This is a Japanese text corpus that consists of lead three sentences of web documents with various linguistic annotations. By collecting lead three sentences of web documents, this corpus contains documents with various genres and styles, such as news articles, encyclopedic articles, blogs and commercial pages. It comprises approximately 5,000 documents, which correspond to 15,000 sentences.

The linguistic annotations consist of annotations of morphology, named entities, dependencies, predicate-argument structures including zero anaphora, coreferences, and discourse. All the annotations except discourse annotations were given by manually modifying automatic analyses of the morphological analyzer JUMAN and the dependency, case structure and anaphora analyzer KNP. The discourse annotations were given by two types of annotators; experts and crowd workers.

This corpus consists of linguistically annotated Web documents that have been made publicly available on the Web at some time. The corpus is released for the purpose of contributing to the research of natural language processing.

Since the collected documents are fragmentary, i.e., only the lead three sentences of each Web document, we have not obtained permission from copyright owners of the Web documents and do not provide source information such as URL. If copyright owners of Web documents request the addition of source information or deletion of these documents, we will update the corpus and newly release it. In this case, please delete the downloaded old version and replace it with the new version.

The annotation guidelines for this corpus are written in the manuals found in the "doc" directory. The guidelines for morphology and dependencies are described in syn_guideline.pdf, those for predicate-argument structures and coreferences are described in rel_guideline.pdf, and those for discourse relations are described in disc_guideline.pdf. The guidelines for named entities are available on the IREX website (http://nlp.cs.nyu.edu/irex/).

• knp/: the corpus annotated with morphology, named entities, dependencies, predicate-argument structures, and coreferences
• disc/: the corpus annotated with discourse relations
• org/: the raw corpus
• doc/: annotation guidelines
• id/: document id files providing train/test split

Annotations of this corpus are given in the following format.

# S-ID:w201106-0000010001-1
* 2D
  3D
太郎 たろう 太郎 名詞 6 人名 5 * 0 * 0
は は は 助詞 9 副助詞 2 * 0 * 0
* 2D
  2D
京都 きょうと 京都 名詞 6 地名 4 * 0 * 0
  3D <NE:ORGANIZATION:京都大学>
大学 だいがく 大学 名詞 6 普通名詞 1 * 0 * 0
に に に 助詞 9 格助詞 1 * 0 * 0
* -1D
  -1D <rel type="ガ" target="太郎" sid="w201106-0000010001-1" id="0"/><rel type="ニ" target="大学" sid="w201106-0000010001-1" id="2"/>
行った いった 行く 動詞 2 * 0 子音動詞カ行促音便形 3 タ形 10
EOS

The first line represents the ID of this sentence. In the subsequent lines, the lines starting with "*" denote "bunsetsu," the lines starting with " " denote basic phrases, and the other lines denote morphemes.

The line of morphemes is the same as the output of the morphological analyzers, JUMAN and Juman . This information includes surface string, reading, lemma, part of speech (POS), fine-grained POS, conjugate type, and conjugate form. "*" means that its field is not available. Note that this format is slightly different from KWDLC 1.0, which adopted the same format as Kyoto University Text Corpus 4.0.

The line starting with "*" represents "bunsetsu," which is a conventional unit for dependency in Japanese. "Bunsetsu" consists of one or more content words and zero or more function words. In this line, the first numeral means the ID of its depending head. The subsequent alphabet denotes the type of dependency relation, i.e., "D" (normal dependency), "P" (coordination dependency), "I" (incomplete coordination dependency), and "A" (appositive dependency).

The line starting with " " represents a basic phrase, which is a unit to which various relations are annotated. A basic phrase consists of one content word and zero or more function words. Therefore, it is equivalent to a bunsetsu or a part of a bunsetsu. In this line, the first numeral means the ID of its depending head. The subsequent alphabet is defined in the same way as bunsetsu. The remaining part of this line includes the annotations of named entity and various relations.

Annotations of named entity are given in <NE> tags. <NE> has the following four attributes: type, target, possibility, and optional_type, which mean the class of a named entity, the string of a named entity, possible classes for an OPTIONAL named entity, and a type for an OPTIONAL named entity, respectively. The details of these attributes are described in the IREX annotation guidelines.

Annotations of various relations are given in <rel> tags. <rel> has the following four attributes: type, target, sid, and id, which mean the name of a relation, the string of the counterpart, the sentence ID of the counterpart, and the basic phrase ID of the counterpart, respectively. If a basic phrase has multiple tags of the same type, a "mode" attribute is also assigned, which has one of "AND," "OR," and "？." The details of these attributes are described in the annotation guidelines (rel_guideline.pdf).

In this corpus, a clause pair is given a discourse type and its votes as follows.

# A-ID:w201106-0001998536
1 今日とある企業のトップの話を聞くことが出来た。
2 経営者として何事も全てビジネスチャンスに変えるマインドが大切だと感じた。
3 生きていく上で追い風もあれば、
4 逆風もある。
1-2 談話関係なし:5  原因・理由:4  条件:1
3-4 原因・理由:3  談話関係なし:2  逆接:2  対比:2  目的:1

The first line represents the ID of this document, the subsequent block denotes clause IDs and clauses, and the last block denotes discourse relations for clause pairs and their voting results. These discourse relations and voting results are the results of the second stage of crowdsourcing. Each line is the list of a discourse relation and its votes in order of votes. For the discourse relation annotated by experts, the discourse direction is annotated; if it is reverse order, "(逆方向)" is added to the discourse relation. The details of annotation methods and discourse relations are described in [Kawahara et al., 2014] and the annotation guidelines (disc_guideline.pdf).

• Masatsugu Hangyo, Daisuke Kawahara and Sadao Kurohashi. Building a Diverse Document Leads Corpus Annotated with Semantic Relations, In Proceedings of the 26th Pacific Asia Conference on Language Information and Computing, pp.535-544, 2012. http://www.aclweb.org/anthology/Y/Y12/Y12-1058.pdf
• 萩行正嗣, 河原大輔, 黒橋禎夫. 多様な文書の書き始めに対する意味関係タグ付きコーパスの構築とその分析, 自然言語処理, Vol.21, No.2, pp.213-248, 2014. https://doi.org/10.5715/jnlp.21.213
• Daisuke Kawahara, Yuichiro Machida, Tomohide Shibata, Sadao Kurohashi, Hayato Kobayashi and Manabu Sassano. Rapid Development of a Corpus with Discourse Annotations using Two-stage Crowdsourcing, In Proceedings of the 25th International Conference on Computational Linguistics, pp.269-278, 2014. http://www.aclweb.org/anthology/C/C14/C14-1027.pdf
• 岸本裕大, 村脇有吾, 河原大輔, 黒橋禎夫. 日本語談話関係解析：タスク設計・談話標識の自動認識・ コーパスアノテーション, 自然言語処理, Vol.27, No.4, pp.889-931, 2020. https://doi.org/10.5715/jnlp.27.889

The creation of this corpus was supported by JSPS KAKENHI Grant Number 24300053 and JST CREST "Advanced Core Technologies for Big Data Integration." The discourse annotations were acquired by crowdsourcing under the support of Yahoo! Japan Corporation. We deeply appreciate their support.

If you have any questions or problems with this corpus, please send an email to nl-resource at nlp.ist.i.kyoto-u.ac.jp. If you have a request to add source information or to delete a document in the corpus, please send an email to this mail address.