이동전화가입자의 음성통화와 문자메시지 이용행태에 관한 실증연구: CES 효용함수를 이용한 대체탄력성의 추정

초록

This study, exploiting the data from 2001 to 2006, conducts an empirical analysis of the determinants of mobile phone users' relative choice between voice telephony and short message services(SMS) to confirm the substitutability between them within the mobile telephony. In contrast with the previous researches depending upon the cross price elasticity to check out the substitutability, this study directly estimates the elasticity of substitution by assuming the CES utility function for users. The outputs of this study confirm that there exists a significant substitutability between voice telephony and SMS, and explanatory variables for users' habit, relative price, income and time exert significant influences on the relative usage pattern between voice telephony and SMS. It suggests that SMS usage relatively grows vis-a-vis voice telephony, as the relative price of SMS to voice telephony falls, the level of income falls, and time passes. It is particularly noteworthy that (i) the usage ratio of SMS to voice telephony in the current period may be explained largely by that in the previous period, i.e., lagged variable of the usage ratio, revealing that users' prior habit formation plays a critical role in users' current pattern of choice between voice telephony and SMS; and (ii) as time goes by, the explanatory power of the relative price variable, i,e., the elasticity of substitution between voice telephony and SMS, diminishes, while that of the lagged variable grows.

키워드