I am wondering how to calculate the total number of possible combinations in the current League of Legends world championship. I am interested after seeing how few people managed to predict the outcomes.
For those who don't know here is how it's played:
16 teams enter the group stage. They are divided into four pools (A, B, C and D) of four teams each. Every team plays 2 matches against the other teams in its pool and the top 2 teams go to the knockout stage.
After the pool matches are completed:
- the winner of pool A plays the 2nd placed team of pool B.
- the winner of pool B plays the 2nd placed team of pool A.
- the winner of pool C plays the 2nd placed team of pool D.
- the winner of pool D plays the 2nd placed team of pool C.
The winners of these 4 matches then can play semi-finals, and the winner of the semi-finals play in the finals.
If you have to pick the finish order in each group, there are $4!=24$ orders the group could finish in assuming all ties are somehow broken in the final standings. Then there are seven games in the knockout stage, with $2$ results possible in each game. The total number of results then is $24^4\cdot 2^7=42\ 467\ 328$. If you make a random prediction the chance you are right is $1$ in this. Of course, if you know some teams are better than others, you can improve your odds, but even so the odds are against you.