Common Lottery Algorithm

[Anonymous]

Anonymous wrote:

Academics (special high schools) and address (dcps proximity) are certainly factors in your lottery placement in the algorithm.

The special high schools are application-only, they don't use the lottery.

For proximity, you're either in-boundary or you aren't, and you're either within walking distance or you're not. The thing about the lottery is there is no nuance. Everyone who is in-boundary is ahead of everyone who isn't.

[Anonymous]

I have a feeling the line at myschoolsdc on 1/11 will be long.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

There is no such thing as "merit based" preference in the DC lottery.

As to whether "the algorithm deems it as a better match" -- DC has a strict priority system. There are seven tiers of preference, everybody is in exactly one tier for any given school, if you're in a higher priority tier than someone else, you get the seat, they don't. Charters are allowed to set their own tiers but the same principle applies.

[Anonymous]

Anonymous wrote:I actually don't think it's that complicated, it's just the misinformation that's confusing matters.

I agree that it's not that complicated. I think that wishful thinking is confusing matters. There is a strong human desire to feel in control of your fate. People really wish that there was some way that they could control the outcome of the lottery by managing their picks shrewdly. You can't. Order your picks in your actual order of preference.

[Anonymous]

Anonymous wrote:

Anonymous wrote:I actually don't think it's that complicated, it's just the misinformation that's confusing matters.

I agree that it's not that complicated. I think that wishful thinking is confusing matters. There is a strong human desire to feel in control of your fate. People really wish that there was some way that they could control the outcome of the lottery by managing their picks shrewdly. You can't. Order your picks in your actual order of preference.

Agreed, there is no way to "game" the system, it is designed that way.

[Anonymous]

Anonymous wrote:So if my child has no preferences anywhere we apply, the best we can hope is an early lottery number and enough open (non IB, non Sib) spaces at one of our top 3-5 schools? And if our lottery number is at the end of the pack, we will basically be shut out of all but choices 11 or 12 and at the end of most wait lists?

So one thing that confuses me about this whole conversation is, did something change at the charters in terms of defining "open/available slots"? Last year all the charters I cared about accounted for sibling slots BEFORE reporting/finalizing how many "available slots" would go to lottery. So if the slot was lotteried at all, it went to non-sibs.

Did that change? I do understand that if the school only has 10 open slots and 20 sibs who want it, they need to have a sib-only lottery, and I can see how this year those sibs who didn't get a slot would have to apply through the common lottery to fight it out for those few spots or their waitlist positions. But did that change? Are all sibs now entering the common lottery and no spaces are filled with sibs before the lottery?

[Anonymous]

PP, all sibs have to enter through the lottery. For charters sibs have preference, so assuming there are more places in a grade than applicants with siblings at the school sibs get in regardless of lottery number. If there are more sibs than spaces, sibs are ordered by lottery number. In effect it's the same as last year.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Academics (special high schools) and address (dcps proximity) are certainly factors in your lottery placement in the algorithm.

The special high schools are application-only, they don't use the lottery.

For proximity, you're either in-boundary or you aren't, and you're either within walking distance or you're not. The thing about the lottery is there is no nuance. Everyone who is in-boundary is ahead of everyone who isn't.

Special high schools are part of the lottery this year. Read the FAQ.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

There is no such thing as "merit based" preference in the DC lottery.

As to whether "the algorithm deems it as a better match" -- DC has a strict priority system. There are seven tiers of preference, everybody is in exactly one tier for any given school, if you're in a higher priority tier than someone else, you get the seat, they don't. Charters are allowed to set their own tiers but the same principle applies.

There are merit based preferences for 6 high schools in this lottery.

[Anonymous]

Anonymous wrote:So if my child has no preferences anywhere we apply, the best we can hope is an early lottery number and enough open (non IB, non Sib) spaces at one of our top 3-5 schools? And if our lottery number is at the end of the pack, we will basically be shut out of all but choices 11 or 12 and at the end of most wait lists?

Be sure that you are really okay with sending your child to any of the schools on the list, because I imagine that lots of people are going to freaking out when they see they got a spot at their #10 school. Good luck, friends.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

There is no such thing as "merit based" preference in the DC lottery.

As to whether "the algorithm deems it as a better match" -- DC has a strict priority system. There are seven tiers of preference, everybody is in exactly one tier for any given school, if you're in a higher priority tier than someone else, you get the seat, they don't. Charters are allowed to set their own tiers but the same principle applies.

There are merit based preferences for 6 high schools in this lottery.

yes, the lottery application for the 6 high schools includes an on-line portion (you fill out the form and then you have to upload a PDF of scores and grades) and also another portion that may be an audition or a test or interview. If you satisfactorily pass those two portions per what the school requires then you are accepted for those schools and will be offered placement.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

The problem with stating it this way is that it seems to allow for gaming of the system still. If, after preferences are taken into account, a student is geographically closer to a school than another student and has ranked it higher, the algorithm WILL NOT take the seat away from the student who is further away and has ranked it lower.

If it were the case that the rankings and the geography will ne taken into account by the algorithm (AFTER preference is accounted for) then there WOULD be an incentive to rank a desirable neighborhood school higher than a desirable charter across town on your list and there IS NOT an incentive to do that.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

The problem with stating it this way is that it seems to allow for gaming of the system still. If, after preferences are taken into account, a student is geographically closer to a school than another student and has ranked it higher, the algorithm WILL NOT take the seat away from the student who is further away and has ranked it lower.

If it were the case that the rankings and the geography will ne taken into account by the algorithm (AFTER preference is accounted for) then there WOULD be an incentive to rank a desirable neighborhood school higher than a desirable charter across town on your list and there IS NOT an incentive to do that.

This makes no sense. You are missing that how badly the student wants that school is also part of the matching. A student who ranks the school less than 1 does not want it as much as a student who ranks it 1. There is a random draw initially, but once it's sorted by preference, there is further sorting within preference groups for who really wants that school. That is NOT gaming. It is part of the 2-way matching.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Or I should state - your ranking doesn't have an effect on your placement. It has an effect in that they go down the list so your first school is the first to give a seat if available, but your ranking DOES NOT INCREASE YOUR PROBABILITY OF GAINING A SEAT.

It most certainly does. You will not steal a seat from a higher preferenced child if that match is more equitable for both parties. That's the whole point of deferred placement! Youre given a seat but it can be taken away and given to someone else if the algorithm deems it as a better match - and that match takes into account both child's assigned preferences, whether they are location based, merit based or sibling based.

The problem with stating it this way is that it seems to allow for gaming of the system still. If, after preferences are taken into account, a student is geographically closer to a school than another student and has ranked it higher, the algorithm WILL NOT take the seat away from the student who is further away and has ranked it lower.

If it were the case that the rankings and the geography will ne taken into account by the algorithm (AFTER preference is accounted for) then there WOULD be an incentive to rank a desirable neighborhood school higher than a desirable charter across town on your list and there IS NOT an incentive to do that.

This makes no sense. You are missing that how badly the student wants that school is also part of the matching. A student who ranks the school less than 1 does not want it as much as a student who ranks it 1. There is a random draw initially, but once it's sorted by preference, there is further sorting within preference groups for who really wants that school. That is NOT gaming. It is part of the 2-way matching.

+1.
Look up "student-proposed deferred-acceptance model" for more information.

[Anonymous]

I did, and my understanding is that is not the model we are using (the NYC/Bost model differs from the Denver model which differs from the New Orleans model.)

Explain this, if the ranking matters in that ranking a school higher gives you a better chance of getting in, is there not an incentive to put a "safety" higher on the list then?