Common Lottery Algorithm

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

7) whenever a student gets an acceptance into a higher ranked seat (1 over 2, 3 over 5, etc), the previous seat (from a lower rank) is added back into the pool of seats for that school/grade (this is where the student/parent school rankings come into play)

This is the part where I get confused - can anyone clarify? Why would a previous seat be added back?

In the example above - if you didn't get your #1, #2, or #3 seat you could theoretically be seated in #4. If #1 open up (say a child who previous had it ranked the school at #2 and they got into their #1 later in the cycle) then you could ask for that seat again and be granted it because you are now the preferred student. Technically you lost #4 and gained #1. If you were to lose that #1 later in the algorithm then you could ask for #4 again and most likely get it back. This is called "deferred acceptance" and the trickiest part of the lottery to explain.

Under what circumstances would you not get the #4 seat back? If the seat was taken by another student with higher preference for that school?

Correct. You would have lost that seat either way.

[Anonymous]

my understanding (from a conversation with myschools) but I may have misunderstood, is that if you get into school #5 you will be waitlisted at schools #1-#4 and you will NOT be waitlisted at schools #6-#12


Yes you are correct. That is how it will work.

[Anonymous]

Anonymous wrote:my understanding (from a conversation with myschools) but I may have misunderstood, is that if you get into school #5 you will be waitlisted at schools #1-#4 and you will NOT be waitlisted at schools #6-#12


Yes you are correct. That is how it will work.

Yes. And this is how it worked last year as well when it was just a DCPS lottery (no charters).

This is why it's important to rank your true preferences. You may have only a snowball's chance in hell to get into, say, Inspired Teaching. But if you rank it #4 and you get into your #3 school, you are dead to Inspired Teaching. You don't exist in their system.

That's why Mundo Verde stated, "Rank us #1 to increase your chances." Not because listing it as #1 gives you a special consideration in the lottery.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:
Show me where it is clearly stated that random lottery number trumps student's ranking of the school and, where all else is equal except the student's rank of the school, a higher random lottery number trumps student's ranking of school?

It's not clearly stated because there isn't anything at all about rank in the FAQ. Let me ask this back: If rank were so important -- more important than lottery number -- why did they leave it out of the FAQ?

I have no idea why they left it out. I only know what the admissions people at the 2 schools I'm most interested in told me and the person representing the lottery at the fair I went to said. They clearly, unequivically said "Rank matters and a student with everything else the same but with who ranked the school lower would lose to a student who ranked it higher".

For me, that's all I need to know, and I'm acting on that regardless of what anonymous people on the internet say. But I'm interested in the sources people are using to assert so strongly that random lottery number trumps rank.

Very strange. When I asked the Schools DC people at the ward 5 school fair, they did not tell me that. They stressed that it was important to put your true first choice in the #1 slot and that your chances of getting in to each school were independent of each other or rank.

To be honest, I don't know if the MySchoolDC folks even know how it runs. They're hiring a nobel prize winning professor from Stanford to do it for them.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:
Show me where it is clearly stated that random lottery number trumps student's ranking of the school and, where all else is equal except the student's rank of the school, a higher random lottery number trumps student's ranking of school?

It's not clearly stated because there isn't anything at all about rank in the FAQ. Let me ask this back: If rank were so important -- more important than lottery number -- why did they leave it out of the FAQ?

I have no idea why they left it out. I only know what the admissions people at the 2 schools I'm most interested in told me and the person representing the lottery at the fair I went to said. They clearly, unequivically said "Rank matters and a student with everything else the same but with who ranked the school lower would lose to a student who ranked it higher".

For me, that's all I need to know, and I'm acting on that regardless of what anonymous people on the internet say. But I'm interested in the sources people are using to assert so strongly that random lottery number trumps rank.

Very strange. When I asked the Schools DC people at the ward 5 school fair, they did not tell me that. They stressed that it was important to put your true first choice in the #1 slot and that your chances of getting in to each school were independent of each other or rank.

To be honest, I don't know if the MySchoolDC folks even know how it runs. They're hiring a nobel prize winning professor from Stanford to do it for them.

DCUM folks at their finest

[Anonymous]

After reading through this thread I started to wonder...

What if you only have one school that you are interested in?
Should you add others just because or rank that school #1 and call it a day?

[Anonymous]

Anonymous wrote:After reading through this thread I started to wonder...

What if you only have one school that you are interested in?
Should you add others just because or rank that school #1 and call it a day?

What would be the point of adding schools that you would not consider actually enrolling in?

[Anonymous]

Anonymous wrote:After reading through this thread I started to wonder...

What if you only have one school that you are interested in?
Should you add others just because or rank that school #1 and call it a day?

There is no advantage to putting on schools that you wouldn't attend. Just put in the one you want.

[Anonymous]

Anonymous wrote:

Anonymous wrote:After reading through this thread I started to wonder...

What if you only have one school that you are interested in?
Should you add others just because or rank that school #1 and call it a day?

There is no advantage to putting on schools that you wouldn't attend. Just put in the one you want.

There is however a disadvantage to only applying to 1 school in this round. You may miss out on an opportunity at a school that can offer you something similar to what your only choice offers. I think this is a bigger deal if a) you aren't happy with your current school or b) you are applying for pre-school or pre-k.

If you have a backup plan (existing school, private school, homeschool) then having 1 selection isn't that big of a deal. If you don't have a backup, then I would spend the next few weeks researching schools and making as many choices as you can.

[Anonymous]

Your rankings matter. But lottery number matters more.

The algorithm assigns seats using the following factors, in order of priority:

1. Preferences
(varies by school; many have sibling preferences, DCPS has in-boundary preference for PK3 and PK4)

2. Lottery Number

3. Your Rankings

Lottery number trumps your ranking.

The reason MySchoolDC stresses that ranking matters is that it's unlike independent charter lotteries, where you could apply to many charter lotteries and then choose one among them later. This year, your rankings are used to assign you a single seat, so rankings matter -- you can't just list off a bunch of potential schools you might want.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:By law, sibs get preference. No ranking of algorithm will change that. So, if there are 10 open spots with 10 siblings to fill them, you will never get one of those 10 spots. Period.

So you're saying if I'm a Sibling at IT (my #12 choice) but get in at Mundo Verde (my #1) with an early choice, I will be able to keep my IT spot and bump someone from the IT spot? So I'm admitted to IT and high wait listed for MV?

No, if you get in at Mundo Verde you have given up your sibling preference at IT. If you get in at your #1 choice you are no longer on any wait lists.

If this is true then it really limits the potential for parent with two children to have both of their children attend the same school. For instance if this individual would like both of their children to attend MV, but only one gets is there no way that the parent can give up their spot at MV and send the child to IT? You must be able to give up your #1 and obtain through sibling preference a seat at a school you ranked lower. Could you not just apply after the lottery and move to the top of the IT waitlist based on sibling preference?

[Anonymous]

PP. I have been wondering about this also. We are thinking of changing schools but would only change if both kids got in to the new school (charter). If not we would enroll our younger one in PK3 at our in boundary school where our older one is.

Under the old system I could hold the IB spot to see if the charter spots came through - right through the summer.

Now I have to choose whether to place the charter above or below our IB school. If I place the charter above and the younger gets in but the older doesn't, I am cut out of our IB school until K and have kids at different schools. If I place the charter below I will likely get in to the IB school, so my younger won't end up on the wait list for the charter.

I don't feel like I am trying to game the system. Of course I can just go down the in boundary DCPS track. And it is a good school. But the middle school path is uncertain, and we would love to have language immersion.

Nostalgic for the chaos and flexibility of all the charters having their own lotteries.

[Anonymous]

Can any of our algorithm mavens tell us how the sibling preference is applied during the scenario above?

[Anonymous]

Anonymous wrote:PP. I have been wondering about this also. We are thinking of changing schools but would only change if both kids got in to the new school (charter). If not we would enroll our younger one in PK3 at our in boundary school where our older one is.

Under the old system I could hold the IB spot to see if the charter spots came through - right through the summer.

Now I have to choose whether to place the charter above or below our IB school. If I place the charter above and the younger gets in but the older doesn't, I am cut out of our IB school until K and have kids at different schools. If I place the charter below I will likely get in to the IB school, so my younger won't end up on the wait list for the charter.

I don't feel like I am trying to game the system. Of course I can just go down the in boundary DCPS track. And it is a good school. But the middle school path is uncertain, and we would love to have language immersion.

Nostalgic for the chaos and flexibility of all the charters having their own lotteries.

The families that did not get any spots in the lottery last year are not nostalgic for that at all, I assure you.

Even if you get "shut out" of your IB school, it is for 2 years at most. This is not a tragedy.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:By law, sibs get preference. No ranking of algorithm will change that. So, if there are 10 open spots with 10 siblings to fill them, you will never get one of those 10 spots. Period.

So you're saying if I'm a Sibling at IT (my #12 choice) but get in at Mundo Verde (my #1) with an early choice, I will be able to keep my IT spot and bump someone from the IT spot? So I'm admitted to IT and high wait listed for MV?

No, if you get in at Mundo Verde you have given up your sibling preference at IT. If you get in at your #1 choice you are no longer on any wait lists.

If this is true then it really limits the potential for parent with two children to have both of their children attend the same school. For instance if this individual would like both of their children to attend MV, but only one gets is there no way that the parent can give up their spot at MV and send the child to IT? You must be able to give up your #1 and obtain through sibling preference a seat at a school you ranked lower. Could you not just apply after the lottery and move to the top of the IT waitlist based on sibling preference?

You essentially forfeit your sibling preference when you rank another school higher than your sibling school.

If having both children attend the same school is important to you:
1. If one child is already at a school and the other one is doing the lottery, put your existing school #1 on the other kid's lottery application. If you don't put it #1, there is a risk that you'll get into a higher-ranked school and then have no chance of getting into your sibling school.
2. If you are doing the lottery for two kids, order the schools the same way for both kids. That way you're guaranteed that sibling preference for one will help the other if they don't both get into the same school. The sibling preference will be at the higher ranked of the two schools they get into.

Before the common lottery, if your two kids got into two different schools you would have sibling preference at both, now you only have it at the higher ranked. If you decide that the lower-ranked is a better choice you could enter the second chance lottery with sibling preference for the lower-ranked school.

If you rank your two kids differently you run the risk of forfeiting your sibling preference in the event that each gets into a school that is higher-ranked for him than the one his sibling got into.

This is the rare example of a case where it makes sense to rank strategically, rather than in strict order of your preference.