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[quote=Anonymous][quote=Anonymous][quote=Anonymous][quote=Anonymous]The school rankings made by other parents/student have absolutely no affect on your capability of accepting a seat in the lottery.  The only thing has an affect on your acceptance is as follows:

1) Someone with a better preference requests the same seat
2) You get accepted at a higher ranked school.

That's it.  It doesn't matter what the rank of the school was in scenario #1.  The algorithm ignores it.  It's entirely possible that the kid accepted in scenario #1 moves on to another school (that he ranked higher) and you can get the seat back!  That's how the algorithm works![/quote]

Source?  What is your source that in this specific situation it works this way?[/quote]

This was all linked to earlier in the thread

Post article about MySchoolDC
http://www.washingtonpost.com/local/education/dc-rolls-out-unified-enrollment-lottery-for-traditional-charter-schools/2013/11/19/448ee1e0-4ca7-11e3-9890-a1e0997fb0c0_story.html

Which talks about Al Roth, nobel prize wining economist and chairman of IIPSC, the company running the lottery
http://iipsc.org/

The publication page leads to an article about the New Orleans Lottery
http://www.nola.com/education/index.ssf/2012/04/centralized_enrollment_in_reco.html

Which contains this image giving the steps on how the algorithm run
http://media.nola.com/education_impact/photo/diagram-enrollment-041512jpg-aea0b995c0aa929b.jpg

Pay special attention to step 3, because that's the crux of it.  You are ranked by your preference pool and your random lottery number.  Your school ranking only comes into play after step 3.  The whole thing loops until it can't do any more matching.

If you really want to read up on it, here is an academic paper also published on the IIPSC website:
https://www2.bc.edu/~sonmezt/sc_aerfinal.pdf

[/quote]

I've reviewed most of those, including step 3.  It amazes me that so many of you completely don't get that the specific example we're talking about is not outlined in Step 3.  The example, for the zillionth time, is:

Student A has sibling preferenc at school A but ranked it #3.  Student A's randomly assigned lottery number is 10.  Student A has no other preferences (adding part about lottery number and no other preferences just to further clarify the question).  By the time Student A is being considered for school A, they have already not gotten spots at their 1st and 2nd choice schools.

Student B also has sibling preference at school A but ranked it #1.  Student B's randomly assigned lottery number is 20.  Student B has no other preferences.

Show me the official source that says either: "Student A will get the spot because their random lottery number is higher"  or "Student B ranking school A will NOT give student B an advantage over Student A".

Don't just link, show the specific place where it is clearly stated/explained that Student A trumps B no matter what in this scenario.[/quote]

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