Dear list,
Hi,
I am wondering whether the following SPARQL query can be more optimized. It
calculates a summation of (2P(E)P(E|C)-P(E|C)^2), given concept C, such as "
http://dbpedia.org/class/yago/PhysicalEntity100001930"; shown below.
I know this is not exactly related to this list, but still want to seek
some helps here, sorry for this.
select (sum(?subTotal) as ?sum) where {
{select ((2*count(?inst)*?countec/?countc -
?countec/?countc*?countec/?countc) as ?subTotal)
where {
?inst <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <
http://dbpedia.org/class/yago/PhysicalEntity100001930>.
{select (count(?inst1) as ?countc) ?c ?countec
where{
?inst1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> ?c.
{select (count(?inst) as ?countec) ?c
WHERE{
?inst <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <
http://dbpedia.org/class/yago/PhysicalEntity100001930>;
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type> ?c.
filter (str(?c)!= "http://dbpedia.org/class/yago/PhysicalEntity100001930";)
} GROUP BY ?c } }
GROUP BY ?c ?countec }} group by ?countc ?countec }}
thanks,
June
