Cookpad Parsed Corpus: Linguistic Annotations of J apanese Recipes (2020)

Abstract: It has become increasingly common for people to share cooking recipes on the Internet. Along with the increase in the number of shared recipes, there have been corresponding increases in recipe-related studies and datasets. However, there are still few datasets that provide linguistic annotations for the recipe-related studies even though such annotations should form the basis of the studies. This paper introduces a novel recipe-related dataset, named Cookpad Parsed Corpus, which contains linguistic annotations for Japanese recipes. We randomly extracted 500 recipes from the largest recipe-related dataset, the Cookpad Recipe Dataset, and annotated 4; 738 sentences in the recipes with morphemes, named entities, and dependency relations. This paper also reports benchmark results on our corpus for Japanese morphological analysis, named entity recognition, and dependency parsing. We show that there is still room for improvement in the analyses of recipes.

## introduction today, a great number of cooking recipes are available on the internet. many people upload their recipes to recipe-sharing services such as cookpad and yummly, with cookpad having over six million recipes and yummly over two million recipes, to date. as the number of shared online recipes increases, many recipe-related datasets have been published @xcite @xcite . these datasets have successfully contributed their content to a variety of recipe-related studies about recipe understanding, recipe search, recipe generation, and so on. nevertheless, there are still few datasets that contain linguistic annotations for cooking recipes. most of the recipe studies rely on linguistic analyses, like those focusing on other text such as newspaper articles. since linguistic annotations play an important role in fundamental analyses, they are also deserving of more attention in this field. in this paper, we introduce our cookpad parsed corpus, which is a novel dataset of japanese recipes. we extract 500 recipes randomly from the cookpad recipe dataset @xcite , currently the largest recipe dataset, and annotate 4, 738 sentences in the recipes with the most fundamental linguistic information: morphemes, named entities, and dependency relations. we also report benchmark results of the corpus for morphological analysis (ma), named entity recognition (ner), and dependency parsing (dp) for japanese, and investigate whether tools or methods which have been commonly used for these analyses perform sufficiently for cooking recipes. ## related works name target documents kyoto university text corpus @xcite newspaper articles gda corpus @xcite newspaper articles and dictionary entries naist text corpus @xcite newspaper articles kyoto university and ntt blog corpus @xcite blogs kyoto university web document leads corpus @xcite web documents balanced corpus of contemporary written japanese @xcite newspaper articles, books, magazines, etc cookpad parsed corpus ## cookpad parsed corpus in this study, we constructed a novel recipe-related dataset, named cookpad parsed corpus, which contains linguistic annotations of japanese recipes. we randomly selected 500 recipes from the largest recipe dataset, cookpad recipe dataset @xcite , which contains approximately 1.7 million japanese recipes. we then annotated 4, 738 sentences (hereafter called the target sentences) in the 500 recipes with morphemes, named entities, and dependency relations. figure 1 shows linguistic annotations for an example sentence in our corpus. the lines starting with # represent the ids of the step in the recipe and the sentence in the step, respectively, while eos represents the end of the sentence. the format of our corpus is based on the kyoto university's corpora @xcite @xcite and output of cabocha, which is one of the most popular dependency parsers for japanese. we first annotated the target sentences with morphemes. in figure 1 , the lines starting with a word such as 鮭 (salmon) give its morphological information such as part-of-speech (pos), fine-grained pos, base form, reading, pronunciation, and so on. we followed the ipa dictionary @xcite to decide boundaries and pos for each morpheme because that resource is most commonly used tag description fi food (ingredient) fe food (part to be eliminated) fd food (dish) fa food (attribute) tg tool (general) ta tool (attribute) to tool (other) nd number (duration) nq number (quantity) no number (other) af action (food) at action (tool) ap action (person) sf state (food) st state (tool) sap state (person's action) x unclassified named entity for japanese ma. we also determined boundaries and pos for unknown words so that they fit the policies of the dictionary as much as possible. consequently, 62, 146 morphemes were annotated in the target sentences. we then annotated the 62, 146 morphemes with named entity tags. we annotated a further 26, 501 bunsetsus in the target sentences with dependency relations. a bunsetsu is a conventional unit of japanese that consists of one or more content words (e.g., noun) and zero or more function words (e.g., particle). the example sentence in figure 1 consists of five bunsetsus: 生 鮭は, 一口大に, 切り, 塩を, and ふる。, and the lines starting with * give bunsetsu information. for example, the 0 in the first line starting with * denotes the index of the bunsetsu 生鮭は. the 4 in 4d denotes the index of the bunsetsu ふる。, which is the head of 生鮭は, while the d denotes the type of dependency relations, such as d (normal dependency), p (coordination dependency), and a (appositive dependency). note that the index is set to -1 for the last bunsetsu in each sentence. this is because a dependency basically goes from left to right in japanese, and thus the last bunsetsu has no head bunsetsu. finally, we defined the 7 bunsetsu types in our corpus enables researchers to use the above linguistic annotations for their studies. it was designed to link with two existing datasets: cookpad recipe dataset and cookpad image dataset @xcite , which provide a variety of content such as reviews, meals, and images of the same 1.7 million recipes. as described, we extracted our 500 recipes from these recipes. this enables researchers to use not only the linguistic annotations of the 500 recipes in our corpus but also access the variety of content of the recipes in the two datasets for their studies. ## experiments finally, we present benchmark results of our corpus for fundamental linguistic analyses in japanese. in our experiments, we randomly divided the corpus into 400 recipes (3, 783 sentences) for a training set, 50 recipes (472 sentences) for a validation set, and 50 recipes (483 sentences) for a test set. then, we trained, tuned, and tested popular tools or methods for japanese ma, ner, and dp using these recipes. the results for ner are given in ## conclusion this paper introduced the cookpad parsed corpus, which contains linguistic annotations of japanese recipes. the corpus was composed of 500 recipes which were extracted from the cookpad recipe dataset. a total of 4, 738 sentences in the recipes were annotated with morphemes, named entities, and dependency relations. benchmark results on our corpus for japanese ma, ner, and dp were reported, and showed that there is still room for improvement in these analyses of cooking recipes. we believe the linguistic annotations will form a basic infrastructure not only for the improvement of the fundamental analyses, but also for the variety of recipe-related studies based on the analyses. the dataset can be obtained by sending an e-mail request to the authors. in future work, we plan to enrich our corpus with further linguistic annotations such as predicate-argument structures and co-references.