I recently saw a Simpsons episode where Bart and Lisa go on a field trip. The teacher pairs up students to use the buddy system to make sure know one gets left behind. Bart and Lisa are buddies and they both get lost. On the bus to return to school, the teacher asks, “is anyone missing their buddy?” Since Bart and Lisa are both missing, they get left behind, and a big deal is made later about the failure of the buddy system, previously believed to be infallible.
So that got me wondering, what modifications would have to be made to the buddy system to make sure no subset of the members got left behind? What’s the minimum number of buddies each member would have to have for a given population size? Some kind of hypercube of connections?
I think the solution is simpler than that: a chain system. That is, line everybody up and each person is responsible to remember the person before them and the person after them. Everyone except the first and last members has two buddies each. That gives N-1 links with mostly 2 links per member compared to the buddy system, which has N/2 links for exactly 1 buddy per member. Plus, the chain system works for odd numbers of members, unlike the buddy system.
but what if the last two students in the chain go missing? The third from last will report the second from last as missing, but the poor last kid will be in trouble. Well, I guess, if they find the second to last kid, he can then report that the last kid is missing. But he may be too shaken to remember under the circumstances. And, what if they find the last kid first, who wasn’t even reported as missing. That could really confuse things.
Would it help if they lined up in a circle? I guess not, because if three in a row go missing, the middle guy won’t be reported, which is also a problem in the basic chain.
Maybe they could just do a roll call to quickly isolate the exact identities of the missing?
I think I may regret hitting submit on this one.
I guess as long as you keep lining them up in a chain as kids are found you are safe. I still would go with the circle, so the first and last are not dependent on one set of eyes.
or are you advocating that the kids stay in the chain, like you see with first graders walking through the city?
The point of any such system is to provide a quick check so the teacher can decide if it’s necessary to call roll. So as long as you identify that somebody is missing, it will trigger the roll call.
However, lining up is a bit of trouble and having each student remember two buddies is probably too much to depend on…