• Survey Research
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• v.9 no.1
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• pp.1-22
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• 2008

Telephone directories ille still being used as the sampling frame in almost all fixed-line telephone surveys in Korea, causing potentially serious coverage error. RDD (random digit dialing) sampling is an obvious alternative to solve the problem. The aim of this paper is twofold: 1) proposal of RDD methodology suitable to the telephone system of Korea and 2) the identification of socio-demographic and socio-psychological differences between listed-number and unlisted-number respondents. Major findings of RDD telephone survey conducted experimental]y are as follows. 1) Population coverage by telephone directories is 60% or less. 2) Unlisted-number households have statistically larger income compared to listed-number households. 3) Unlisted-number households have smaller family size compared to listed-number households. 4) Unlisted-number respondents are more sensitive about confidentiality, leaks, 5) Unlisted-number respondents are more liberal compared to unlisted-number respondents. These facts suggest that directory-based telephone surveys tend to be biased in socio-economic aspects.

• Survey Research
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• v.5 no.1
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• pp.1-26
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• 2004

The aim of this study lies in answering the question "How to form weighting cells to enhance sample representativeness in telephone, Internet and mobile surveys\ulcorner". For this, we explored 2% raw data of Year 2000 Population and Housing Census of Korea looking for meaningful patterns for ownership of telephones, the usage of Internet and/or mobile phones. We found that telephone coverage rates vary significantly by household size; 84.6% for one member households, contrasting 98.5% for two-or-more member households. Thus, telephone survey samples need to be weighted differently in sub-groups by household size for proportional representation of target population. Searching socio-demographic factors influencing the use of Internet by C5.0 tree models, we found that education levels and the occupation (or housing type, the automobile ownership) are two most important factors in addition to gender and age. Thus, surveyor might form weighting cells by such factors at the stage of post-stratification or set quotas, a priori, proportional to size of the cells by such factors. For mobile surveys, we approached similarly and found that education levels and the occupation (or the automobile ownership, marriage status) are two additional factors that may be used in forming weighing cells or in setting quotas for cells.

• Survey Research
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• v.9 no.3
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• pp.55-69
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• 2008

In most telephone surveys in Korea, telephone numbers are selected from the directories. Inevitably, such samples may lack representativeness due to poor coverage rate. To resolve the problem, Kang et al.(2008) implemented RDD(random digit dialing) method for nationwide sampling in Korea. The aim of this study is to compare an RDD sample with a traditional telephone quota sample that were collected independently by two survey institutes commissioned by the KBS-MBC consortium for the 2007 Presidential Election of Korea.

• Survey Research
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• v.12 no.2
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• pp.77-88
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• 2011

Korean telephone surveys have been based on telephone directory and thus criticized for considerable under-coverage. Now, Korean survey institutions progress to random digit dialing (RDD) very actively. But still most surveys are administered by quota sampling, prone to assign heavier weights to social classes with more hours staying indoor. As a practical remedy, time-balanced quota sampling scheme was proposed by Huh and Hwang (2006). This study compares two telephone surveys on TV audience environment in Korea: RDD with conventional quota sampling versus RDD with time-balanced quota sampling.

• Asian Journal for Public Opinion Research
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• v.3 no.3
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• pp.111-130
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• 2016

Researchers have been perplexed by the issue of unit nonresponse since the beginning of practicing survey research and have been attentive to the causes that lead to the occurrence of unit nonresponse as well as the impact of unit nonresponse. However, because researchers have little to no information regarding unit nonrespondents, it is unlikely that they are able to examine the differences between participants and nonrespondents to estimate the loss of representativeness in the final sample compared with the target population. Therefore, the lack of information regarding the absentees complicates addressing the unit nonresponse bias in a satisfactory manner. Therefore, the purpose of this study was to determine the demographic characteristics and political attitudes of nonrespondents by relying on information provided by their spouses, which was obtained through a telephone survey conducted in Taiwan. It is found that demographic variables as well as political attitudes are related to the likelihood of an individual becoming a unit nonrespondent in telephone surveys.

• Survey Research
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• v.3 no.2
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• pp.77-90
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• 2002

This study reports the results of a random sampling telephone survey conducted in the case of the Ulsan mayoral election 2002. We interview at least five times to a respondent who is randomly selected by means of the birthday method from a randomly sampled telephone number list of 1,233 households, We analyze the result of interviewing, such as absence and promise. And we compare the demographic variables of the surveyed sample and those of the population and we also compare the randomly selected sample's voting preference with outcome of the election in various ways. Finally, we discuss difficulty of random sampling with the birthday method and suggest some technical tips to conduct random sampling telephone survey.

• Survey Research
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• v.1 no.1
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• pp.21-43
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• 2000

Although telephone surveys are an attractive alternative to household interviews it is important to determine whether the data collected by the two methods are comparable. To answer this question, findings from the telephone survey literatures are examined in the view point of i) direct effect which means expressions of preference of the interview detail of answers on open questions and item missing data rates ii) statistical estimates and iii) differences of interviewers and data collection modes. Differences are explained by social desirability effects on the telephone, cognitive ability of the survey question, and mode effects and interviewer effects.

• Proceedings of the Korean Association for Survey Research Conference
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• 2002.11a
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• pp.241-253
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• 2002

Since the 1980's, telephone surveys have been widely used in the world due to a rapid spread of fixed telephones and the development of a variety of sampling techniques. Telecommunications technology has rapidly developed since the early 1990's, and the number of mobile phones grew rapidly in most countries. Also, it has dramatically increased over the last few years. With the growth of households that abandon fixed telephones and move to a mobile only status, fixed telephone household coverage rates are currently decreased in many countries. In this paper, we take a look at the changes and trends in fixed telephone households coverage rates in the European Union, Asia including South Korea, and North America, and deal with the coverage problems in telephone surveys to be faced even in Korea.

• Survey Research
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• v.10 no.1
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• pp.57-72
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• 2009

In Korea, telephone surveys have been used in election forecasting since 1992. In some elections, predictions were excellent, but in some elections, the predictions based on telephone surveys were not good. So, exit polls have been used along with the telephone surveys in predicting election outcomes since 2001 by the major broadcasting networks. Though telephone surveys, in general, have been less accurate than exit polls in election forecasting from 2000 to 2003, they were more accurate in the 2004 General Election than the exit polls. All predictions on the winners by the telephone surveys turned out to be accurate. But such success has not persisted. In the 2008 General Election, the telephone surveys was less accurate than the exit polls and actually its accuracy fell clown to the level of the 2000 General Election. This paper tried to find out. the factors responsible for the fluctuation of the accuracy of telephone polls.

• Survey Research
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• v.11 no.2
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• pp.141-160
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• 2010

This study aims to analyze the usefulness of the survey procedures developed for telephone surveys using a random sampling method. We conducted a telephone survey of residents in a local area from October 26 to November18,2009. We applied random sampling procedures with five call-backs. Particular attention was given to the conversion of refusals. Out of 2,454 phone numbers, we succeeded in getting responses from 637 numbers. The absence of residents was the primary cause of non-response. We received responses from 45.7% of those with whom we successfully made contact. One finding of this study is that, contrary to our initial expectations, call-backs do not significantly increase the percentage of responses from young people. Also we cannot find any significant differences in responses to various questions between the responses received from the first round of calls and later responses. However, these results are not conclusive; another survey may produce different results. Therefore, further research is needed.