本文以2002至2012年間，獲得穆迪與惠譽信評公司給予評等的台 灣銀行爲研究對象。發現本國銀行獲得的銀行個別評等較差，而獲 得的發行體評等相對較佳，顯示信評機構認爲本國銀行的營運風險 高，但違約風險不高。政府持股比率高的銀行，獲得較差的穆迪銀 行財務強度評等及惠譽的銀行個別評等，表示信評機構將政府持股 比率較高的銀行視爲營運風險較高。當銀行規模愈小，信評機構視 爲違約風險較大，但大規模銀行則無論政府持股高低，不影響違約 風險。信評機構評估銀行獲得外部援助的程度，將政府持股比率超 過20%的大銀行視爲出事時可以獲得較多的外部援助。

This paper uses banks assigned ratings by Moody's and Fitch from 2002 to 2012 as our sample and uses individual ratings as proxies for operational risk and issuer ratings as proxies for default risk. The results show banks in Taiwan obtain better individual ratings and worse issuer ratings, suggesting higher operational risk but lower default risk. Banks with higher government ownership obtain worse individual ratings, suggesting higher operational risk. Small banks face higher default risk and large banks have lower default risk no matter the ownership structure. Banks with more than 20% government ownership can obtain more external support.