[dnackoul]

>There needs to be parity within the matchups and across the season.

I'm not sure how widely known this is, but the actual matchups, not order and dates, are completely deterministic.

Teams play their division twice for six games. They play the other three teams in their conference with the same division standing last season (e.g. division champs will play each other). They play four teams from a rotating division in the other conference. And finally they play the remaining three teams from a rotating division in their conference.

I've always been a football fan but it took me a while to realize the NFL doesn't actually schedule rivalries like Brady/Manning every year, they just happen because those teams consistently win their division.

[s73ver]

The matchups are deterministic. When they happen, however, is not. When making the schedules, they need to take into account rivalries (you probably don't want to have Cowboys/Redskins, Packers/Vikings, and Steelers/Bengals all happening on the same weekend), traveling, and potential playoff contenders. A game between two teams fighting for a playoff spot or division title is much more exciting in December than it is in October.

[sjs382]

Also, for teams in the opposite conference, 2 are home and two are away. So, every team plays each team in the opposite conference every four years, but only plays them each at home every 8 years.

[ghaff]

I didn't realize that.

The workflow would be interesting. Presumably you have some hard and fast rules and then you try to encode bad/good/better rules. Let the computers churn out options. Maybe iterate with some new rules. The start going through the options manually.

I've worked on conference schedules :-) We don't use computers but it usually goes something like heuristics -> coarse optimization -> hand-tuning.