本文使用月追蹤資料檢視本國銀行的信用卡利率行為及其與信用卡逾期放款之關係，以檢定信用卡利率之訂定是否與銀行資金成本、資訊不對稱、逆選擇問題及信用卡的轉換成本、營運規模、業務強度和信用風險有關，發現：信用卡利率調整行為不會受其營運規模、信用風險和銀行資金成本影響，意味信用卡利率決策不合理；信用卡利率與業務強度呈負相關；調降利率和銀行間利率差異並未導致逆選擇問題；轉換成本是利率居高不下的可能原因，而資訊不對稱程度不一可解釋銀行間的利率差異。

This paper aims to test whether the pricing of credit-card interest rates depends on banks' capital costs, information asymmetry, adverse selection as well as credit-card switch costs, operating size, business intensity, and credit risks. Employing regression analysis with panel data on monthly frequency, this study examines the interest rate behavior of credit cards in Taiwan's banks and the relationship between interest rate behavior and nonperforming loans for credit cards. The findings are that credit-card operating size, credit risks and bank's costs of capital have not affects on credit-card interest rate behaviors, indicating the pricing of credit card rates is unreasonable; there is a negative relation between credit-card rates and business intensity; decreasing in interest rates for a bank and difference in interest rates across banks do not cause adverse selections. Moreover, the switch costs may lead to the stickiness on high levels for credit card rates, and the distinct degrees of information asymmetry across banks possibly explain different interest rate behaviors of banks.