UD_Norwegian

The Norwegian UD treebank is based on the Bokmål section of the Norwegian Dependency Treebank (NDT), which is a syntactic treebank of Norwegian. NDT was developed 2011-2014 at the National Library of Norway in collaboration with the Text Laboratory and the Department of Informatics at the University of Oslo. NDT has been automatically converted to the UD scheme by Lilja Øvrelid at the University of Oslo.

NDT contains around 300,000 tokens taken from a variety of genres. The treebank texts have been manually annotated for morphosyntactic information. The morphological annotation mainly follows mainly the Oslo-Bergen Tagger. The syntactic annotation follows, to a large extent, the Norwegian Reference Grammar, as well as a dependency annotation scheme formulated at the outset of the annotation project and iteratively refined throughout the construction of the treebank. For more information, see the references below.

DATA SPLITS

In creating the data splits, care has been taken to preserve contiguous texts in the different splits and also to keep a fair balance of genres in each of the splits. Petter Hohle created the splits for the Norwegian UD treebank. The splits were created by concatenating the following files (available with the distribution of NDT):

Training data (15696 sentences, 180 individual files):

ap001_0000 -- ap012_0002 (53 files)
bt001_0000 -- bt005_0001 (28 files)
db001a_0000 -- db013_0004 (42 files)
kk001_0000 -- kk005_0001 (10 files)
sp-bm001_0000 -- sp-bm001_0008 (9 files)
vg001_0000 -- vg002_0003 (8 files)
blogg-bm001_0000 -- blogg-bm003_0000 (9 files)
nou001_0000 -- nou004_0000 (10 files)
st001_0000 -- st005_0000 (11 files)

Development data (2410 sentences, 26 individual files):

ap012_0003 -- ap014_0002 (7 files)
bt005_0002 -- bt005_0005 (4 files)
db013_0005 -- db014_0002 (5 files)
kk006_00001 -- kk007_0000 (2 files)
sp-bm002_0000 -- sp-bm002_0001 (2 files)
vg002_0004 (1 file)
blogg-bm003_0001 -- blogg-bm003_0002 (2 files)
nou004_0001 (1 file)
st005_0001 -- st005_0002 (2 files)

Test data (1939 sentences, 26 individual files):

ap014_0003 -- ap015_0002 (7 files)
bt005_0006 -- bt006_0001 (4 files)
db014_0003 -- db014_0007 (5 files)
kk007_0001 -- kk008_0000 (2 files)
sp-bm003_0000 -- sp-bm003_0001 (2 files)
vg002_0005 (1 file)
blogg-bm003_0003 -- blogg-bm003_0004 (2 files)
nou004_0002 (1 file)
st005_0003 -- st005_0004 (2 files)

BASIC STATISTICS

Tree count: 20045

Word count: 311277

Token count: 311277

Dep. relations: 35 of which 2 language specific

POS tags: 17

Category=value feature pairs: 31

TOKENIZATION

White space always indicates a token boundary and punctuation constitute separate tokens, except:

numbers with periods, commas or colons, e.g. 1.3, 0,6, 10:13
abbreviations, e.g. f.eks., Carl J. Hambro
URLs, e.g. http://www.ifi.uio.no

The treebank does not contain multiword tokens.

MORPHOLOGY

The PoS-tags follow the universal tag set and does not add any language-specific PoS-tags. The morphological features follow the Oslo-Bergen Tagger scheme (Hagen et. al., 2000). PoS-tags and morphological features were converted automatically to the UD scheme.

SYNTAX

The syntactic annotation in the Norwegian UD treebank conforms to the UD guidelines, adding language-specific relations for relative clauses (acl:relcl) and verb particles (compound:prt). The annotation has been automatically converted to UD from the original dependency scheme described in Solberg et. al. (2014) and further described in the NDT guidelines (Kinn et. al.). The conversion has not been manually checked. There are a few known discrepancies from UD:

remnant elements in ellipsis are not attached to their correlate but rather to the main verb, since information about correct correlate is not present in the original annotation
no mwe analysis in the treebank. This is also information that is not present in the original data.

REFERENCES

Kristin Hagen, Janne Bondi Johannessen and Anders Nøklestad: "A Constraint-based Tagger for Norwegian". 2000. Proceedings of the 17th Scandinavian Conference in Linguistics.

Kari Kinn, Per Erik Solberg and Pål Kristian Eriksen. "NDT Guidelines for Morphological Annotation". National Library Tech Report.

Per Erik Solberg, Arne Skjærholt, Lilja Øvrelid, Kristin Hagen and Janne Bondi Johannessen. 2014."The Norwegian Dependency Treebank", Proceedings of LREC 2014, Reykjavik

Documentation status: partial Data source: automatic Data available since: UD v1.2 License: CC BY-NC-SA Genre: news blog nonfiction Contributors: Øvrelid, Lilja