This repository contains code for our paper.

Yosuke Mikami, Daiki Matsuoka, and Hitomi Yanaka. 2025. Implementing a logical inference system for japanese comparatives. In Proceedings of the 5th Natural Logic Meets Machine Learning Workshop. Association for Computational Linguistics.

• Python 3.7+
• Vampire 4.9
• Tsurgeon 4.2.0

Our system uses the scripts available from ccg2lambda. You need to install Python (3.7+), nltk, lxml, simplejson, and pyyaml. If you already have installed python3 and pip, you can install them as follows:

$ pip install nltk lxml simplejson pyyaml

See also installation of ccg2lambda.

The system also uses pykakasi, so install it.

$ pip install pykakasi

To run the system, you have to clone this repository first.

• For HTTPS

  $ git clone https://github.com/ynklab/ccg-jcomp.git

• For SSH

  $ git clone git@github.com:ynklab/ccg-jcomp.git

• To install Vampire, run the following command:

  $ cd ccg-jcomp
  $ ./tools/install_vampire.sh

• To install Tsurgeon, run the following command:

  $ cd ccg-jcomp
  $ ./tools/install_tsurgeon.sh

If Permission denied error occurs, change the permission using chmod command.

These commands download Vampire 4.9 to ccg-jcomp/vampire-4.9casc2024 and Tsurgeon 4.2.0 to ccg-jcomp/stanford-tregex-2020-11-17, respectively.

The location of each tool is written in scripts/vampire_dir.txt and scripts/tsurgeon_dir.txt, respectively. You can change the location by editing them.

This system uses depccg as a CCG parser.

$ pip install cython numpy depccg

See also depccg.

Let's try the following inference example. The first sentence is a premise which means that Taro is more cheerful than Hanako and presupposes that Hanako is cheerful. The second one is a hypothesis which means that Hanako is cheerful. Thus, the gold answer is yes (entailment).

Save this as ccg-jcomp/test.txt.

太郎は花子以上に明るい。
花子は明るい。

You can run the system by the following command.

$ ./scripts/rte.sh test.txt scripts/semantic_templates_ja_event_degree_multi.yaml

The output will be in results directory.

$ ./scripts/eval_jsem.sh <semantic_template>

This may take some time.

Yosuke Mikami, Daiki Matsuoka, and Hitomi Yanaka. 2025. Implementing a logical inference system for japanese comparatives. In Proceedings of the 5th Natural Logic Meets Machine Learning Workshop. Association for Computational Linguistics.

@inproceedings{Mikami-Matsuoka-Yanaka-2025,
    title = "Implementing a Logical Inference System for Japanese Comparatives",
    author = "Mikami, Yosuke  and
      Matsuoka, Daiki  and
      Yanaka, Hitomi",
    editor = "Abzianidze, Lasha  and
      de Paiva, Valeria",
    booktitle = "Proceedings of the 5th Natural Logic Meets Machine Learning Workshop",
    month = aug,
    year = "2025",
    publisher = "Association for Computational Linguistics"
}