Round 3 tested one hypothesis from round 2's data: levels the agent rated 3
carried 59% more 反差 than the rest, so select for it. With both rounds now at
~100 runs, the answer is in and it is no. The back band went from 2.39 ± 0.10 to
2.19 ± 0.08, roughly two standard errors apart, and the levels averaging 2.5 or
better fell from 11 to 6. Contrast is real and it does correlate with being
rated harder; selecting on it does not produce harder levels.
The low retest reliability does not rescue the change either — r = 0.55 limits
ranking one level against another, not the mean of eighteen levels measured a
hundred times.
So round 2's levels are the ones handed over, rebuilt from its runs via
round-set --emitCampaign. select-50 cannot reproduce them: the pool it drew
from has been rebuilt since, so the same flags now return different levels. The
runs are the record.
Rule bot on the shipped set: 50/50 cleared, dead taps 0.00, blind rotations
0.12, worst blind streak 1. 198 tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The round comparison was about to be wrong. levels/campaign-50-r2.json was
copied from levels/campaign-50.json to preserve "the set round 2 played", but
select-50 writes that path in place and several selection experiments ran
between the round and the copy. The file kept 28 of the 50 boards round 2 had
actually played and 46 of round 3's — so the comparison was scoring one round
against another round's levels, and it read as round 3 regressing.
Runs store the whole board and its campaign index, so a round is its own record
and cannot drift. round-set.mjs rebuilds it, the report uses that, and the
snapshot file is gone rather than left lying around looking authoritative.
With the rounds correctly matched, round 3 is not a regression and not an
improvement: back band 2.17 against round 2's 2.39, on a rating that retests at
0.55, which is not enough to separate seventeen levels. The report says that
rather than picking whichever reading flatters the change.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
