On 28 November 2015 at 19:17, Ed Erhart the.ed17@gmail.com wrote:
On the very specific point of knowledge and how it's not always possible to boil it down to a single quantifiable value, I couldn't agree more. Thank you, Andreas, for the detailed anecdote displaying that problem, and I'll be happy to provide more if needed.
Does Wikidata have a way of marking data entries as estimates, or at least dates as circa (not just unknown)?
Yes https://www.wikidata.org/wiki/Property:P1317 however a quick comparison between the English Wikipedia and wikidata suggests it isn't used very much.
Of course there are a bunch of other issues. It gives dates for Egyptian Pharaohs without saying what chronology it is using. It keeps claiming dates are Gregorian without showing any conversion has actually taken place (wikipedians tend to be pretty poor when it comes to such conversions since they require a fair bit of background knowledge. For example depending on the year and writer the year in England can start on the 1st of January, 25th March or the first day of advent).
Wikidata doesn't do very well on carbon dating either. If we look at Ötzi https://www.wikidata.org/wiki/Q171291
We again get dates with no indication of the calibration used. Really this would be better handled using the uncalibrated C14 numbers (4550 ± 27BP http://digitalcommons.library.arizona.edu/objectviewer?o=http%3A%2F%2Fradioc... ) and then adding enough information for the correct calibration curve to be selected (Northern hemisphere land based which at the moment probably means INTCAL13)