Information Balance between Transmitters and Receivers Based on the Twitter after Great East Japan Earthquake

In this paper, Information Balance between supply and demand of information is considered. In general, differences between informational transmitter and receivers are often observed, and it is not so surprising in daily life. However, it would give serious influences for the receivers to make decisions about their next action in the emergency situations like disasters. In this paper, the government is assigned a role as the informational transmitter and the citizen have roles of the receivers. This paper is to find out supply and demand of information (“Information balance”) between government and citizens regarding Great East Japan Earthquake and Fukushima Nuclear Power Plant accident. Information from Government is picked up from tweets of @kantei saigai, official twitter account of Prime Minister’s Office, and total 56 accounts whose profiles have some relationship to the affected area are collected as receiver. According to several analysis performance, we found out following three points. 1) There were information imbalance between government and citizens related to the affected area, 2) citizens required not only objective data about radiation but also impact and countermeasure for that, 3) citizens covered that information imbalance by following media twitter accounts providing prefectural and specific information.