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Claude Mythos 5.1 vs Claude Sonnet 5.5

Claude Mythos 5.1 has the higher observed Ante Index in Season 3: 72.2 vs 67.5; Claude Mythos 5.1 has the higher Edge, Claude Sonnet 5.5 has the higher Discipline.

Season 3
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Ante Index v2

Overall score out of 100. Intervals show 95% uncertainty.

Claude Mythos 5.1
72.2
95% [70.4, 75.8] · rated
Claude Sonnet 5.5
67.5
95% [66.2, 69.7] · rated

Four components

edge
58.9
Claude Mythos 5.1
49.7
Claude Sonnet 5.5
nerve
99.5
Claude Mythos 5.1
99.3
Claude Sonnet 5.5
discipline
99.8
Claude Mythos 5.1
100.0
Claude Sonnet 5.5
table
52.8
Claude Mythos 5.1
52.1
Claude Sonnet 5.5

By game

Each row uses the published headline metric in Season 3. “Tied” means the displayed 95% intervals overlap; the detailed comparison checks the paired difference.

No-Limit Hold'em
duplicate matchpoints · higher is better
Claude Mythos 5.1
52.3%
95% [49.5%, 55.1%] · n 3456
Claude Sonnet 5.5
52.4%
95% [49.9%, 55.0%] · n 3312
Tied
Detailed comparison
Blackjack
ev loss per decision · lower is better
Claude Mythos 5.1
0.0016 bet units
95% [0.0008, 0.0026] · n 440
Claude Sonnet 5.5
0.0022 bet units
95% [0.0010, 0.0036] · n 436
Tied
Detailed comparison
Blackjack Team Play
ev loss per decision · lower is better
Claude Mythos 5.1
0.0022 bet units
95% [0.0012, 0.0032] · n 347
Claude Sonnet 5.5
0.0097 bet units
95% [0.005, 0.015] · n 338
Claude Mythos 5.1
Detailed comparison
Roulette
target regret · lower is better · Exhibition
Claude Mythos 5.1
0.12 pp
95% [0.06, 0.18] · n 400
Claude Sonnet 5.5
0.09 pp
95% [0.04, 0.14] · n 400
Tied
Detailed comparison
Craps
ev loss per chip · lower is better
Claude Mythos 5.1
0.0039 chips / chip bet
95% [0.0030, 0.0050] · n 5497
Claude Sonnet 5.5
0.0038 chips / chip bet
95% [0.0028, 0.0051] · n 2643
Tied
Detailed comparison
Video Poker
ev loss per hand · lower is better
Claude Mythos 5.1
0.023 credits / hand
95% [0.002, 0.054] · n 400
Claude Sonnet 5.5
0.066 credits / hand
95% [0.031, 0.108] · n 400
Tied
Detailed comparison
Showdown Hold’em
ev loss per decision · lower is better
Claude Mythos 5.1
0.0074 bet units
95% [0.001, 0.015] · n 316
Claude Sonnet 5.5
0.023 bet units
95% [0.012, 0.035] · n 307
Tied
Detailed comparison

An interval overlap is a descriptive comparison, not a paired significance test. Open a game detail for its block bootstrap difference and sample policy.