met AM o R phos ED , a graphical editor for A bstract M eaning R epresentation (2023)

Abstract: This paper presents a graphical editor for directed graphs, serialised in the PENMAN format, as used for annotations in Abstract Meaning Representation (AMR). The tool supports creating and modifying of AMR graphs and other directed graphs, adding and deletion of instances, edges and literals, renaming of concepts, relations and literals, setting a “top node” and validating the edited graph.

## introduction abstract meaning representation (amr) is a semantic representation language designed to formalise the meaning of sentences or a set of sentences @xcite 1 . its motivation is to annotate semantic information like named entities, coreferences, word senses, semantic relations etc. however, it does not annotate meaning of natural language at the same degree as more complex frameworks such as the discourse representation theory @xcite , as it does not mark number, semantic time, mode etc. even though amr has been explicitely devised for english and must not be considered as an interlingua, amr is increasingly used to annotate sentences in languages other than english @xcite @xcite . amr graphs are directed graphs which contain concepts, instances, literals and labelled edges between instances and literals. amr uses concepts from propbank @xcite where available (mainly verbal concepts), e.g., bear-02 in figure 1, propbank sense 2 for bear. instances are indicated by a following "/", e.g., p being an instance of the concept person. figure 1: amr graph for "queen elizabeth was born in 1926" in penman format (above) and graphical visualisation preceeding instance and "/" (c.f., "queen" and 1926 in the example in figure 1 ). amr data is available at the linguistic data consortium (ldc) for english 2 : the sentences of the test corpus of amr 2.0 were translated by human translators into four languages (ldc2020t07: amr 2.0, four translations of amr 2.0 test set into italian, spanish, german, chinese, 1371 sentences per language). foot_0 nearly all available annotated amr corpora use the penman graph serialisation format @xcite ; shown in figure 1 together with a graphical representation where instances and concepts are shown in one rectangle for better readability, the full visualisation of figure 1 would be the visualisation in figure 2 ). in addition to the penman serialisation, typical amr files contain some metadata too: the sentence itself, translations, a unique sentence identification, annotator identification, saving date, named entities, etc, e.g., figure 3 . since the amr graph is not anchored, i.e., there is no obvious link between words of the sentences and concepts, instances and relations in the graph, annotation of a corpus using a simple text editor is not possible. apart from the parentheses it would be very difficult to check manually whether the concepts are correctly chosen and the arguments (notably :arg0 to :arg9) defined for the chose concepts. the corpora mentioned in the amr project website have mostly been annotated and validated using the amr editor @xcite at https://amr.isi.edu/editor.html . since this tool is not available for download, and we wanted to annotate a specialised evaluation corpus, we started developping metamorphosed. our aim was a utility easy to use for annotators without any profound knowledge of semantic graphs, penman format or triplets and providing as much assistance to the annotators as possible. once you have clicked on load sentence , a view similar to the one in figure 4 appears. in addition to the sentence, the penman serialisation and the visualisation, the graphical user interface shows the propbank documentation of all the verbs found in the graph, and possible errors. ## conclusion and prospectives we presented a novel graph editor, suitable to create or modify and validate abstract meaning representation graphs in a visual mode. all modifications are git-version controlable. the code is actively maintained and available at https://github. com/orange-opensource/metamorphosed . meta-morphosed is currently used to annotate a test corpus containing 400 questions and turned out to be stable. apart from an interface to annotate amr coreferences, which has been implemented and is being tested (cf. figure 11) we plan several future developments, notably a multi-user system, where multiple users can annotate the same file with integrated calculation of annotator agreement. another improvement could be an automatic search of similar sentences in a reference corpus (such as amr 3.0) to ensure that similar constructions and sentences are annotated homogenously. other ideas include providing a way to integrate plugins which could run queries to external systems to facilitate the annotation as much as possible. we will consider comments and issues posted by users to decide which feature is the most urgent to be implemented first.