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Dottir takes November TAZD.
skrumgaer wrote
at 9:57 AM, Thursday December 1, 2011 EST
The TAZD and baseball-style standings are explained on my Wall. At least 35 regular games played in the month are require to qualify for the monthly TAZD. Shown are Games Behind, TAZD, and player name.

GB TAZD Player
06 12178 dottir
13 11141 Emre Oguz
03 10171 masticore
00 9719 Invola
39 9539 Shevar
03 8878 OneShot7
18 8842 jona_vicente
06 8419 savif
22 8352 [Ocean]Flushed
32 8336 Mazaman
02 8224 toms
10 8170 what_up23
47 8155 jfdis
08 8113 @ata
24 8064 Az_Balu
17 7666 kostur
20 7604 L3xy
48 7603 bcmatteagles
16 7600 22-Apr
11 7427 Lady Lite
07 7406 Vollhonk
66 7294 Scabbard
26 7159 kdiceplaya!
22 6840 chaiNblade
29 6829 IFIGENIUS
17 6518 FPP
24 6504 _smile_
69 6474 Remiel
43 6441 Simmo3k
40 6411 Mercantile
12 6397 xjxaxnx
11 6328 @Toomyfriends
93 6315 franklyghost
14 6259 Bu7Ch3r
34 6214 fish28
18 6129 Free Flags
19 6043 hcdug
24 5928 kudoukun
18 5921 ovbogaert
14 5907 peter luftig
36 5658 @engr2002
49 5588 EddyB
22 5474 @MikeTamburini
31 5398 Brighty
30 5333 fearlessflyer
39 5281 Lord Death
92 5210 Loobee
35 5123 Gurgi
66 5087 barmat
21 5065 joero14
66 5054 Jily
40 5044 hatty
33 4952 longpube
32 4921 NikkeKnatterton
29 4841 scarp8
54 4794 stackshotbilly
34 4784 OviloN
66 4733 Silesia
100 4730 axlehammer
45 4623 mrb2097
47 4600 nexon
21 4582 Volvic
23 4484 beatol
33 4471 Fatman_x
25 4411 KDancer
41 4306 xXxJozefxXx
25 4289 Keeley
26 4019 euphrates7
87 4003 Rsquared
36 3917 Poker Style
48 3808 "MC"
34 3760 haloducks
41 3641 bivo
69 3261 orestis85
52 3201 greekboi
73 3179 cool g
33 2960 MNK10
57 2817 Trkz
58 2784 greenman
65 2759 These tards suck
76 2714 GreGGwar
70 2500 absolutgimlet
61 2463 Johnboat
44 2285 Kingofskillz
84 2218 DonnieScribbles
93 2208 GR3ENMAN
73 2028 CCSKAOT
94 1253 Kdot
92 1248 ji-jo

« First ‹ Previous Replies 151 - 160 of 161 Next › Last »
superxchloe wrote
at 2:20 PM, Sunday December 4, 2011 EST
Okay here we go. This is gonna be fun, isn't it? I started this last night, so consider it a direct response to your post from 11:49pm:
"If you use the distribution of percentages rather than the distribution of incidences, there is no multiplier, but to compare distributions of different sample sizes (number of games) you have to *multiply* them by their standard deviations. This is all explained on my Wall."

Right. On your three year old wall of technobabble which I have trouble following as a math major. Lemme take a look at that.

"The Test Against Pure Luck (TAPL) is a measure of skill that eliminates the random fluctuations that are characteristic of the game-by-game scoring system and rewards players who play more games. "
We've all agreed at this point that it's a measure of deviation by its pure nature.

"In math jargon, the TAPL is a Pearson?s chi-square goodness of fit test against a uniform distribution."
No it isn't. You don't actually run the test. You just find the chi-square statistic. Not quite the same.

"The TAPL is the normalized sum of seven numbers. The first number is found by taking the difference between the expected number of first-place finishes and the actual number of first-place finishes, given the number of games played, squaring this difference and dividing it by the expected number of first place finishes. The second number is obtained by doing the same calculation for the second-place finishes. The third number is for the third-place finishes, and so on for all seven levels of finishes. The sum is then divided by the square root of the number of games played to get a result expressed in standard deviations."
A chi-square gof is simpler than that- there's no division or multiplication by standard deviation. It's just sum(((observed-expected)^2)/expected). that's it. that's all there is.

"The mean of the chi square goes as the number of games played, and its variance goes as the number of games played"
mean goes by k and variance goes by 2k, where k is the number of degrees of freedom- which is NOT determined by number of games played. It's 6. Number of categories minus one.

So if you decide to convert the percentages to expected COUNTS instead, your formula would be something like this:
http://i.imgur.com/mJyGe.png

... I think that's a good stopping place for now. There'll be more later, kids, don't you worry.
jurgen wrote
at 3:12 PM, Sunday December 4, 2011 EST
great! I was about to play a game after reading this but I will have to wait ten minutes. Reading your post short circuited my mind.

jk, I understand the most part of it

and well done
greekboi wrote
at 3:36 PM, Sunday December 4, 2011 EST
oh man, so much animosity! verm-chloe really hates skrum, and vice versa
skrumgaer wrote
at 4:50 PM, Sunday December 4, 2011 EST
It is the central limit theorem that says that as the number of samples increases, the Pearson's chi square goes to a normal distribution whose mean goes as the number of samples and whose variance goes as the number of samples.

The TAZD is not testing whether a player's distribution is significantly different than the null hypothesis; it is a way of comparing players with different numbers of games. So that is why the totals have to be scaled by the square root of the number of games.

To recapture the actual chi-square statistic of a player, divide the player's TAZD by 1000 and multiply by the square root of the number of games. Dottir, for example, has a TAZD of 25137 and has played 6652 games. Her chi-square statistic is 2050.16. For six degrees of freedom, the chi-square test is 12.59 for p = 0.05, 16.81 for p = .01, and 22.40 for p = .001. So Dottir's profile rejects the null hypothesis. If she had had the same profile but with only 66 games, her chi-square would be 204.2 which would still be significant. For a reasonable minimum number of games, we don't have to worry about whether an individual player's profile is statistically significant.
superxchloe wrote
at 6:07 PM, Sunday December 4, 2011 EST
"The TAZD is not testing whether a player's distribution is significantly different than the null hypothesis"
-> the TAZD isn't a Pearson's chi square goodness of fit test. Which is in fact precisely what I said.

The same size isn't about significance- that's not even being brought into question here.

Central limit theorem states that as k approaches infinity for a chi-square distribution, the distribution of (X-k)/sqrt(2k) tends toward the normal. where k is DEGREES OF FREEDOM which is NOT determined by sample size for a pearson's chi square.
skrumgaer wrote
at 6:33 PM, Sunday December 4, 2011 EST
The central limit theorem says that as the number of **samples** from a distribution increases, the mean of the samples approaches a normal distribution even if the original distribution is not normal. Look at the third line in the first paragraph under the heading Classical CLT from this site:

http://en.wikipedia.org/wiki/Central_limit_theorem

and observe the variance of the mean in the expression.
skrumgaer wrote
at 7:01 PM, Sunday December 4, 2011 EST
In that article, k is the number of observations, not the number of cells. In some of the other Wikipedia articles, the number of observations is referred to as n. So, for a large number of observations, the central limit theorem kicks in, as it is supposed to.

Nice try, though.
superxchloe wrote
at 7:12 PM, Sunday December 4, 2011 EST
In that article k is degrees of freedom.
skrumgaer wrote
at 7:20 PM, Sunday December 4, 2011 EST
which is not relevant here because we both agree that the Pearson's chi square used in the TAZD has six degrees of freedom.

We both should agree that the number of observations is equal to the number of games, and what triggers the central limit thorem is the number of observations.

So the central limit theorem holds, and you have to deal with it.
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