 Hi, I'm Peggy Kim, nice to meet you all. Today I want to talk about controversies over historical revisionism in Wikipedia. Historical revisionism refers to the reinterpretation of historical events. In recent years, revisionism driven by right-wing populism has become more visible in many countries and it can impact the dissemination of certain historical perspectives. However, our understanding of this phenomenon is still very limited. So in this study, we aim to investigate the recent development of revisionism using Wikipedia data. Wikipedia is an idea platform to investigate this. Although it must be written from a neutral point of view, edits can be driven by the editor's ideology. As all edits are recorded, we can trace the dynamics of these activities. So this project focuses on the Japanese case. So in Japan, there has been a rise of radical right-wingers and they have disseminated revisionist claims. Since their claims focused on events on World War II and related topics, we also focus on these topics in this study. So this study aims to address these three questions. What types of historical topics are most susceptible to historical revisionism? And what are the common factors for the historical topics that are subjected to revisionism? And are there a group of editors who are seeking to disseminate revisionist narratives? So let's begin with the first question. What types of historical topics are most susceptible to historical revisionism? To identify the articles that are subjected to revisionism, we focus on the level of controversy of articles because it is likely that revisionism introduces edit words. So we expect articles with a higher level of controversy are more likely to be subjected to revisionism. To determine article categories that are more susceptible to revisionism, we compare the levels of controversy across different categories of articles. To measure the controversiality, we rely on M measurement that focuses on editors' mutual reverts. Mutual reverts are situations that two editors revert each other's edits, and it considered as a key feature of controversiality. So we collected about the 74,000 articles on Japanese history. So we used a general category, history of Japan, and three of war-related categories, Japanese war crime, Japan support for settlement, and Pacific war. We also used a portal page introducing articles related to the war and the perception towards events. Because these articles are curated by a group of editors, we expect that they are at the center of the topic and therefore potentially more contentious. And this plus shows the average M score by categories. So E is a portal page, and as we expected, it shows a high level of controversy. But also these war-related categories, BCD showed a significantly higher level of controversy than general historical articles. Then what are the common factors for these articles? To answer this question, we examined the most controversial articles belongs to the war-related categories. We selected them as our target articles and examined their talk faces and most contentious texts. So these are our target articles, and we found two notable features, war crimes and writing ideology. So five of them are related to war crimes, and as for writing ideology, reverted texts in these articles are related to the claims made by far-right organizations. And this shows the development of the target articles. Although each article has a different development pattern, overall, the controversy level and number of contributing editors have increased over time. So our last question is, are there a group of editors who are seeking to disseminate revisionist narratives? If there are, they're kind of editors, they will probably contribute to a wide range of controversial topics. And they were involved in edit-based. So our strategy is to compare the average number of articles contributed by editors who have been involved in edit-based with other editors for the target articles. So editors who involved in edit-based means those who are mutually reverted in our article samples. If there are groups of editors interested in disseminating revisionist ideas, these mutually reverted editors will show a significantly higher level of participation in the target articles. This is a t-test results, and indeed, mutually reverted users show the significantly higher level of participation in the target articles. It suggests the possible presence of editors seeking to disseminate revisionist ideas. And these are similarity networks of the target articles based on the overlap of contributing editors. And it also supports the previous finding. When there is an edge, when there is an edge, these two articles share the same editors. When we consider all editors in this graph, we see only two connections, but when we consider only mutually reverted editors, we see a big cluster of articles. So here is the conclusion. The wall-related articles showed a high level of controversy. Among them, the top controversial articles are related to war crimes and right-wing ideology. The level of controversy and contributing editors increase over time. And editors who are involved in the edit world were more likely to contribute to controversial articles, and this suggests a possible presence of editors seeking to disseminate revisionist narratives. Thank you for listening.