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I could not find any used solution for marking up information as hypothetical so I did it in my own way.

For dates OHM seams to use start_date/end_date(that’s at least what I have been seeing).

So when I decided on how I would mark up hypothetical information I wanted to be flexible. I started with ohm:hypothetical, then follows the tag/key that’s hypothetical. for example a hypothetical start_date would look like: ohm:hypothetical:start_date=yes this would also allow the value to be no for none hypothetical information.

The reason not to use ohm:hypothetical=<tag-name>" is that then you can’t have more then one ohm:hypothetical tag(OSM does not allow duplicate keys).

Example uses:

• ohm:hypothetical:name=yes
• ohm:hypothetical:start_date=yes
• ohm:hypothetical:end_date=no
• ohm:hypothetical:landuse=yes
• …

For marking up a hypothetical location I can see two approaches one is to just have ohm:hypothetical:ohm:location=yes another is go with ohm:hypothetical=yes.

Another approach to the problem would be to just append the hypothetical key with :hypothetical or :verifiable,

If it does exist a common solution I can replace my one, but I could not find one…

Anyone else that have been marking up any data as hypothetical? How did you do this?

Feedback on this?

The tags start_date/end_date should they be ohm:start_date/ohm:end_date? They are OHM specific as far as I know.

Hi! I wonder if I’m on the right track? I’ve created boundaries for parishes in Stockholm county. The ambition has been to capture all changes. Every change means that a new parish is created. So far their names are separated by the addition of years to their names. Waiting for the time slider the boundaries are all piled on one another.

Who wants to work on a “getting started” guide for OHM? I’d love to collaborate and learn more about the platform.

So, I’m not sure how many people are on this website. I just made this account today. I was going to start working on a historical map of the Chicago “L” Train system based on year. Are we allowed to contribute to the building of the time/date slider?

OpenHistoricalMap.org is working again… well the website only at least