
Why Ken Jennings’s ‘Jeopardy’ Streak Is Nearly Impossible to Break - mblevin
http://fivethirtyeight.com/features/ken-jenningss-jeopardy-streak-is-safe-for-the-rest-of-time/
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monochromatic
> So we (or, more precisely, FiveThirtyEight’s lead lifestyle writer Walt
> Hickey) ran a simulation that flipped a weighted coin with a 97.9 percent
> chance of landing on a Jennings win. Every time it did, we “flipped the
> coin” again. We did 1 million of these simulations.

This is just a binomial distribution. Did they seriously estimate the answer
instead of solving it analytically?

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jdoerrie
Given that we stop after the first failure technically this should be a
negative binomial distribution
([http://en.wikipedia.org/wiki/Negative_binomial_distribution](http://en.wikipedia.org/wiki/Negative_binomial_distribution))
with p = 0.979 and r = 1. The mean is p / (1-p) = 46.62. Also there is a p ^
75 = 0.204 chance that someone of same skill will achieve a better score.

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jMyles
It never occurred to me that optimized buzzer timing was such a big part of
Watson's dominance. Kinda takes some of the romance out of it.

~~~
gamegoblin
Something I never liked about jeopardy is that you can't buzz in at any time.

I played on a trivia team at the high school level, and most questions were
structured like:

"This American architect, born in 1867, is known for works such as the Robie
House, the Guggenheim Museum, and Fallingwater."

So they typically feed you information from least to most well known, and you
can buzz in at any time. This rewards players who know the most trivia.
Everyone who played knows Frank Lloyd Wright did Fallingwater, but a very good
player would know his approximate date of birth and would buzz in immediately
on hearing 1867.

I understand that this might make Jeopardy less fun for the audience, but I
feel it would be a better test of trivia instead of buzzer timing.

~~~
fsk
They made it that way on purpose, so it's more entertaining for the audience.
If you could buzz in early, the players would almost always buzz in before
Alex Trebek finished reading the question, which makes it less interesting for
the audience.

With the wait-to-buzz-in rule, the audience gets an chance to understand and
maybe think of the answer before the contestants speak.

~~~
curun1r
You could allow contestants to buzz in as soon as possible, but have the
system wait until Alex has finished reading the answer (remember, it's
Jeopardy! so the contestant gives the question ;-P) before it indicates which
player buzzed in first. Yes, there might be an audible clicking sound in the
background while he's talking, but it would make the game more about speed of
recall rather than hand-eye coordination.

~~~
kmkemp
I think that would just encourage contestants to buzz in immediately, since I
imagine that the risk of penalty of not knowing a question pales in comparison
to the reward of getting to answer for a strong contestant. You effectively
eliminate the only downside of buzzing early since contestants would get to
hear the entire question regardless.

~~~
fennecfoxen
The traditional College Bowl <TM> / Quizbowl <not-TM> technique is (a) to
assign a 50% penalty to the early buzz with an incorrect answer, and (b) since
it's game with teams and has two teams, the rest of your team is disqualified
from answering the question, leaving the opposite team with lots of time to
think about it (and subsequently secure access to the 3x bonus question
following every toss-up question.)

Which is lots of fun and very competitive, but a little bit less tele-savvy.

~~~
colomon
Ack, we ran up against a "celebrity" reader in the final rounds of a Quizbowl
tournament who didn't stop reading reliably when the other team buzzed in. I
don't know how, but the other team was really good at taking advantage of
this, buzzing in before the reader had given enough information to answer the
question, and then answering after he'd finished the sentence. Our team got
steamrolled.

~~~
gamegoblin
In Highschool Quizbowl, I'd take advantage of the fact that most untrained
readers have a hard time stopping mid-syllable, or even mid-word, so any time
there was a question that hinged on a single word, such as a world capital
question, I'd buzz in on the first letter of the word, and they'd usually get
out 2 syllables before stopping, providing enough information.

Q: What is the capital of L-(BUZZ)-ithu-- [stops reading].

A. Vilnius.

But if they had had really good reaction time and stopped on L--, I'd have
been hosed. Latvia, Lithuania, Liechtenstein, Libya, Liberia, etc...

~~~
colomon
The team that beat us was doing more

Q: What is the capital of (BUZZ) Lithuania?

A: Vilnius.

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Steko
> _Here’s how we figured this out. We assumed that Jennings headed into Final
> Jeopardy with at most one other player in contention to win. Then we assumed
> that in order for Jennings to lose, this sequence of events has to happen:
> The game must not be locked up, Jennings must get the Final Jeopardy
> question wrong, and the other contender must get it right. We used his stats
> across all 75 of his games, not just his 74 wins, to better reflect his
> overall skills. The probability he doesn’t have the game locked up is 13.3
> percent, the probability he gets Final Jeopardy wrong is 32 percent, and the
> probability the other contender gets it right is 49 percent. When we combine
> these probabilities, we see that Jennings only has about a 2.1 percent
> chance of losing._

This is incorrect and overstates his dominance because (1) it assumes Jennings
will be ahead, something that won't always happen against
Rutter/Jennings/Collins/Chu/Craig level players and (2) the lock up and
opponent knowing Final Jeopardy conditions are not independent.

Pretty sloppy basic probability by 538 and make me think I'm not missing much
by not subscribing (they didn't offer full RSS last I checked).

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Aushin
When you say that they're not independent, do you mean that the probability
that the person knows the Final Jeopardy question is higher because they've
managed to keep Ken Jennings from running away with it (i.e. they're better
than the average person Jennings has faced)?

Just checking my understanding.

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datashovel
I'm convinced that not only do we stand on the shoulders of giants, but we
live among giants. What Ken Jennings accomplished is remarkable by any
interpretation. How he did so probably even he can't explain.

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ilaksh
Unless you're a computer.

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martin1975
Ken Jennings' 74 win streak is because...?

A. He cheated B. He's lucky C. He's a genius D. It's written

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jplarson
Seems harsh that so many people downvoted this, I dig the Slumdog Millionaire
reference!

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axitanull
I believe that is because many people don't want comment section in Hacker
News turn into the one in Reddit, which consist of mostly jokes, pop culture
references...things that doesn't really contribute to the discussion.

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jplarson
Got it, thanks!

