henry_familysize_by_maryear.rq

#+ summary: family size by marriage year
#+ tags:
#+    - henry
#+    - family size

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX henry: <http://data.socialhistory.org/ns/resource/henry/>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>

SELECT (AVG(?n_child) AS ?familysize) ?decade_marriage 
FROM <http://data.socialhistory.org/ns/resource/henry_test>
WHERE{
    SELECT (COUNT(?child) AS ?n_child) ?parent ?decade_marriage
    WHERE {
        ?parent henry:CHILD ?child.
        ?parent henry:AN_MA ?year_marriage.
        BIND(FLOOR(?year_marriage / 10) * 10 AS ?decade_marriage) .
    }
}
ORDER BY ASC(?decade_marriage)