TransWikia.com

Real life problem: How many finalists can participate per school?

Mathematics Asked by math2hard on February 8, 2021

I have to organize a tournament with following numbers:

I have a total of 1338 participants from different schools, and we need to distribute the 16 finalist’s places as fair as possible.

The students are distributed as follwing:

School and number of participiants
a 254
b 211
c 150
d 186
e 158
f 85
g 66
h 105
i 123

Every school gets at least one finalist. How do I distribute the 16 final places to the different school?

Thank you so much for your help!

2 Answers

The assignment $(3,3,2,2,2,1,1,1,1)$ is optimal for each of the following three objectives:

  • Minimize sum of absolute differences between number of seats and quota
  • Minimize maximum of absolute differences between number of seats and quota
  • Minimize sum of absolute differences between people per seat and $1338/16$

Answered by RobPratt on February 8, 2021

It seems natural to assign the places roughly proportional to the number of students. Then again, this might easily leave school with $0$ finalists. And we have to deal with rounding. So the next natural thing is to assign $$ lfloor alpha n+betarfloor$$ finalists to a school with $n$ students. Remains to pick $alpha$ and $beta$. Typically, one fixes one of them and adjusts the other (e.g., by trial and error) until $$ sum_{i=1}^9lfloor alpha n_i+betarfloor =16.$$ Different strategies are possible (and some correspond to vote counting methods commonly in use to distribute parliamentary seats according to vote counts):

  • Set $beta=0$ and adjust $alpha$. This method tends to favour large "parties" and may not lead to a "seat" for the smallest school here
  • Set $alpha=frac{16}{sum n_i}$ and adjust $beta$. This method assigns the naive average as "cost" of a seat and adjusts the offset $beta$ to make the first seats cheaper until the sum is right
  • Set $beta=1$ and adjust $alpha$. This is essentially like the first, except that every school gets one seat for free to start with.
  • Set $beta=frac12$ and adjust $alpha$. This is somewhere between first and third option
  • ...

Answered by Hagen von Eitzen on February 8, 2021

Add your own answers!

Ask a Question

Get help from others!

© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP