"Address book" of cellular phones as index of the size of personal network

Abstract

The purpose of this study is to examine the validity and possible measurement bias of the number of acquaintances registered on the "address book" of cellular phones (address book size) as the index of the size of personal network using national survey data. The first objective is to reveal who uses address book and results showed that 1) only 60 percent of respondents uses address book, 2) the utilization rate is higher when the respondents are younger, highly educated, having high income, or living in urban areas. Respondents' age and income has stronger impact on the utilization than the other factors. The second objective is to examine the external validity of address book size as the index of the size of personal network. Result shows that the estimate of telephone book method positively correlates with address book size. The correlations are stronger when the respondents are living in urban areas. Respondents ' age does not moderate the correlation.