# Is Ronda's mum really a statistician?

Discussion in 'UFC Discussion' started by casio298, Jul 31, 2015.

1. ### casio298White Belt

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Hello, fellow CFA charters or actuaries. Ronda's mom's comment in UFC 190 Vlog Epi 3 really bugs me.

She said.

"Even if someone has a one in a million chance per second of beating you, if you let it go 60 seconds where you could have done it in ten, you give them six times the chance, that's just stupid"

Now there are three possibility in each second, Ronda wins, Ronda loses or proceed to the next second. Therefore this is basically a Trinomial Option Pricing Model, right?

She implied that the probability of an opponent winning in a 60 second is six times greater than an opponent winning in 10 seconds, that must mean the probability is additive, which is erroneous.

A simpler example, say Bethe has 1 in 1000 chance of winning per second, if it's additive, than that means after 1000 seconds, the Bethe has a 100% chance of winning. Which is not true.

If you do a two step trinomial model starting from the 10th second of round 1, which we denote as t_0, and for the sake of easier of calculation, let Ronda chance of winning per second be 3/10, Bethe winning = 1/10 and proceeding to the next second be 6/10.

probability at t_1, or 1 second after t_0, is 3/10 for Ronda (R), 6/10 going into next second (N) and 1/10 for Bethe (B). Or mathematically, P(R)_1 = 0.3, P(N)_1 = 0.7 and P(B)_1 = 0.1

At t_2, which means they have to go through the previous second, which had a 0.6 probability, therefore P(R)_2 = 0.3 * 0.6 = 0.18, P(N)_2 = 0.6^2 = 0.36 and P(B)_2 = 0.1 * 0.6 = 0.06

etc

At each second, the probability of Ronda beating Bethe is always the same,

At the 60th second, or t_50, Bethe's chance is 0.1 * 0.6^49 = 1.34714 E-12, the cumulative chance from t_1 to t_50 and to the of the match is 0.25 via a KO, TKO or submission for Bethe. 0.25 is not 50 times bigger than 0.1.

I mean she's got a PhD and an expert in SAS apparently, how can she make up statistically incorrect statement?

2. ### George JetsonOrange Belt

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Cool post even though I didn't read most of it.

Maybe someone can tweet this thread to Ronda's mom so we can see the two of you duke it out in this thread for mathematical supremacy.

Popcorn is waiting.

3. ### TSOPink Belt

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Post from your real account dude.

4. ### HockeyBjjPutting on the foil

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I went to college too ts

I'm not an overcompensating dick about it

5. ### Thrawn33JUST BLEED Belt

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Ummm....

WAR Judo

WAR Our Lady of Armbars and her world champ Judo mother.

6. ### Italian BrockBannedBanned

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She's not even a real doctor

7. ### winterbikeGreen Belt

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Ronda's mom is batshit crazy, just like her daughter. A good fit for martial arts.

8. ### Maxi157White Belt

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She has a PHD, but yeah the probability of Ronda winning doesn't dwindle down the longer the fight, I think she was just saying the longer you let Bethe stick around the grater her chance of pulling off an upset, she was just trying to say it in a special way that didn't really pan out but it was a good try.

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11. ### KhabibTheBeagleSilver Belt

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She isn't a statistician, she's a Judo.

12. ### FyrebornBrown Belt

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Trinomial means there are 3 branches at each time step.

What you have shown has only one branch...?

13. ### Chomsky HonkBlack Belt

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Agreed

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15. ### 1rawdogOrange Belt

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laughing my ass off over here, you obviously do not even see the little mistake you made.

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17. ### casio298White Belt

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The two end branches would end the match at each steps... this is not a true trinomial because matches end, share prices don't. Concept is the same. This is the closest model I can conjecture, I'm sure some analysts out there would have a much better model for modelling UFC statistics for betting etc. I just want to disprove Ronda's mom's comment, that's all.

If you have a better model, please elaborate. I know actuaries have contingency table model thingy they use, which might better model the probability.

18. ### RyanMctWrestlerWhite Belt

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TS is a general rutard.

A claim that she has 1/million chance "per second" of beating her that means that every 10 million seconds of competition, she, in theory, would beat her 10 times. In one million seconds we would expect her to beat her one time. Neither of these are guaranteed, but the chance is 10x greater that she will beat her in 10 million seconds than in one million seconds. This can be done with any ratio of numbers.

19. ### roventuBrown Belt

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i think you're right, TS, Ronda's mom should've actually said this in the interview

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