Exploring semantic groups through visual approaches

Abstract

Objectives. We investigate several visual approaches for exploring semantic groups, a grouping of semantic types from the Unified Medical Language System (UMLS) semantic network. We are particularly interested in the semantic coherence of the groups, and we use the semantic relationships as important indicators of that coherence. Methods. First, we create a radial representation of the number of relationships among the groups, generating a profile for each semantic group. Second, we show that, in our partition, the relationships are organized around a limited number of pivot groups and that partitions created at random do not exhibit this property. Finally, we use correspondence analysis to visualize groupings resulting from the association between semantic types and the relationships. Results. The three approaches provide different views on the semantic groups and help detect potential inconsistencies. They make outliers immediately apparent, and, thus, serve as a tool for auditing and validating both the semantic network and the semantic groups.

Fig. 1

Semantic types trees for Activity and Event, with semantic groups (the tree structure is represented by the indentations).

Fig. 2

Radial diagrams for semantic groups Anatomy and Physiology.

Fig. 3

Radial diagram for semantic group Disorders.

Fig. 4

Subsets of edges for the relationship treats (each style of line corresponds to a subset of edges: plain for DISO, dotted for LIVB).

Fig. 5

Subsets of edges for the relationship location_of (each style of line corresponds to a subset of edges, e.g., grey and dotted for ORGA).

Fig. 6

Correspondence analysis diagram.