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Praise for The Basketball Distribution:

"...confusing." - CBS
"...quite the pun master." - ESPN

Conference Bias in the Polls: No Mountain-West Love


"The Nation's Best Point Guard" apparently.

I did a very quick study on how conferences/teams are underrated or overrated in the polls.

First, I combined the ESPN and AP Polls from Monday.
Here's a simple formula based on regression to add the vote totals from both polls for NCAA basketball:

Total Adjusted Votes= AP votes + (2*ESPN Votes+26)

The top-27 in this method is shown left.

All teams worse than #27 were given a simple "#40" as a placeholder . I then compared each of these team's rankings to my own ranking system, which is very similar to Ken Pomeroy's...I can just fiddle with it as I please :). From this, it's pretty easy to see that teams that have won a lot of close games are overrated and vice versa (if you trust us stat-geeks on the principle of 'luck').

To convert Luck (Win% - Expected Win%) to ranking deviation (Poll rank - my rank), I found the following easy equation:
Expected Ranking Deviation = 140 * Luck% - 0.38

So for each conference, I found the average luck of my top 49 (I stopped at 49 because that's where Murray is ranked) and found the following. I split the rankings into three categories

-Murray State (the only OVC team here, and the most overrated team in the country)
-Conferences (with at least 2 listed teams in the poll)
-Other Conferences (the total of each of the conferences with one bid)
 

Like so:


#Top 40 Avg Luck
Murray State10.138
A1020.016
WCC30.009
MVC20.004
Other Mid-Majors5-0.002
BE9-0.002
MWC2-0.007
B126-0.012
ACC5-0.014
P122-0.033
B106-0.040
SEC4-0.048

Then I used the Expected Ranking Deviation formula to come up with each 'conference's average expected ranking deviation:


#ExpRkDiff
Murray State118.9
A1021.9
WCC30.9
MVC20.1
Other Mid-Majors5-0.7
BE9-0.7
MWC2-1.4
B126-2.0
ACC5-2.4
P122-5.0
B106-6.0
SEC4-7.1


Then I simply subtracted each team's Expected Ranking Difference from their Actual Ranking Difference to give us an estimate of conference bias. The results are pretty intuitive:


#Top 40 LuckExpRkDiffActualRkDiffBias
Murray State10.13818.933.014.1
B106-0.040-6.0-2.04.0
BE9-0.002-0.73.03.7
ACC5-0.014-2.41.23.6
SEC4-0.048-7.1-7.00.1
WCC30.0090.9-0.7-1.6
MVC20.0040.1-1.5-1.6
B126-0.012-2.0-4.3-2.3
P122-0.033-5.0-8.0-3.0
Other Mid-Majors5-0.002-0.7-5.4-4.7
A1020.0161.9-6.5-8.4
MWC2-0.007-1.4-12.0-10.6

The only real surprise to my eyes is the Big 12 having a bias of -2.3. Murray State is overrated by their ridiculously easy schedule which they haven't beaten to a pulp. The only four other overrateds are the rest of the power conferences minus the Pac-12, who is still in "recovery mode."

2 comments:

  1. to bad you did all that work to be wrong. Mountain West isnt good in the tourney! period!!! your nerdery doesnt add up

    ReplyDelete
  2. This post was done in 2012, son.

    ReplyDelete

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