Topic on User talk:Dcflyer/Structured Discussions Archive 1

I'd like to draw your attention to a feature of the Wikidata Query Service about which you might not have known: the "psn:" prefix. This is used with a property (the way "wdt:" might be) to indicate a quantity which has been normalized to a common unit based on the unit which accompanies the quantity in the original statement. In the case of distances, any quantity with a distance unit gets normalized to meters automatically, so as this query of places in Illinois with heights AMSL shows, even measurements in feet can be compared with meter measurements automatically if desired. It is thus my contention that separate statements for feet and meter measurements for elevation above sea level (P2044), as you've added to places in Washington, D.C. and the states near it, are unnecessary if both statements are cited to the same source.

Hi Mahir256,

Thank you for confirming what I have long suspected myself, that I was unnecessarily adding duplicate data points, via two statements containing equivalent values.

The motivating factor was that the Commons infobox template does not calculate and display converted units of imperial to metric, and vice versa; however, most (or all) of the infobox templates for the fr wiki automatically convert imperial units to the metric system, and if equivalent imperial and metric unit values are added to Wikidata like I had been doing, duplicate values are displayed in the those aforementioned infoboxes.

Recently, I have begun to add only a single value for elevation to items from GeoNames (Q830106) (metric unit), opposed to adding the two equivalent values from Geographic Names Information System (Q136736), which receive no updates. Going forward, I will only add a single value from a source that may have equivalent one(s), and I will remove the duplicate ones that I previously added to items.

Thank you!

Dcflyer