
Radial NCAA Bracket in D3.js - hox
http://billmill.org/roundbracket/
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dmsimpkins
I love the look of this, but I have one suggestion to make. If the probability
for a particular round is < 1%, I would at least leave one decimal place or
show "< 1%" instead of having 0%, since obviously there is still some chance
of the team making it to that round, even if it's a fraction of a percent.

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jader201
A bit off topic, but I find it odd how the 16-seed teams are calculated at
between 1-4%, even though no 16-seed team has made it past the first round in
the entirety of the 64-team tournament (1985: 29 years x 4 teams = 0 for 116).

Not sure how any of these have more than a <1% chance, let alone 4%.

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llimllib
The usual method for calculating these percentages is to calculate a power
rating for each team, then to use the log5 formula[1] to arrive at the
percentage chance of a team winning.

So, the 1-4% chance of a 16 winning is the result of applying the log5
algorithm to their power ratings.

Also remember that there's only 80 16-vs-1 games in 20 years, and only
expanded to 64 teams in 1985, so it's totally possible that there is a 1-4%
chance for a 16 to beat a 1 and it just hasn't happened yet.

[1] [https://en.wikipedia.org/wiki/Log5](https://en.wikipedia.org/wiki/Log5)

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bertil
I love the presentation.

If I can be a complete jerk, but improvement is based on feedback, etc., a
couple of modifications:

* edit the lower values (2% or less, especially at the center) to reflect unlikely but possible events: most people (rightfully) assume that 0% means: not possible, as in, against the laws of nature. Very unlikely is more 0.1 or 0.01%; it’s a huge hassle, but from experience those are worth all the days spent on that -- I've done it enough times in LaTeX, R and D3.js to know…

* use the team colors for the tone; it's cheesy, but fans would love that;

* use the likelihood to reach that point as an opacity factor: opacity is a fairly intuitive way of expressing something.

Finally, if you want newspapers to re-use it, make version with a black and
white background. Yes, I should do all that myself, rather than comment… Yes,
it would be easier for you all to comment before I gather the courage and try.

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1wheel
D3 has a nice formatting helper functions:

    
    
        > d3.format('.2%')(.223)
          "22.30%"
    

[https://github.com/mbostock/d3/wiki/Formatting](https://github.com/mbostock/d3/wiki/Formatting)

It'd also be cool if mousing over the inner circle updated the coloring of
teams, showing their probability of reaching a certain game.

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bertil
Indeed — but the thing is to make that conditional with the size of the number
and not mess up with the layout. Doable, but it's the kind of thing that makes
a great presentation hours away from a usable one.

As for the highlight… Yes, I though about that, but it makes things
complicated: you have to decide what threshold to cut, and sport team fans are
very passionate, so that would ostracise the remaining teams.

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jader201
Am I the only one that was hoping I could fill in the bracket by clicking on a
team to see the probabilities of different matchups (vs. the overall
probability of each individual team for each round)?

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llimllib
Nate Silver doesn't make that information available... I'm considering writing
code to calculate that information from the odds he gives.

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k0mplex
please do. would be awesome to see.

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callmeed
Cal Poly at 0% ... _So you 're saying there's a chance!_

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scott_karana
Looks awesome, but there are a few simple questions this makes really hard to
answer without experimenting with mouseovers.

"Who are the likely contenders?"

"What are some of the closest games between big contenders we will enjoy?"

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latraveler
Great stuff. I wish this was posted yesterday before I filled out mine.

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yeukhon
Textual explanation would be helpful...

