The Changes and Trends in Telephone Household Coverage

For almost three decades telephone household surveys have increased in number and size. There has been a corresponding development of telephone sampling techniques that attempted to improve the cost effectiveness of telephone surveys. For example, the twostage RDD sampling devis ed by Mitofsky (1970) and revised by Waksberg (1978) provided nearly complete coverage of both listed and unlisted telephone households while improving the ability to locate telephone households. Furthermore, telephone household surveys advanced as fixed telephone household coverage (FTHC) increased. A number of studies examined the nature of telephone household noncoverage. Collins (1987) dealt with non-coverage problem by non-ownership of the telephone in several countries such as the United States (US) and the United Kingdom (UK). Trewin and Lee (1988) made international comparisons of telephone household coverage around the world. Thornberry and Massey (1988) examined to the issue of telephone household non-coverage bias in the US. In recent years, the growth of mobile service sector raised a potential threat to the improved coverage of telephone household surveys. Mobile service provides customers advantages in convenience, rather than price, compared to fixed line service. In many countries at present, there has been a decrease in fixed line coverage of households as pre-paid and other types of mobile service. For example, Kussela and Vikki (1999) found that FTHC in Finland has seriously decreased during last decade due to an increase of households that use mobile service as an alternative to fixed line. Nathan (2001) observed that this trend has been recently occurrng in several European countries such as UK, Israel, and Germany. Steeh and Cannon (2000) examined mobile telephone ownership in the state of Georgia in the US, and expressed concerns about a similar trend arising in the US. Kim and Lepkowski (2002) investigated the effects of increased mobile service on fixed line service, and concluded that there is a trend globally of decreased coverage of fixed line telephone households due to an increase in mobile only households. In this paper, we examine the relationship between fixed line and mobile service penetration rates in 12 countries, and attempt to link penetration rate to FTHC. Hierarchical multivariate linear models (Raudenbush, Bryk, Cheong, and Congdon, 2000) are used to analyze the relationship between FTHC and mobile penetration rates at a country level.