Mithrandir Metrics
NYM 2026-08-21 Refreshed Sep 2 06:00 AM ET
Section III · Betting · Player detail · 2026-08-21

Marcus Semien

NYM · Hitter · bats R · age 36
IN · 8 Negative regression Hitter-Friendly
MatchupNYM vs CWSSean Burke
Sample--career MLB AB
PROPS 3 available PERCENTILES 16 rows LINEUPS confirmed artifact NO PROSE templated rows only
Strikeouts · Palantir calibration review Last 14d ECE 0.053, 14d stable. This flags probability calibration, not a blanket model failure.
Strikeouts · Valinor calibration review Last 14d ECE 0.068, 14d stable. This flags probability calibration, not a blanket model failure.
Total Bases · Palantir calibration review Last 14d ECE 0.053, 14d error rising. This flags probability calibration, not a blanket model failure.
Tonight's props · all markets for this player
Home Run 0.5
P 11.4
F 11.7
V 14.4
Model 19.8% Market 13.2% Gap +6.1pp
FanDuel 630 tracking Open board
Total Bases 0.5
P 61.9
F -- in progress
V -- in progress
INSUFFICIENT LANES
Model 74.7% Market 75.6% Gap +13.7pp
BetMGM -310 tracking Open board
Hits 0.5
P 20.3
F -- in progress
V -- in progress
INSUFFICIENT LANES
Model 20.3% Market -- Gap +1.1pp
FanDuel 390 tracking Open board
RBI --
RBI · no production board

No production board publishes this player-market cell today.

Underlying skill · actual percentile with projection tick

Percentile strip

100th = best in MLB
Hitting · percentile strip
Barrel%5.3%
57
Exit velocity86.5
33
Hard-hit%36.3%
39
xBA0.322
53
xSLG0.517
55
xwOBA0.302
46
BB%7.6%
40
Bat speed66.4
14
K%21.9%
53
Defense · percentile strip
Arm Runs-0.2 · 2B
14
Arm Strength85.3 · 2B
35
Outs Above Avg-5.0 · 2B
6
Range Runs-4.5 · 2B
14
Baserunning · percentile strip
Base Running Runs-0.3 · 2B
36
SB Success Rate66.7% · 2B
20
Sprint Speed28.1 · 2B
69

Context

projection · regression · matchup
Projected range0.272 to 0.366
RegressionNegative · -0.001
Opposing pitcherSean Burke
EnvironmentHitter-Friendly
Lane calibration receipts
Lane Health 2026-09-02
Palantir 18081 props Brier 0.118 ECE 0.008 14d stable
Fangorn 18081 props Brier 0.118 ECE 0.009 14d stable
Valinor 12423 props Brier 0.112 ECE 0.004 14d stable
Palantir 1591 props Brier 0.247 ECE 0.006 14d stable
Fangorn 53 props Brier 0.257 ECE 0.119 sample building
Valinor 1087 props Brier 0.248 ECE 0.016 14d stable
Palantir 8613 props Brier 0.238 ECE 0.047 14d error rising
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir 683 props Brier 0.163 ECE 0.031 14d stable
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir 900 props Brier 0.256 ECE 0.059 14d error falling
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)
Palantir tracking in progress (0 logged)
Fangorn tracking in progress (0 logged)
Valinor tracking in progress (0 logged)