where only one vote is cast (by the F3 IC winner), only that vote counts.
- VAP: Votes Against the Player. The total number of tribal council votes cast against the contestant. Again, only initial votes count (no penalty for revotes), and here a hidden immunity idol (if played) erases the votes. In the special case of a final three tribal council above, only the F3 bootee receives a vote against.
- TotV: Total votes cast during the tribal councils the player has attended (again, only initial votes count). Used to adjust for different vote totals as tribes shrink.
- TCA: Tribal council appearances. The number of times a contestant has attended tribal council (at which they voted).
- TC%: Tribal Council percent. Attempts to reward voting for the bootee (which players controlling the vote almost always do), while punishing receiving votes yourself. The formula is: TC% = [VFB - (VAP/TotV)] / TCA.
- wTCR: weighted Tribal Council Ratio. Very similar in intent to TC%, but calculated as a ratio of VFB to VAP, while also scaling to a uniform number of TC appearances. The formula is as follows: wTCR =2* [VFB / (4+VAP)] x (14/TCA). I originally tried (1+VAP) to avoid dividing by zero, but this overly rewarded getting zero votes against relative to just one vote against, which seemed silly. (4+VAP) scaled that effect back comfortably. 14 was used as the scaling factor for TC appearances because there are usually 14 episodes, then a final scaling factor of 2 to bring maximal scores up to roughly even with ChW and JV% high scores.
- Jury
stats
- JVF: Number of jury votes for the contestant to win. Maximum nine (Earl Cole, Fiji), theoretically.
- TotJ: Total number of jurors. Necessary to not punish unanimous 7-juror winners (JT Thomas, Tocantins).
- JV%: The percent of total jury votes cast for the contestant, or Jur% = JVF/ TotJ. This number is used, raw, in SurvSc, and is scaled in SurvAv (multiplied by six) to make it similar in size to ChW and wTCR.
- Overall
scores
- Survival Score (SurvSc). It's simply the sum of Challenge Win% (ChW%) + Tribal Council% (TC%) + Jury Vote%, for a maximum possible score of 2 (3 after the finale).
- Survival Average (SurvAv). It's a simple sum of fractional Challenge Wins (ChW), weighted TC Ratio (wTCR), and (eventually) a weighted Jury%. The latter two max out at six points total, for a theoretical maximum score of around 18 or so.