A Nerdy, Boring Statistical Analysis of Reach Advantage, Age and Win Probability (Part II)

latoya johnson

Double Black Card
@Green
Joined
Mar 27, 2016
Messages
1,416
Reaction score
324
@IngaVovchanchyn
A few days ago, I created this thread to analyze a fighter's win probability as a function of his age advantage over his opponent.

In general, I created this probability function:
upload_2017-6-5_23-18-52.png

Viewers observed that the inclusion of other input variables besides age would make the model more accurate.
Specifically, @MMAart asked for me to construct a model based on reach advantage too.

Ever wish you could determine probability based on multiple variables with one model?
upload_2017-6-5_23-26-12.jpeg

1. The Multi-Variable Probability Function
Now generalized to allow for the input of several variables:
upload_2017-6-5_23-41-36.png
Again note the absolute value operator for A indicating that this model only calculates the probability of the more likely outcome.




2. Is Reach an Advantage?
Analyzing the data, I made a startling discovery.
Having a reach advantage over your opponent is statistically irrelevant.
This is because having a reach advantage, in and of itself, indicates only that you're taller and therefore skinnier (height indicates skinniness due to weight restrictions) than your opponent. Being taller and skinnier is not an advantage.

However, having disproportionately long arms for your height is an advantage.
So the real advantage is reach/height.
This explains why fighters like Anderson Silva, Jon Jones, Conor McGregor, and Michael Venom Page are so dominant, where fighters like Stefan Struve, Alexander Gustafsson, and Charles Oliveira are eminently hittable.

Reach/height then became my second input variable.
Note that reach and height by themselves are statistically irrelevant (their sensitivity constants were both estimated to be zero!).




3. Calibrating the Parameters
After analyzing historical bout data and mathing around, I calculated these parameters.
upload_2017-6-6_0-13-40.png

See my original thread for details concerning the definition of the age advantage and the derivation of sensitivity constants, represented by k.



4. Win Probability Based on Age Advantage and Reach/Height
Here's the probability function applied to fighter win probability for the two input variables.
upload_2017-6-6_0-19-54.png

Note that Big K, the sensitivity constant of the net advantage, was estimated to be about .8937.




5. Daniel Cormier vs. Jon Jones (example)

Daniel's weighted age advantage is
upload_2017-6-6_0-37-45.png
Note that the prime fighting age is 27.99 years old.

Daniel's weighted reach/height advantage is
upload_2017-6-6_0-39-2.png

Daniel's weighted net advantage is
upload_2017-6-6_0-54-12.png

Since this is negative, we now switch to the favorite's perspective.
Jon's chance of victory is
upload_2017-6-6_0-51-22.png




Conclusion and Key Take-Aways
1. Neither reach nor height are advantages in fighting. However, having disproportionately long arms for your height (reach/height) is an advantage!

2. The average win probability of a fighter with a reach/height advantage was only 53%, indicating that it is still a weak determinant of bout outcomes
However, the average win probability of a fighter with an age advantage was 70%! So age is a very strong determinant of bout outcomes.

3. After expanding my sample size, I determined that the prime fighting age is actually 27.9921875 years old.
Hat tip to @fermaPY .

4. This model can be improved by expanding the sample size and inputting more variables. So far I've only entered two, age and reach/height.
 
Last edited:
Several posters @DIABOLUS have wondered how this model could be applied toward gambling.
I researched its effectiveness at gambling and came up with some interesting results.
I may post a gambling commentary if anyone's interested.


Also, for those of you wondering if you could do this too, you can. It's uber easy.
I have ALL the information and algorithms stored in an Excel file which I unfortunately cannot upload here for your convenience.
Here's a screenshot.

UFC 214 Odds
upload_2017-6-6_1-24-51.png

@LSU All you have to do is type in the 6 green cells for the fighters' age, reach, and height (reach and height units don't matter)
and you get your win probability!
 
Last edited:
DC vs. both Rumble and Gus must've royally fucked your system up. Guys like Jacare and Romero are probably pretty unkind to it too.
 
Several posters @DIABOLUS have wondered how this model could be applied toward gambling.
I researched its effectiveness at gambling and came up with some interesting results.
I may post a gambling commentary if anyone's interested.


Also, for those of you wondering if you could do this too, you can. It's uber easy.
I have ALL the information and algorithms stored in an Excel file which I unfortunately cannot upload here for your convenience.
Here's a screenshot.
View attachment 235977

@LSU All you have to do is type in the 6 green cells for the fighters' age, reach, and height (reach and height units don't matter)
and you get your win probability!
Hey Latoya, can you please send your spreadsheet? If yes, pls send a link so I can dl.
Great work btw!
 
Maths, what they are, understand difficults.
 
Rocky Marciano had the shortest reach of any heavyweight champ.

49-0
 
The math checks out. Very interesting stuff!
 
Several posters @DIABOLUS have wondered how this model could be applied toward gambling.
I researched its effectiveness at gambling and came up with some interesting results.
I may post a gambling commentary if anyone's interested.


Also, for those of you wondering if you could do this too, you can. It's uber easy.
I have ALL the information and algorithms stored in an Excel file which I unfortunately cannot upload here for your convenience.
Here's a screenshot.

UFC 214 Odds
View attachment 235977

@LSU All you have to do is type in the 6 green cells for the fighters' age, reach, and height (reach and height units don't matter)
and you get your win probability!

Very cool stuff. You should keep a running log of fight card results and see how well these probabilities match up to the actual results. Keep up the good work!

seinfeld.gif
 
Upvoted for effort. No idea if the math checks out.

<Fedor23>
 
There are to many factors to include and to many factors that we aren't even aware of like injuries, mind set, etc etc.. I could go on for days that only the fighters themselves know whats up.

Plus match ups, training etc etc.. you can't have no reliable formula, it's nice and fun but that's all in the end.

Thanks for the effort, oh last reach in MMA is freaky to me many of this guys don't know how to use it and the others don't know how to exploit or get around reach in terms of striking we have a long ass time to evolve.
 
Back
Top