In Patel et al., Using Semantic and Structural Properties of the Unified Medical Language System to Discover Potential Terminological Relationships, JAMIA 2009, Vol 16 Number 3, May/June 2009, there was a typographical error where a lower case Greek epsilon was omitted from the text on page 349 under the “Scale Analysis” heading.
The text reads
“where degree(C1) = |{C2 ਲ UMLS Concepts: C1 and C2 have a relationship in MRREL}| and k is an arbitrary cut off parameter.”
It should read
“where degree(C1) = |{C2 ɛ UMLS Concepts: C1 and C2 have a relationship in MRREL}| and k is an arbitrary cut off parameter.”
The ɛ in this text indicates that C2 is an element of the set “UMLS CONCEPTS.”