About: http://webisa.webdatacommons.org/299319103

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	A covariate is fixed if its values can not change with time, e.g. sex or race.
http://www.w3.org/ns/prov#wasQuotedFrom	statsdirect.com