ChiefKiasu:pirate:[quote=\"ChiefKiasu\"]I believe the context is something like this.
Say the number of vacancies is 50
The number of parents applying with 1 child is 49.
One parent has 1 set of twins.
So total number of places needed is 51
But in a ballot situation, the parent with the twin will choose to submit only 1 ballot with both names in it.
So the total number of balls in the thingy will be 50, not 51.
So whether we ballot or not, every one of the 50 families will get a place.
So no need to ballot lor.
No, it doesn't work like this.
There are 50 balls and 50 vacancies, but 51 places needed.
If the first ball that rolled out belonged to the twins, there would be 48 places left and 49 balls left in the cage, ie. 1 kid will be balloted out.
Likewise, if the twins' ball was the 2nd ball to fall out, or the 3rd... and so on and so forth.
Only if the twins' ball was the last to fall out would 51 places be taken up at the ballot.
The chance that the twins' ball would be the last to fall out is actually very slim.
Cannot anyhow take shortcut, otherwise it is not fair to the people in the next phase.
Hmmm... I believe you are right! Good point. This is deserving of further clarification with MOE.[/quote]Thanks for sharing.
The basis for not conducting the ballot in MGS and ACJS it that if balloting were to take place it would be unfair to the parents of singletons as the twins would be guaranteed a place regardless of whether the twins are drawn earlier or last which is not the case for singletons.
So in the case of ACJS, there were 47 vacancies, 48 boys (including twins). As twins would be assigned 1 common ballot number, there would be 47 numbers.
If twins were drawn say from the 1st to the 46th try, balloting would have to stop as all 47 places would be filled. If the twins were drawn last, there would be 48 places.
In short the twins are guaranteed a place whether they are drawn earlier or last, while singletons are guaranteed a place if and only if the twins are drawn last (which is extremely remote).
Balloting cannot proceed because it would then be an unlevel playing field.
The MGS and ACJS scenarios are extremely rare, where vacancies were exceeded by just 1 slot because of the twins.
MOE made the right call not to have balloting.
Cheers.