• The Korean Journal of Applied Statistics
• /
• v.29 no.5
• /
• pp.787-806
• /
• 2016

Mixed-mode (MM) designs in which data are collected by different modes in one design have become increasingly popular. An MM data collection has several advantages such as reductions of coverage error, non-response and cost. However, MM designs may introduce mode effects that are confounded by selection effects and measurement effects, which can make MM data quality poor. In order to investigate mode effects, SRI implemented a concurrent mixed-mode experiment in 2014 where respondents could choose between a self-administrated Web survey and a self-administrated paper survey. This paper separately estimates selection effects and measurement effects. We found that measurement effects on some items are large.

• Journal of Navigation and Port Research
• /
• v.40 no.3
• /
• pp.89-95
• /
• 2016

S-Mode is a concept involving a standardized navigation display with accompanying standardized functionality and interfaces for navigational equipment. It was proposed by the International Federation of Shipmasters' Associations at IMO NAV $54^{th}$ session in 2008. The IMO e-Navigation Strategy Implementation Plan(SIP) addresses, S-Mode and the IMO MSC at its $95^{th}$ session in 2015 approved an output 1 to develop S-Mode guidance. In this study, it has been carried out survey of user needs for adopting S-Mode guideline on ECDIS which is core navigational equipment. It is conducted with a questionnaire survey, targeting deck officers and masters who will be the primary users of the equipment related to the e-Navigation system. In this research, users' opinion survey regarding the necessity of development, the scope of standardization, and priorities was conducted. This survey result could be contributed to development S-Mode guideline and specify the concept of S-Mode. It would be derived from standardizing component through providing elements to be considered for its development.

• Asian Journal for Public Opinion Research
• /
• v.1 no.1
• /
• pp.26-41
• /
• 2013

The rise and fall of social research methods rely on how much a certain method is able to appropriately reflect the change of society. The present research proposes new mobile surveying methods, considering the current and future trends in Korea. In particular, this research focuses on environmental pressure (time constraints, the presence of others and the place) as one of the major factors influencing the effects of survey modes. For example, landline surveys are conducted in the respondent's home, which is a private and fixed space. On the other hand, surveys on mobile phones can be conducted in diverse places with other people around. After sampling 500 landline respondents and 500 mobile phone respondents using a quota method, the same questionnaire was used for both the mobile and landline interviews. The findings are generally consistent with the literature supporting the data quality and comparability of the mixed mode survey. These results are encouraging for researchers designing surveys that feature mobile phone data collection.

• Asian Journal for Public Opinion Research
• /
• v.1 no.2
• /
• pp.147-150
• /
• 2014

Mixed-mode (or multi-mode) surveys and (volunteer) web panels were recently introduced as ways to cope with changes in the social survey environment, which is going through a rapid and massive transformation. The direction, speed, and magnitude of these changes have been clear in Korea, too. Enumerated in Figure 1 are the social surveys between 1960 and 2010 archived by the Korean Social Science Data Archive (KOSSDA) 2. The left panel shows the exponential growth in the overall volume. The other two panels, more importantly, show the changes in the composition. Mixed-mode and online surveys are rapidly increasing their shares and are fast becoming de facto standards in Korea, as in many other countries.

• Journal of Sasang Constitutional Medicine
• /
• v.29 no.3
• /
• pp.224-231
• /
• 2017

Objectives Several researches have been done to develop instruments or questionnaire for diagnosis of sasang constitution. In this study, we developed a user-friendly web system to enhance the utilization of KS-15. Methods The KS-15 Web application was constructed by considering the responsive web design and easy survey answer. This system is designed only to authorized users for security purposes, and provides two modes, simple mode and expert mode, depending on the purpose of using the system. A simple mode do not keep user information and survey answer in the database. An expert mode support management of patients, diagnosis of sasang constitution and statistical functions. Results & Conclusions The developed KS-15 system can be operated from any smart device's web browser. In order to use information in clinic field, it was developed so that it can be accessed only by authorized users. It can be divided into an account which can use only simple mode and an account which can use expert mode by using a difference in access authority. These functions can enhance the applicability of sasang constitution in real life such as clinical or education.

• Survey Research
• /
• v.12 no.3
• /
• pp.1-23
• /
• 2011

Regarding the growing concern for the mixture of landline and web-based/mobile survey, researchers are increasingly interested in methodological examination of anticipated benefits and problems of mixed mode surveys. This study focuses on scale construction. Multiple questions with a multi-point scale have been preferred in traditional surveys. However, it is not obvious if those scales have advantages also in a web-based survey. We tested if, in a web-based survey, validity, reliability, and easiness of response differ according to the size of scales.

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

• Journal of Korean Society of Transportation
• /
• v.28 no.3
• /
• pp.99-107
• /
• 2010

Analyzing mode choice among transportation demand estimate procedures is complicated and understanding characteristics of travelers is also difficult. Generally, it is well known that traveler choose mode considering psychometric factors and characteristic besides socio-demographic indicators. Accordingly, many researches has investigated on methodology that can be applied in mode choice to reflect psychometric factor or specific preference. Latent Class Analysis among various studies is recognized as the theoretically potential approach. This study focuses on class segmented using latent class cluster to analyze impact that included psychometric factors and characteristics on mode choice. It also provides evidence that mode choice model for each class and mode choice model not considering latent class are different. This study based on citizen's stated preference and revealed preference on a new transit on the Han river shows that latent class cluster analysis is the potential approach considering latent preference.

• Proceedings of the KSR Conference
• /
• 2002.05a
• /
• pp.35-40
• /
• 2002

The Korean high speed railway system is scheduled to open sometime in 2004. To fulfill its duties, it is essential to view intermodalism in easy access to high speed railway station. To study travelers' choice of mode and to make improvements the transfer, a SP survey of 3628 was conducted in national level in the fall of 2001. An understanding of KTX passenger mode choice is crucial for station-related facility capacity planning. Development of main and regional high speed stations, as well as changes in the roadway and railroad transportation system for station access, will influence the relative demand for traveling by train from compel ing other transportation mode. The research described here was designed to derive a general overview of the basic travel patterns with an emphasis on intermodal transportation system.

• The Korean Journal of Applied Statistics
• /
• v.25 no.1
• /
• pp.153-162
• /
• 2012

We proposed a mixed-mode design with a landline survey and mobile survey as the solution for the problems of election opinion polls by the original telephone survey method, mostly with limited population coverage for young people not living at home and with lower efficiency in selecting valid voters. We numerically verified the applicability of the proposed dual frame survey by analyzing the preliminary opinion poll results of the Seoul mayor by-election of October 26 2011. This research achieved the result that relative standard errors were similar between a mobile RDD sample and landline RDD sample though the variance was bigger in the former. Though the combination of mobile RDD and landline RDD is not found to improve the forecast accuracy, it still is expected to have higher reliability for election polls by expanding the population coverage and compensating the weakness of each survey method.