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After reading your Question, and the various Answers, I got interested in this problem. After doing a bit of reading on Map-matching algorithms, I have understood the following:
- To Match the gps Location to road, you need the actual road data in vector format
- It will help if you have different weights for different roads. So the chances of a point matching with a highway will be higher, then with matching a side line.
- You need to take the history, and speed of the gps reading. For example if the the gps point has been matching the side lane for a long time, you should take that into account, and not match it directly to highway. -The actual matching is done using a variety of statistical techniques.
For Further reading, I suggest the following:
