Bracket Style Tournament Racing?

Debates and discussions on the various race scheduling methods that can be used and their fairness and accuracy in determining the winners.
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gpraceman
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Re: Bracket Style Tournament Racing?

Post by gpraceman »

SuperDave wrote:Oops, I just discovered that you edited your post to
My apologies for that. I often write, rethink and edit.
Randy Lisano
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Stan Pope
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Re: Bracket Style Tournament Racing?

Post by Stan Pope »

SuperDave wrote:This looks suspiciously like lanes times the [number of cars minus 1], so you can figure the number of races for other numbers of lanes and cars. 50 racers on a four lane track would be 196 races. (Stan please let me know if I'm wrong.)
Yes, you are. The actual number is 101. See http://members.aol.com/standcmr/nelimsim.html. But that higher reduction factor (4 to 1 instead of 3 to 1) is uninteresting with only 50 cars racing.
Stan
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Re: Bracket Style Tournament Racing?

Post by gpraceman »

SuperDave wrote:50 is not evenly divisible by three or four. In a four lane system, 52 heats will be run by 49, 50, 51 or 52 cars.
With Perfect-N type and Lane Rotation charts (and some others) it ends up being:

#Heats = #Runs Per Lane X #Racers

That is regardless of the number of lanes. There is no need to make it divisible by the number of lanes.

So, essentially you are adding in dummy cars or "Byes" to round out the number of cars to be equal to a multiple of the number of lanes. No problem with that, other than some extra heats to run, just trying to understand how lane equity is being assured.
Last edited by gpraceman on Thu Mar 29, 2007 9:01 am, edited 2 times in total.
Randy Lisano
Romans 5:8

Awana Grand Prix and Pinewood Derby racing - Where a child, an adult and a small block of wood combine for a lot of fun and memories.
SuperDave

Re: Bracket Style Tournament Racing?

Post by SuperDave »

But that higher reduction factor (4 to 1 instead of 3 to 1) is uninteresting with only 50 cars racing.
I'm confused, but it's not all that unusual. More lanes means fewer racers? What is the predictive formula please?
SuperDave

Re: Bracket Style Tournament Racing?

Post by SuperDave »

adding in dummy cars or "Byes"
Actually just empty lanes and [moderator cut - no personal jabs] typically with the slowest cars though no car runs alone.
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gpraceman
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Re: Bracket Style Tournament Racing?

Post by gpraceman »

SuperDave wrote:Actually just empty lanes
Then, I would classify that as a "Bye".
Randy Lisano
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Awana Grand Prix and Pinewood Derby racing - Where a child, an adult and a small block of wood combine for a lot of fun and memories.
SuperDave

Re: Bracket Style Tournament Racing?

Post by SuperDave »

Then, I would classify that as a "Bye".
Fair enough, though in the world of Soap Box Derby racing which is double elimination by AASBD rule, a 'bye' is when a car automatically 'wins' a round and advances without even running. In this case two or more but less than the full track actually run so 'bye' is a little stretch but I see your point.
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Re: Bracket Style Tournament Racing?

Post by gpraceman »

SuperDave wrote:though in the world of Soap Box Derby racing which is double elimination by AASBD rule, a 'bye' is when a car automatically 'wins' a round and advances without even running. In this case two or more but less than the full track actually run so 'bye' is a little stretch but I see your point.
But, we are not discussing SBD. "Bye" has been used to denote an empty lane in the schedule for this type of racing, so I classified it as such.

Now that we've debated the term "Bye", can we get back to the topic at hand?
Randy Lisano
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Awana Grand Prix and Pinewood Derby racing - Where a child, an adult and a small block of wood combine for a lot of fun and memories.
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Re: Bracket Style Tournament Racing?

Post by Stan Pope »

SuperDave wrote:
But that higher reduction factor (4 to 1 instead of 3 to 1) is uninteresting with only 50 cars racing.
What is the predictive formula please?
The actual formula involves integer aritmetic and ceiling formulae and is generally hard to follow through the required iterations. Your best bet is to look at the referenced javascript page and "plug in the numbers" OR inspect the javascript to see the formulae applied.

The reason that I used the term "uninteresting" is that the Group 1 "survivor" runs in fewer competitive heats with higher reduction factors. Here are the group 1 size sequence for various reduction factors, assuming no ties:
5 to 1: 50 => 10 => 2 => 1
4 to 1: 50 => 13 => 4 => 1
3 to 1: 50 => 17 => 9 => 3 => 1
2 to 1: 50 => 25 => 13 => 7 => 4 => 2 => 1

3 to 1 is a good compromise ratio considering total racing time.
Stan
"If it's not for the boys, it's for the birds!"
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