Sunday Bulldog

About

Sunday Bulldog is Big Chicken's rule pointed at the NFL. It reads the home team's Kalshi ask, buys the home side when it is favoured but not heavily, and moves to the margin ladder when the win contract gets too expensive to be worth the risk.

The question is not whether home teams win. They do. The question is whether the market has already charged for that, and whether it charges the same amount in a league where every game is nationally priced and heavily traded.

Its own record matters less than the comparison. Run the same rule in the NFL, the WNBA and the NHL and the gap between the three is the finding, because the rule is held fixed and only the league changes.

The rule

Read the home team's Kalshi ask. At 50¢ or below, no pick. Between 50¢ and 80¢, buy the home team to win. Above 80¢, switch to the margin ladder and buy the rung priced closest to 70¢, only if it sits between 60¢ and 80¢ with 100+ contracts resting at that ask. Both the win leg and any margin rung have to clear the same gate first: 100 or more contracts resting at the ask, a contract that has traded at least once, and a bid-ask spread of 3¢ or tighter.

How it works

• Runs twice an hour inside a 48 hour window before kickoff, and stops 30 minutes out.
• Reads the home side's ask off the win market. At 50 cents or below there is no pick; between 50 and 80 it buys the home team to win at the ask, 100 contracts, held to settlement.
• Above 80 cents it switches to the home team's margin rungs and buys the one nearest 70 cents, only from rungs priced between 60 and 80 with 100 or more contracts resting at that ask.
• The house gate applies on both code paths: the win leg and the margin rungs each need 100 contracts resting at the ask, some lifetime trading and a spread of 3 cents or tighter before the price band is even consulted.
• One pick per game, ever. Re-running the job changes nothing, so the commit that first added the row is the timestamp that matters.
• The bid and ask it saw, the resting size, the declined win price on a ladder pick and the rule text it ran under are all written onto the row before kickoff.

It will not buy an NFL home side above 80 cents, and it will not widen the 60 to 80 cent rung band to manufacture a pick, so a week of heavy or awkwardly priced favourites can produce nothing at all.

What would prove it wrong

If home sides bought between 50 and 80 cents settle about as often as those prices implied, and the ladder rungs do no better than the win contracts they stood in for, there is nothing here that the market did not already know.

Why this rule

The same hypothesis as Big Chicken in a different league. If home chalk prices differently in the NFL than the WNBA, the difference is the finding.