Yuya Shibuya

• PhD
• Associate Professor at The University of Tokyo

This book explores the possibility of using social media data for detecting socio-economic recovery activities. In the last decade, there have been intensive research activities focusing on social media during and after disasters. This approach, which views people’s communication on social media as a sensor for real-time situations, has been widely...

Civic tech initiatives dedicated to environmental issues have become a worldwide phenomenon and made invaluable contributions to data, community building, and publics. However, many of them stop after a relatively short time. Therefore, we studied two long-lasting civic tech initiatives of global scale, to understand what makes them sustain over ti...

In the last decades, researchers in Human-computer interaction (HCI) took numerous efforts to investigate people's social media interaction. To understand how researchers in HCI have studied social media interaction, we examined 149 peer-reviewed articles published between 2008 and 2020 in major HCI conference proceedings and journals. We systemati...

Data are essential for digital solutions and supporting citizens’ everyday behavior. Open data initiatives have expanded worldwide in the last decades, yet investigating the actual usage of open data and evaluating their impacts are insufficient. Thus, in this paper, we examine an exemplary use case of open data during the early stage of the Covid-...

Given the worldwide increase of forcibly displaced populations, particularly internally displaced persons (IDPs), it’s crucial to have an up-to-date and precise tracking framework for population movements. Here, we study how the spatial and temporal pattern of a large-scale internal population movement can be monitored using human mobility datasets...

The Weizenbaum Institute organised its sixth Annual Conference on the topic of “Uncertain journeys into digital futures” in Berlin in June 2024. The conference focused on the challenge of the digital transformation and the socio-ecological transformation of society which are closely interlinked and crucial for prospering futures of humanity. Challe...

In recent years, the explosion of extensive geolocated datasets related to human mobility has presented an opportunity to unravel the mechanism behind daily mobility patterns on an individual and population level; this analysis is essential for solving social matters, such as traffic forecasting, disease spreading, urban planning, and pollution. Ho...

This study compares place-based and individual-based segregation under different contexts in the Tokyo metropolitan area. Segregation level varies with individuals’ household income and activity space type. Segregation level is lower in the working and routine activities space than in residence and nonroutine activities space. The higher the indivi...

In this perspective article, we propose an interdisciplinary research agenda that addresses citizen science approaches embedded in civic tech initiatives and citizen sensing scenarios. The proposed agenda builds on the multi-level perspective framework (Geels, 2004; Geels, 2019) to inform research on how such ‘niche innovations’ like citizen sensin...

The term _values_ is prominent in political discourse. Yet its ubiquity is matched by its vagueness, especially when considering usage among different cultures. Twitter provides a promising venue for exploring the contested political discourse surrounding this term. In this paper, we study the use of the term values on Twitter across different lang...

Civil society organizations (CSOs) in cities and communities have used available civic data by citizens and for citizens to tackle local pressing issues, e.g. on mobility issues. To make civic data actionable, however, civic data collection alone is not sufficient: data needs to be made actionable and communicated as part of new participatory struc...

The goal of this chapter is to provide a brief summary of the related literature regarding “people as sensors” and to propose a conceptual study framework for this book. A variety of studies have tried to use social media to improve situational awareness based on various approaches. Although, as discussed in Chap. 1, there is a possibility of using...

The goal of this chapter is to show the appropriateness of using used-car market data as a proxy of one of the socio-economic recovery activity indicators after the Great East Japan Earthquake and Tsunami (RQ1a). In Chap. 2, the author describes the news reports and the interviews with used-car dealers which revealed people in the disaster-impacted...

In this chapter, the author examines whether there was an excess demand for housing after the Great East Japan Earthquake and Tsunami. In other words, this chapter investigates the possibility of using the housing market data as one of the proxies for socio-economic recovery activity indicators (RQ1b). As described in Chap. 3, various studies relat...

The goal of this chapter is to investigate correlations between topics on Facebook Pages and excess demand for used cars after the Great East Japan Earthquake and Tsunami. Because Chap. 4 revealed that there was excess demand for used cars, particularly Light Motor Vehicles (LR, LC, and LT), this chapter uses the excess demand for used cars as a pr...

In this chapter, the study investigates correlations between excess demand for used cars and public sentiment on social media communication after the Great East Japan Earthquake and Tsunami (RQ2). The results of this investigation suggest that there were statistically significant correlations between people’s sentiment on Twitter and the excess dem...

In the previous Chaps. 6– 8, the study’s focus was on excess demand for used cars. In this chapter, this study focuses on excess demand for housing, which can be used as a proxy of the socio-economic recovery activities as discussed in Chap. 5. Particularly, this chapter analyzes correlations between social media communication and the socio-economi...

In this chapter, the study investigates correlations between excess demand for used cars and topics on Twitter after the Great East Japan Earthquake and Tsunami. Based on the methodology described in Chap. 3, the author conducts Latent Dirichlet Allocation (LDA) with Twitter data after the Great East Japan Earthquake and Tsunami of 2011 and address...

The goal of this chapter is to demonstrate there was excess demand for dry houses after Hurricane Sandy in New York City, and thus to support the appropriateness of using housing market data as a proxy of one of the socio-economic recovery activity indicators (RQ1b). This chapter, therefore, examines how the housing market data in New York City was...

In this chapter, the author quantitatively analyzes the relationships between public sentiment on social media, Twitter, and one of the socio-economic recovery indicators as reflected in housing market data after Hurricane Sandy (RQ2). Based on the methodology presented in Chap. 3, the author collects tweets posted by people who were in New York Ci...

There has been growing interest in harnessing Artificial Intelligence (AI) to improve situational awareness for disaster management. However, to the authors' best knowledge, few studies have focused on socio-economic recovery. Here, as a first step toward investigating the possibility of developing an AI-based method for detecting socio-economic re...

Enhancing situational awareness by mining social media has been widely studied, but little work has been done focusing on recovery phases. To provide evidence to support the possibility of harnessing social media as a sensor of recovery activities, we examine the correlations between topic frequencies on Twitter and people's socioeconomic recovery...

The aim of this paper is to examine how a large-scale natural disaster impacts on the used-car market. This paper particularly tries to clarify what type of cars and what kinds of car features were demanded in damaged areas and when. We conduct a case study on the Great East Japan Earthquake and Tsunami of 2011 and compare the used-car prices in da...

When a large-scale disaster hits a community, especially a water-related disaster, there is a scarcity of automobiles and a sudden increase in the demand for used cars in the damaged areas. This paper conducts a case study of a recent massive natural disaster, the Great East Japan Earthquake and Tsunami of 2011 to understand those car scarcities an...

There have been various studies analyzing public sentiment after a large-scale disaster. However, few studies have focused on the relationship between public sentiment on social media and its results on people's activities in the real world. In this paper, we conduct a long-term sentiment analysis after the Great East Japan Earthquake and Tsunami o...