Common Lottery Algorithm
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Anonymous
| OP here -- I think the only fact we have is that the DME office needs to be much better about communicating how the lottery will be run this year. It sounds like when people call (taking them at their word, of course), they are hearing different things, some of which could imply that changing the order of your preferences will give you an advantage, and this could have a big impact on people's lottery choices. I think the DME office needs to have much more clear Q&A about how it all works. |
Anonymous
| I think the problem at this point is not poor communication but too many parents who either never had or flunked their math/stats classes in high school. Get your old textbooks out and look up "separate random drawings". For once, those blowing through savings playing state lotteries will have a leg up at least. Let's hope our kids will do better! |
Anonymous
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Hey, how about we just look at the FAQ on the MySchoolDC site!
http://www.myschooldc.org/faq/#common-3 How does the My School DC common lottery work? Student-school matches are based on the number of spaces at each school; sibling, proximity, and other preferences; and each student’s choices. (Through the My School DC common lottery, the six DCPS specialized high schools admit students based on specific criteria.) When there are more students than spaces at a school, students who have a preference (such as a sibling preference) will be the first to be offered spaces. Then, random selection decides which other students will be offered spaces. Students will be matched with no more than one school. My School DC will try to match each student with their 1st choice, then their 2nd choice, and so on through the student’s list. **** Oh look, preferences matter! |
Anonymous
Good, we're all on the same page that **nothing** about what a parent does changes, no matter who is right. That is what the vast majority of us care about. At least some people are clear that they are simply reporting what they heard. Frankly I respect that PP for not actually saying this is "fact", but saying this is what s/he heard. Are you saying you know what s/he heard when they called, and that you have a basis for calling them a liar? Someone above posted the lottery phone number. Anyone who cares about what you and PP are arguing about needs to call. |
Anonymous
Preferences matter. Preferences are defined: "Students with a preference at a particular school are offered space at that school before students who don’t have a preference. There are four types of preferences: sibling preference (DCPS and charters), proximity preference (DCPS only), in-boundary preference (DCPS PK3 and PK4 only), and Adams-boundary preference (Oyster-Adams Bilingual School only)." Preferences in this sense have nothing to do with rankings on your lottery list. Reference: http://www.myschooldc.org/getting-started/what-do-all-these-terms-mean/#pref |
Anonymous
| this is starting sound like the same method we used for matching for sorority rush. But not as organized as sorority rush. |
Anonymous
Which means what? How does this affect how I choose to rank? Do I now not need to put my true #1 school as #1? What does you pointing this out mean? Also, just out of curiosity, where in this 9 pages of comments did anyone say preferences didn't matter? I see people arguing about which things give you a preference and how the process will handle preferences, but where does anyone say preferences don't matter, as you clearly think someone has said? |
Anonymous
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Of course preferences matter, but not during the randomized and separate drawings; they matter in the next step, namely if and when you happen to have gotten two or more "accepted". Only the most preferred (highly ranked) of those will be granted. And that better be your preference!
(Sounds like some shortfall on the part of parents not only when it comes to their lessons in stats and probabilities but also when it comes to reading comprehension. Maybe time to stop complaining about lagging CAS scores in DC schools...) |
Anonymous
For an individual family, the best strategy for ordering your picks changes upon which algorithm is being used. There are two competing ideas being proposed here: 1. that the order of your ranking affects the weight given to your pick; and 2. that the order of your rankings does not affect the weight given to your pick. For brevity, I will refer to #1 as the "incorrect" idea and #2 as the "correct" idea. Under the correct idea, there is no advantage in doing anything other than ranking your picks in the order of your actual preference. The only time you should even consider your odds of getting into a school is if there are more than 12 schools that you would consider going to, in which case you have to consider whether including a school that you have a near-zero chance of getting into means leaving off a 13th school that you would attend if you got into it. Under the incorrect idea, you have an edge getting into your highest ranked school. If you use that pick for a school where you have zero chance of getting in, you have wasted that edge. The optimal strategy is to use that edge where it is most likely to help you, which is a school where you are likely to get in with the edge and unlikely to get in without it. It doesn't matter if that is in fact your number one choice. This strategy involves knowing something about your relative chances of getting into each school, which you can derive from looking at last year's results. It also involves knowing something about the size of the edge. Since the edge doesn't exist, that information is impossible to obtain. |
Anonymous
There is only one drawing. |
Anonymous
I hope someone prints this post out and faxes it/emails it to the lottery and asks them which algorithm is correct, or at least which premise about the importance of ranking is correct. I may bring it with me to the Expo because I'm sure they'll be there. |
Anonymous
I think the folks at the lottery have a real issue with not wanting to say clearly how the lottery works. Consider this sentence from the FAQ:
Clearly this is consistent with the "correct" idea, but if you believed the "incorrect" idea it would be easy to read this as supporting that as well. |
Anonymous
There is someone posting all day who has been saying that preferences are ignored and only the ranking by the parent/student matters. Since you have the reading comprehension of a 3 year old I assume that someone is you. |
Anonymous
The problem is both ideas you are talking about are wrong. The washingtonpost article written about myschooldc links to a site that pretty clearly states that the order of your rankings DO MATTER and the preference that the school provides ALSO MATTERS. Last years results mean nothing. What matters is the pool of applicants from this year. What matters is whom is selecting a particular school and how that particular school is ranking that child. Think of it like this: Child A Rankings 1 - School A 2 - School C 3 - School B Child B Rankings 1 - School B 2 - School C 3 - School A Child C rankings 1 - School A 2 - School B 3 - School C Now each of those schools rank you School A 1 - Child C 2 - Child A 3 - Child B School B 1 - Child A 2 - Child B 3 - Child C School C 1 - Child A 2 - Child C 3 - Child B What we can infer above is IF child C selected School A as their #1 choice then Child A has ZERO change of getting into that school because Child C is both their #1 choice and requesting that school as his/her #1 choice. |
Anonymous
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con't from above.
The school based rankings are a combination of the pool of their prefrence and their randomly assigned number. |