I want to make a custom ticket to ride map. I am trying to figure out what the mathematical formulas are behind the design. why alan moon decided which city pairs to put on the cards, and how to value each city pair.
The point value of tickets, as far as I can tell, in the minimum number of trains needed to link the two cities.
I wont explain all of them as you can check your self but here are a few examples to show what I mean.
Denver to El Paso ticket is 4 points. The shortest route is Denver to Santa Fe (2) to El Paso (2) totaling 4.
Boston to Miami ticket is 12 Points. The shortest route is Boston to New York (2) to Washington (2) to Raleigh (2) to Charlston (2) to Miami (4) which totals 12.
Seatle to New York is 22 points. The shorted route is Seatle to Helena (6) to Dululth (6) to Toronto (6) to Pittsburgh (2) to New York (2) totaling 22.
This works as far as I can tell for all other tickets and in my experience all other TTR games. There may be a few exceptions but if designing your own map then this seems to be the standard formula.
I'm not sure there's much math in that.
It's probably more lots and lots of playtesting.
When the 1910 expansion was released, the classic version provided tickets that balanced the game in a different (in most people's opinion: better) way because more games had been played, and more pros/cons of the standard ticket set had been discovered.