Reconstruction of instantaneous Muni speeds : 無料・フリー素材/写真
Reconstruction of instantaneous Muni speeds / Erica _ Fischer
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | It struck me on the way home from work that, even when all you know is the times that it took to move between points, not the speeds at the points themselves, it is still possible to calculate the average speed at each point. With a steady sampling rate and related points, if there are five times as many samples at point X as at point Y, traffic must move at a fifth the average speed at point X as it does at point Y.This map is not really necessary since the instantaneous Muni speeds at each point *are* known and don't have to be calculated, but this lets it serve as a sanity check for applying the algorithm to other data sets. It doesn't look exactly like the real instantaneous speeds, but for the most part it looks pretty reasonable, except at the Market Street subway stations, where there are weird artifacts from the extremely regular locations of the samples.I think it would be more surprising if they did look exactly the same, actually, because the calculated speeds should always be slower than the instantaneous speeds because corner-cutting shortens the distances.NextBus data, April 13-July 3, 2010 |
| 撮影日 | 2010-08-03 23:22:18 |
| 撮影者 | Erica _ Fischer |
| タグ | |
| 撮影地 | San Francisco, California, United States 地図 |