報告書番号

N05034

タイトル（和文）

災害時における住民生活を対象としたライフライン途絶回避便益の評価 -仮想市場評価法（CVM）に基づく複数供給系ライフライン長期途絶回避に対する支払い意思額の推計とその要因分析-

タイトル（英文）

Evaluation of benefits of residents brought by avoiding lifeline disruption during a disaster- Estimation of willingness-to-pay to avoid long-term multiple supply-type lifeline disruptions by contingent valuation mdethod (CVM)

概要 （図表や脚注は「報告書全文」に掲載しております）

本研究では，複数ライフラインの長期的な途絶に対する住民への経済影響を定量化するために，仮想市場法（CVM）型の調査設計を行った．この際，途絶が長期化した場合に補償が得られるオプションを設定したライフライン途絶回避・延期オプション選択モデルを設定した．さらに，調査手法を対象とする地域に適用し，各世帯のオプション選択行動および途絶回避への支払い意思額を分析した．推計の結果，幼齢者の有無やオール電化などのライフライン関連施設の影響が意思決定に有意な影響を与えていることや，他のライフラインが途絶した状況における電力の供給価値は電力が単独で途絶した場合よりも大きくなるなどの知見が得られた．

概要 （英文）

In recent years, we have experienced many accidents occurring in lifeline systems such as electricity, water and gas. For example, large blackouts occurred in North America and Italy in 2003. In Japan, the Mid-Niigata Earthquake occurred in 2004 and lifeline systems including road network, sewage and telecommunication systems were simultaneously damaged. These events provide us with the opportunity to reconsider the importance of lifeline systems in our urban lifestylecity life, how to protect them and how much risk we can absorb in. This research aims to analyze willingness-to-pay (WTP) of residents to avoid lifeline disruptions and influencing factors on the WTP by CVM (contingent valuation method). The disaster scenarios are determined such that multiple lifelines (electricity, water and gas) are simultaneously disrupted for a long period. Residents’ behaviors to the disaster scenarios are statistically analyzed by the discrete choice model, which is based on the random utility model. The model makes comparison of utility levels of residents among three options; whether to avoid with cost-burden, to extend with compensation, or to accept the proposed hypothetical lifeline disruptions without any actions. As a result of estimating the models, disaster scenarios and proposed cost-burden significantly influence on residents’ behavior and their coefficient values and sign conditions meet with the theory of indirect utility function and the hypothesis that WTP becomes larger as the disruptions scenario becomes severer. This condition holds in case that we have enough sample size. It is also shown that small children and lifeline related facilities, such as electric-use-only type of house, significantly influence on the decision-making of selecting the options. Estimated WTPs demonstrate that electricity-supply in the case that other lifelines are disrupted is more valuable than the case that other lifelines are supplied.

報告者

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