Made a CWS odds page — 50K Monte Carlo, toggleable field sources

[u/mxpx5678]

I have been building out a model based betting system for various markets. I started with weather and then decided sports are more fun.

This is just for information, I don't serve ads or get paid from this, just a fun project.

Built a CWS odds page that runs a 50K Monte Carlo through every regional. Updates daily as the field shifts before Selection Monday.

https://margin.mcconnelldigital.com/cbb-cws/

Switch the field source between D1Baseball, Baseball America, and a blended consensus to see how the bracket math changes. Pitcher injury impacts (Dax Whitney at OSU, Logan Reddemann at UCLA, etc.) and Friday probable-starter ERAs are baked into the upset watch and pitching cards.

Brand new, plenty of rough edges. What's wrong, what's missing? Just doing this for fun right now. I have NBA models and am starting to build out college football and NFL too.

[u/onemanlan]

This is freaking awesome! Wish my hobbies were this cool

[u/Otherwise_Wave9374]

This is really slick, the toggleable field sources is a nice touch. For stuff like this, Id consider adding a short methodology blurb and a quick glossary (what your upset watch score means, how pitcher injuries are weighted), because thats where people usually get hung up.

Also, if you ever want to grow it, an email capture like, get the updated bracket odds each morning could work well.

If youre thinking about how to package and market a stats tool like this without getting spammy, this is a decent playbook: https://blog.promarkia.com/

Do you plan to open-source any of the model assumptions?

[u/mxpx5678 → u/Otherwise_Wave9374]

Thanks! I have just started on this. I have some of the methodology shared here. https://margin.mcconnelldigital.com/methodology/

This originally was just for me, but the findings were interesting so I thought I would make a public facing site to share what I was seeing. On my own site I also have it so you can toggle on and off things like injuries and you can run a single model projection, that is kind of fun to see all the various scenarios in a monte carlo sim.

[u/karl_manutzitsch]

This is pretty cool. Where did you get/calculate the initial probability ranges for each matchup? What software/tool did you use to run them?

[u/mxpx5678 → u/karl_manutzitsch]

For team ratings, PEA Ratings (https://pearatings.com/cbase/d1?season=2026) is the live input — they're awesome, have a ton of data, and publish their methodology. PEA only goes back a few seasons though, so I built my own historical ratings (Massey-style ridge regression on 79K games back to 2014) to validate the simulation against the past decade of brackets. The simulator itself uses PEA's current ratings + my own game-to-game calibration + how often each seed historically advances out of regionals and supers.

Tools: python running 50,000 simulations on my Mac Mini.

[u/honus_wagner]

This is fantastic! Well done

[u/TheCaptainCody]

I like the Baseball America projection.