OpenStreetMap
Working with JOSM I recently stumbled often on orphaned nodes scattered in the Data Layers (which I downloaded from OSM). These are often located near or on streets (which sometimes are mapped) and have no tags.
Example: http://enjoys.it/stuff/OSM_orphandots.png
What should I do with those, delete them?
Discussion
Comment from NicRoets on 20 February 2008 at 18:21
My guess is that someone converted tracks to nodes instead of either (a) converting them to ways or (b) using them to improve the accuracy of existing ways. JOSM allows you to see which user edited them last (provided they are 'public') and if they have any tags. You can also try to download the GPS data from that area and see if it lines up.
IMHO, nodes without tags that are not part of ways contains to information and should be deleted. This will help prevent that annoying situation where 2 nodes are close to each other and JOSM pick the wrong one.
Comment from Brian Schimmel on 20 February 2008 at 23:15
The screenshot looks as if those nodes would form a proper way if they were on a way. A friend of mine had the same issue with some coastline he mapped: There was a proper way, then someone (or something?) came along, removed the way but leaved the nodes.
If this is a major phenomenon in your area, and if it looks like there was some data that is now lost, it should be possible for some admin-like user to revert the old data.
I guess this is a rather complex procedure and is inappropriete if it concerns only one or two highways.
Comment from HannesHH on 22 February 2008 at 14:09
Thanks for your answers.
The area is/was very low on content. And since I am mapping/fixing most of it anyways I will simply delete those and create new "proper" nodes. It's not many, maybe 2% of all nodes in this area. Plus they are not "good quality" anyways.