PropSims model, explained: how these pages are written

The byline "PropSims model, explained" means the page was written automatically by our software from the PropSims model's own output. Here is exactly what that involves.

What the software does

• Numbers come only from our data. Every projection, probability, price and result on these pages is read from the same files that power the rest of the site: the 10,000-simulation projections, the props board, the append-only forecast log, and final box scores.
• Fixed templates, no invented facts. Sentences come from a set of hand-written templates. The software picks a wording variant per item so pages don't all read the same, but it never adds a number, quote, or piece of news that isn't in the data. No language model writes or edits facts.
• News is only what our feeds show. Status changes come from the ESPN and nflverse injury feeds our live updater reads about every 7 minutes during game windows and about every 2 hours (8 a.m. to 8 p.m. CT) on other days. We do not report rumors or quotes. Each item shows the model's before-and-after numbers from that refresh.
• Noise is filtered. Re-running a game's simulations moves every projection slightly. On each news item we measure that noise on teams with no status change and only list moves larger than it.
• No page without substance. A news change that moves nothing beyond noise gets a one-line entry in the feed, not its own page. Weekly articles are only generated while at least four of the week's games are still to be played. A recap is only written if we published projections before kickoff and the final box score matches enough players.
• Updates are stamped. Weekly articles regenerate when the model's numbers change (for example after injury news) and show a "last updated" time; once the week's games are underway the last pre-game version is kept as it was.

Betting content rules

• Sides are labelled by what our validation shows: unders passed our out-of-sample backtest of the pick rule; overs did not, so every over is labelled unproven. A backtest is not a live record.
• How picks are graded (official record). Official record: only each pick's final pre-kickoff version counts (the latest row we logged for that player, stat, side and book before kickoff), and only when that version was priced with our market-blended fair probability, which is what the props board showed. Rows whose final version was still priced on raw simulation probability (the first board of Oct 4, 2026, logged 7:09 a.m. CT, before the site switched to fair probabilities at 8:22 a.m. CT) are graded and shown, but kept out of the official record. A player with no box-score line who appears in the play-by-play is graded as 0 in every stat; one who does not appear is void. Rows outside the official record are never deleted or hidden: recaps and the Track Record list them, marked "No (raw sim)", with their results. The log itself is append-only; grading is recomputed from it, never edited.
• Results are reported in full, losses included, at the posted prices. We make no win-rate claims beyond the graded record on the Track Record page.
• No "locks", no guarantees. 21+ only. Gambling problem? Call 1-800-GAMBLER (1-800-426-2537).

Known limits

• Recaps compute FanDuel points from the ESPN box score without 2-point conversions. A player with no box-score line is shown as such; for grading, he counts as 0 in every stat if he appears in the play-by-play (he played but recorded nothing), otherwise his props are void.
• The model's general strengths and weaknesses are on the main methodology page.

Questions or a correction? The data behind every page is public on this site. For entertainment and informational purposes only. 21+.