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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.

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