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Since 2019, offenses converting 4th-and-1 between their own 40 and the opponent’s 30 have succeeded 71.3 % of the time. A made kick from 52 yards returns 2.15 expected points; a conversion keeps a drive alive worth 2.57 expected points, a surplus of 0.42 before factoring in miss rate, which climbs to 28 % outdoors in December.
Green Bay’s staff built a live win-probability script that pings the sideline tablet with a binary flash-green for go, red for kick-updated with in-game roof angle, kicker fatigue index, and opposing red-zone defense DVOA. Over the last three seasons, their 18 % aggression rate above league average on 4th-and-short has translated into +22.4 point differential, roughly one extra victory per year.
Baltimore keeps a weather-corrected distance matrix: every mile-per-hour of wind above 13 mph devalues a kick by 0.07 EPA. When the gust hit 17 mph at Soldier Field in Week 6, the model nudged John Harbaugh to punt on 4th-and-4 from the 37; the ball was downed at the 5, and the ensuing drive produced a safety that swung win odds by 11 %.
The league’s 2026 tracking data show quarterback sneaks gaining 1.82 yards per attempt on 4th-and-1 when the offense operates with < 0 :15 on the play clock, versus 1.36 with earlier snaps. Philadelphia’s analysts spotted the edge and now stall until the clock hits :08 before every short-yardage snap, cutting their stuff rate from 16 % to 9 %.
Combine those micro-edges-go rates, wind decay, snap cadence-and the analytics desk estimates a conservative staff leaves 0.7 wins on the table each fall, the difference between home-field rest and a wild-card exit.
Mapping EPA to Field Position for 4th-and-1 on Your Own 35
Go. From the minus-35, 4th-and-1, the offense keeps the ball: +0.78 EPA. A punt from that spot returns +0.12 EPA after factoring in 42-yard net and fair-catch at the 23. Converting at 68 % league rate, you expect 2.57 points on the next drive; giving the ball away you spot the opponent 1.79 expected points. The 0.78 minus 0.12 gap equals 0.66 EPA every time you choose aggression.
Flip the coordinates and the story stays. Between the 40 and the 30, the break-even conversion rate needed for a positive EPA is 49 %. League-wide success on 4th-and-1 sits at 68 %, so even if your offense ranks 25th, the rate still clears 60 %. Only six franchises since 2018 have fallen short of 49 %, and all six fired their play-caller mid-season.
Field position shifts fast. Fail at the minus-35 and the opponent starts at plus-35, 1.79 EPA. A punt plus 42-yard net moves them to minus-23, 0.78 EPA. The delta is 1.01, smaller than the 1.25 EPA swing you gain by converting. In short, the downside of a miss is smaller than the upside of a first down. Track five years of drives and the cumulative delta reaches 187 points for teams that leaned toward staying on the field.
Build the call sheet: list four short-yardage concepts that stress the A-gap versus man and four that attack the edge versus zone. Script the first eight plays of the drive so the fourth-down snap arrives with tempo, no substitution. If the defense sends goal-line personnel, check to spread; if they stay base, check to heavy. The math is already done; the only variable left is whether you trust it.
Feeding Next Gen Stats Into a Custom Win-Probability Model in Real Time
Stream the live feed from Zebra’s 20-Hz tags straight into a Python worker on AWS Fargate; within 0.3 s, parse x, y, v, and acceleration vectors for all 22 players plus the ball. Append the most recent 120 frames to a rolling window, feed it through a 512-neuron LSTM that was retrained on 2019-2026 tracking plus rbsa nflscrapR results, and output an updated win-probability delta for every second-and-10, third-and-4, or fourth-and-anywhere between the 50-yard line and the opponent’s 30.
- Drop any frame with a confidence < 0.95; interpolation artifacts bias the LSTM by 2.4 % on go-line decisions.
- Cache pre-computed expected points added (EPA) surfaces in an in-memory Redis store; retrieval latency falls from 11 ms to 0.8 ms.
- Calibrate the model weekly with the newest 256 regular-season drives; the calibration cut-off is Sunday 23:59 ET, and the refresh reaches the booth tablet by Monday 06:00 ET.
- Weight current-season data 3× heavier than prior seasons; without this, the residual error on late-season games spikes from 1.7 % to 4.1 %.
Overlay pre-snap personnel: if the offense deploys 11-personnel against a 5-man box, the win-probability edge for going is +0.074. Swap to 12-personnel versus a 6-man box and the same edge collapses to +0.013; the algorithm triggers a red flag on the OC’s wristband and flashes the recommended punt unit.
Integrate weather API in parallel: a 25-mph sustained gust drops the conversion likelihood from 49 % to 38 %; the model subtracts 0.052 from the go-aggressive index and adds 0.9 yards to the projected hang-time distribution for the punter. Stadium-specific airflow vectors come from five on-site anemometers sampled at 1 Hz; discard any reading that deviates more than 2σ from the median of the last 60 s.
Push the final binary-go or kick-via a 240-byte encrypted payload over a private 5 GHz link to the Microsoft Surface on the bench; round-trip latency is 180 ms. Log every decision with a millisecond Unix timestamp, hash the payload with SHA-256, and archive to S3 Glacier for compliance; the league’s football ops audit team can reproduce any Week 7 choice in under 45 s.
Adjusting Model Output for Weather, Score, and Clock With a 15-Second Python Script
Multiply the baseline go-for-it probability by 0.87 when wind exceeds 20 mph; anything below that threshold keeps the 1.0 multiplier. Ten-year tracking from 256 outdoor December games shows conversion rate drops 6.3 percentage points once gusts hit 21-25 mph. Paste the one-liner prob *= (1 - 0.013 * ws if ws > 20 else 1) right after the model call and re-run.
Up 8 with 7:14 left? Subtract 0.11 from the push model’s break-even. Down 3 with 0:45 left? Add 0.18. The script keeps a tuple (sc, tm) for score and time; the delta applies in a single vectorized step.
| Score gap | 0-5 min | 5-10 min | 10+ min |
|---|---|---|---|
| Down 1-3 | +0.20 | +0.14 | +0.05 |
| Tied | +0.09 | +0.07 | +0.03 |
| Up 1-6 | −0.05 | −0.08 | −0.12 |
Precipitation knocks 0.04 off every active third-down conversion, so the fourth-down model inherits the same dampener. Engineers pulled 9,800 plays where radar tagged >0.1 mm h⁻¹; success rate slid from 48.2 % to 44.1 %. The code appends prob *= (0.96 if rain else 1) and exits.
Field temperature below 30 °F cuts kicker distance by 4.7 yards; the go model inflates the required yards-to-go by that amount before comparing to the kicker’s cold-weather range. A franchise that adopted the tweak in 2025 saved 11 expected points across five frigid home games.
Clock management overrides everything inside 1:20. If you have two timeouts and trail by 4-8, the script raises the go threshold to 85 % regardless of distance; burning a possession outweighs field position. The snippet is if tm < 80 and to >= 2 and -8 <= sc <= -4: prob = 0.85.
Barcelona’s analytics department borrowed the same logic for short-corner probability in soccer; a forward reached 94 goals, one shy of Ronaldinho’s Catalan tally-details here: https://chinesewhispers.club/articles/barcelona-forward-one-goal-from-matching-ronaldinho.html.
Total runtime on a 2019 MacBook Air: 0.14 s for 1,000 scenarios. Export the adjusted probabilities to the wristband printer and the staff gets a weather-score-clock aware chart before the chain crew resets.
Communicating Go-for-It Probability to the Headset Using a 0-100 Color Bar
Send the digit 87 flashing neon-green when the model spits out a 0.55 win-probability edge on 4th-and-2 from the +38; anything above 80 triggers the green band and the play-caller has 2.3 seconds to wave off the punt unit. Drop to 31 and the bar burns amber, telling the headset the expected points swing is only +0.17, beneath the franchise’s preset +0.30 green-light floor.
Red slices-0-20-lock the offense on the bench; the bar broadcasts 14 against a dime-blitz look on 4th-and-5, translating to a 38 % conversion rate versus a 42 % field-goal make from 53 yards, so the ST coordinator gets the nod without a word exchanged.
Each shade refreshes every 0.18 s via the sideline tablet: GPS tags sync with the league’s 0.1-yard positional feed, then the Kalman filter smooths ball spot noise to ±0.06 yd before the neural net re-scores. The bar’s hue saturates when the defense tips a five-man box; a 0.9-man surplus raises the recommendation by 11 points, shoving 74 into the green.
Quarterbacks hear the integer only: Eighty-two means the tight end’s matchup carries a 67 % success probability against a safety in man, worth 0.38 EPA; twenty-four kills the sneak and boots it. The headset mic filters crowd roar at -18 dB so the digit arrives clean even at 128 dB on third-tier stands.
Last season the club stuck to the bar on 127 of 134 fourth-down snaps, posted +52.4 EPA above baseline, and turned three bar-overrule punts into 19 lost points-enough to flip two one-score losses. The analytics intern now carries a backup pager vibrating in Morse: single pulse for green, double for red, triple if the tablet dies.
Countering Public Criticism With Post-Game PDFs Sent to Local Reporters
Attach a one-page file titled 4thDecision_WeekX.pdf within 90 minutes of the final whistle; include win-probability delta (+7.3%), expected points added (+1.8) and a 25-frame still sequence showing the split-second linebacker blitz that forced the quarterback to check to a slant. Send it to the eight beat writers who control 68 % of local print circulation; copy only the PR chief, never the owner, to avoid the optics of panic.
Frame every bullet as an answer to tomorrow’s radio talking points: Why not kick? earns a side-by-side graphic-field-goal success rate from the 38-yard line (74 %) versus conversion rate on 4th-and-3 versus man coverage (61 %)-followed by a 12-word quote from the special-teams coordinator noting the kicker’s 2-for-5 history from 50-plus in that direction. Add a QR code linking to the raw Next Gen tracking clip; reporters download the 4.7 MB file in 14 seconds and can embed the 15-yard route tree without re-encoding.
Keep the footer minimal: team logo, timestamp, URL to a dedicated GitHub repo containing the Python script that built the model, commit hash 9f3e2a1. After the 2025 season, franchises that adopted the ritual saw a 19 % drop in negative local headlines within 48 hours and a 0.4 % uptick in season-ticket renewal the following spring; the only outlier was a 34-31 overtime loss where the backup long-snapper sailed the ball, a variable no PDF could sanitize.