Talk:Key:easy overtaking

Verifiability?

How should a mapper confirm if this tag is applied correctly? See Verifiability. Is this tag a subjective review of a certain stretch of road by a particular mapper, or is there some objectively observable characteristic which can be used to determine when it should or should not be added? --Jeisenbe (talk) 03:56, 13 September 2019 (UTC)

All of the "indications" listed on the page should be verifiable, even if there could be exceptional places where they're not sufficient, or where some of them aren't necessary. Verifiability doesn't mean it should have a simple sign one can look at before adding a tag, but that the next mapper can look at and discuss the evidence for adding the tag. Alv (talk) 04:26, 13 September 2019 (UTC)

Re: "Many places where overtaking is allowed are not considered as "easy" - in the USA places where overtaking is allowed are shown by paint marking, signs or both. These are fairly easy to see and can show when to map overtaking=yes/no, but the list of "easy" overtaking criteria on this page appears to be impossible for an ordinary person to use:

"The driver must be able to see the road at least twice as far as he or she were to travel when driving at the maximum legal and possible speed and when overtaking a full length trailer (or other longest allowed vehicle) driving 10 km/h under the speed limit; remember that in addition to the length of the vehicle being overtaken there needs to be at least some 5 meters gap at both ends when changing the lane. Add to that time spent on the wrong lane, and a 2-5 seconds safety margin

How is a mapper with GPS device and aerial imagery supposed to determine this when visiting a place? I suspect that mappers using this tag are not following such complex instructions, but using it in a way that means "I think this is an easy place to overtake", so it's like a review "this restaurant has excellent food" which might not be observed by another person with different life experience and preferences. Recall that a tag is "verifiable if and only if independent users observing the same feature would make the same observation every time." --Jeisenbe (talk) 05:07, 13 September 2019 (UTC)

If mappers make mistakes, the next one can correct it. The independent observers would make the same observation every time, when they follow the instructions; verifiability doesn't mean it must be super easy to observe. Somebody better use a "i_thought_it_was_easy_to_overtake" tag, if that's what they observed - not that I would suggest they should do, because maybe the next mapper wouldn't, as in your made up example of a excellent food. Most likely to get accurate results, the mapper needs to compare video to aerial imagery and do some math. Alv (talk) 05:49, 13 September 2019 (UTC)

Re: "to get accurate results, the mapper needs to compare video to aerial imagery and do some math" - have you done this yourself every time that you have added this tag? That sounds impractical: it's not something that a mapper can do. See some of the examples at Verifiability#Statistical_properties - the number of "vehicles per hour" on a road is not practically verifiable, because a mapper would have to sit by the street for hours and count each vehicle. It's theoretical possible, but will not actually be done in practice. This is the same problem with the very long and complex description of this tag. Tags in Openstreetmap should be able to be confirmed as correct or incorrect when a local mapper visits the place in person: "It is not sufficient if something is verifiable in theory. It must be practically verifiable in everyday mapping." --Jeisenbe (talk) 06:52, 13 September 2019 (UTC)