Found this from a blog comment about OSM.
"I suggest that you should invite a mapping professional into your group. Mapping is not a kiddy thing. It requires knowledge on Geometric Geodesy and GPS Systematic Errors. Without the required knowledge, doing mapping is just like wearing a blindfold blindly."
newbie: I want to contribute to OSM
OSM "expert": Welcome! I suggest you start reading ASPRS journals on Geodesy and GPS geometric corrections.
newbie: OH OK, bye.