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sparqlwikidata

Obtain the average number of distinct values for each of the properties

I am trying with SPARQL querying to do this:

For each of the properties, obtain the average number of distinct values that they take for the instances (e.g., what is the average number of occupations for a Formula 1 Driver, what is the average number of teams that they have participated in, etc.)

Solution

  • You would need a query like:

    SELECT ?p (AVG(?ct) AS ?avg)
WHERE {
   SELECT ?s ?p (COUNT(DISTINCT ?o) AS ?ct) 
   WHERE {
      ?s ?p ?o .
      #more restrictions...
          }
   GROUP BY ?s ?p }
GROUP BY ?p

    Notice that this approach ignores instances where the count is 0, i.e. a F1 driver with no profession.

    Also, the query is likely to time out unless you add some more restrictions to reduce the size of the matched data.