Relation pm#probability_relation__probabilityrelation (formula,?)
  subtype:  probability_fn  conditional_probability  increases_likelihood  decreases_likelihood  independent_probability
  type:  probability_relation_type  the class of relations that permit assessment of the probability of an event or situation
  supertype:  relation_from_description (description,*)
     supertype:  relation_from_description_content/medium/container (description_content/medium/container,*)
        supertype:  relation_from/to_thing_of_common_kind (*)  this type permits to categorize relations according to their signatures and hence offers (i) a concise way to set essential exclusion relations, and (ii) a systematic and easy-to-follow categorization
           >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type