I'd like to know how to calculate each player's chances of winning a tennis tournament, based on my estimations of their chances of winning each possible match.

Here's an example bracket, let's say I want to figure out Player A's chances of winning the tournament:

Round 1:

Player A vs. Player B (I think A has a 80% chance to win)
Player C vs. Player D (I think C has a 65% chance to win)
Player E vs. Player F (I think E has a 60% chance to win)
Player G vs. Player H (I think this match is a coinfilp)

Round 2 scenarios:

I think Player A would have a 75% chance of beating Player C, and a 60% chance of beating Player D.

Final Round scenarios:

I think Player A would have a 75% chance of beating players E and F, and a 60% chance of beating Players G and H.

Also, would it be possible to make a spreadsheet where I could have a template of a bracket, then I'd just need to fill in the all players and the probability of them winning each potential matchup? With the objective being to calculate each player's chances of winning the tournament, or advancing to a later round?

You're missing the probabilities of E or F vs. G or H.


Yes, such a thing is possible.

You did not give all the needed info. You need to give E vs G and E vs H and F vs G and F vs H to get the prob of A facing E, F, G, or H for the final.

Yes I think a spreadsheet can be developed. In this case there are only 8 possibilities:

A beats B and then wins vs C and then wins vs. E or F or G or H (4 ways) =0.8*0.65*0.75*[ Pr(E)*Pr(Beats E)+P(F)*Pr(Beats F) etc. ]

A beats B and then wins vs D and then wins vs E or F or G or H (4 ways)