Hm. I wonder if there's a way to distinguish between "If this particular person gets hit by a bus, we're screwed" versus "If any of these n people get hit by a bus, we're screwed" (which is a lot worse).
How about looking at the number of people who must be removed in order to bring the bus factor down to 1? We can call it the "bus co-factor" :). With the bus factor we're picking the most critical people first, and removing the least number of them; with the bus co-factor we're picking the least critical people first, and removing the greatest number of them.
There's probably already some name and many theorems in graph theory for both of these ideas.
You can treat it like a reverse big-O notation. Your figure out the bus factor for each sub-task/system in your project (this is the risk factor) and then determine the priority of each sub-task/system. If a GUI is "easy" or low priority for your project, one GUI person doesn't mean your project has a bus factor of 1. But if networking is critical and you have one person that understands the novel telecon protocol stack you're using, that's a bus factor of 1.
gmaslov|12 years ago
There's probably already some name and many theorems in graph theory for both of these ideas.
Jtsummers|12 years ago