Pointing relations are used to express an arbitrary directed relationship between two elements (terminals or non-terminals) without implying dominance or coverage inheritance. For instance, in the pcc2 demo corpus, elements in the mmax: namespace may point to each other to express coreference or anaphoric relations. The following query searches for two np_form annotations, which specify for example whether a nominal phrase is pronominal, definite or indefinite.
mmax:np_form="pper" &Using the pointing relation operator -> with the type anaphor_antecedent, the first np_form, which should be a personal pronoun (pper), is said to be the anaphor to its antecedent, the second np_form, which is definite (defnp). To see a visualization of the coreference relations, open the mmax annotation level in the example corpus. In the image below, one of the matches for the above query is highlighted in red (die Seeburger und einige Groß-Glienicker ... sie ‘the Seeburgers and some Groß-Glienickers... they’). Other discourse referents in the text (marked with an underline) may be clicked on, causing coreferential chains containing them to be highlighted as well. Note that discourse referents may overlap, leading to multiple underlines: Die Seeburger ‘the Seeburgers’ is a shorter discourse referent overlapping with the larger one (‘the Seeburgers and some Groß-Glienickers’), and each referent has its own underline. Annotations of the coreference edges of each relation can be viewed by hovering of the appropriate underline.
Another way to use pointing relations is found in syntactic dependency trees. The queries in this case can use both pointing relation types and annotations, as in the following query:
pos="VVFIN" & tok & #1 ->dep[func="obja"] #2This query searches for a finite verb (with the part-of-speech VVFIN) and a token, with a pointing relation of the type ‘dep’ (for dependency) between the two, annotated with ‘func="obja"’ (the function Object, Accusative). The result can be viewed with the dependency arch visualizer, which shows the verb gibt ‘gives’ and its object Wunder ‘miracles’.