So I take the Skytrain to work every morning. The nature of the automated transit system and its frequency means that it’s basically impossible for any one train to arrive at the exact time every day. If even one person hold the door open for an extra second could mean a slightly altered schedule.
Where I catch the train going westbound, the trains come from two routes. Along the Expo line, the trains will come from the lovely community of Surrey, which is separated from the rest of Vancouver by water. In a way, Surrey is a lot like Manhattan in Escape From New York where New York has been turned into a maximum security prison island filled with degenerate criminals. Along with the fine citizens from Surrey, trains from there will also be considerably more crowded than from the other route.
The other trains come from Burnaby along the Millennium Line. These trains are way less crowded since people going westbound would have taken this route going the other way, instead of looping around to my station. These are the trains I look to take every morning because there are hardly any people on them.
Now I leave my apartment every morning at approximately the same time, with a variance of perhaps plus or minus five minutes. The trains at that time of day come with the frequency of anything between twenty seconds to perhaps three minutes. No matter what time I leave, it seems like nine times out of ten, the train I see pulling away from the station as I walk towards the platform is the empty one from Burnaby. My luck doesn’t run out there as invariably, the next train to arrive will be a super crowded one from Surrey.
I can’t seem to figure out why this seems to happen so frequently. Given the variability in the time I leave my apartment and the variability in the train arrival times, there should be more randomness in which type of train I see first.
Sometimes I try to slap luck in the face and let the first train go by without getting on. Almost invariably, the second train will be an almost empty one. Why? Why does this happen?