Searching for Annotations

Annotations may be searched for using an annotation name and value. The names of the annotations vary from corpus to corpus, though many corpora contain part-of-speech and lemma annotations with the names pos and lemma respectively (annotation names are case sensitive). For example, to search for all forms of the verb be in the GUM corpus, simply select the GUM corpus and enter:

lemma="be"

Negative searches are also possible using != instead of =. For negated tokens (word forms) use the reserved attribute tok. For example:

lemma!="be"

or:

tok!="be" 

Metadata attributes can also be negated:

lemma="be" @* type!="interview"

To only find finite forms of a verb in GUM, use the part-of-speech (pos) annotation concurrently with lemma, and specify that both the lemma and pos should apply to the same element. For example for inflected forms of the verb give:

lemma="give" & pos=/VV.+/ & #1 _=_ #2

OR (using a shortcut):

lemma="give" _=_ pos=/VV.+/

The regular expression /VV.+/ means a part of speach that begins with VV (verb), but has additional characters (.+), such as for past tense (VVD) or gerund (VVG). The expression #1 _=_ #2 uses the span identity operator to specify that the first annotation and the second annotation apply to exactly the same position in the corpus.

Annotations can also apply to longer spans than a single token: for example, in GUM, the annotation entity signifies the entity type of a discourse referent. This annotation can also apply to phrases longer than one token. The following query finds spans containing a discourse referent who is a person:

entity="person"

If the corpus contains more than one annotation type named entity, a namespace may be added to disambiguate these annotations (for example, the entity annotation in the GUM corpus has the namespace ref:, so we can search for ref:entity="person"). The namespace may always be dropped, but if there are multiple annotations with the same name but different namespaces, dropping the namespace will find all of those annotations. If you drop the value of the annotation, you can also search for any corpus positions that have that annotation, without constraining the value. For example, the following query finds all annotated entities in the GUM corpus, whether or not they are a person:

entity

In order to view the span of tokens to which the entity annotation applies, enter the query and click on "Search", then open the referents layer to view the grid containing the span.

Further operators can test the relationships between potentially overlapping annotations in spans. For example, the operator _i_ examines whether one annotation fully contains the span of another annotation (the i stands for 'includes'):

head & infstat="new" & #1 _i_ #2

OR (using a shortcut):

head _i_ infstat="new"

This query finds information structurally new discourse referents (infstat="new") contained within headings (head).