Do homeless people have a single canonical name that they will use consistently?<p>Is it fair to request that they structure their day around a hashing algorithm that they don't understand?<p>There's an arbitrary kind of "command" oriented aspect to this that I'm not crazy about. Sort of a "the algorithm says that you go here at time X" element that is inscrutable and will no doubt inspire a lot of theories about how it's rigged ("Hispanic names always get to go in the morning, did you notice?").<p>I would suggest colored tokens that are good for certain timeslots: Red might mean "Monday at 9, Tuesday at 10, ...". I don't know if they are persistent or good for one use or both. The tokens can be recollected so you know how many are circulating for a given time/place and can avoid oversubscription.<p>These could be handed out at random and traded among the clients so they can put together a schedule that suits them. This removes the "arbitrary computer says so" kind of element of the hashing scheme.
If I had to quickly assign numbers to buckets using a hash table would be obvious but I would never have thought of using the same ideas for assigning people to lines.<p>This reminds me of a joke I once heard - if you want the cold soda you need to get to the one in the back of the fridge. That's what you get for implementing the fridge as a stack.<p>Data structures are all around us, we just need to recognize it.
It's an interesting idea but I don't think the ID problem is as trivial as the proposal makes it. For example,<p><a href="http://www.nlchp.org/content/pubs/Photo%20ID%20Barriers1.pdf" rel="nofollow">http://www.nlchp.org/content/pubs/Photo%20ID%20Barriers1.pdf</a>