2016 Legislative Council Election Follow-up SurveysBack

Research Background

The Public Opinion Programme (POP) at The University of Hong Kong conducted two follow-up surveys on the 2016 Legislative Council Election in September, by means of random telephone surveys conducted by real interviewers, and successfully interviewed 519 and 512 voters of Legislative Council Election on 4 September 2016 respectively. The objective was to gauge actual voters’ views on Legislative Council Election and their voting behavior.

The survey was self-funded by POP, the research instrument used was designed entirely by the POP Team. Fieldwork operations and data analysis were also conducted independently by the POP Team, without interference from any outside parties. In other words, POP had full autonomy to design and conduct the survey, and POP would take full responsibility for all the findings reported herewith.

Research Design

Telephone interviews were conducted by telephone interviewers under close supervision. All data were collected by interviewers using a Web-based Computer Assisted Telephone Interview (Web-CATI) system invented in-house by the research team, which allowed real-time data capture and consolidation. To ensure data quality, on top of on-site supervision and random checking, voice recording, screen capturing and camera surveillance were used to monitor the interviewers’ performance.

Telephone numbers were randomly generated using known prefixes assigned to telecommunication services providers under the Numbering Plan provided by the Office of the Communications Authority (OFCA). Invalid numbers were then eliminated according to computer and manual dialing records to produce the final sample.

The target population of the survey was actual voters of Legislative Council Election on 4 September 2016. After telephone contact was successfully established with a target household, one eligible person was selected using “next birthday rule” for the interview. The first survey of telephone interviews were conducted during the period of 12 to 14 September, 2016. A total of 519 voters were successfully interviewed. The effective response rate of this survey was 69.3%, and the standard sampling error for percentages based on this sample was less than 2.2 percentage points. In other words, the sampling error for all percentages using the total sample was less than plus/minus 4.4 percentage points at 95% confidence level. The second survey of telephone interviews were conducted during the period of 19 to 21 September, 2016. A total of 512 voters were successfully interviewed. The effective response rate of this survey was 74.2%, and the standard sampling error for percentages based on this sample was less than 2.2 percentage points. In other words, the sampling error for all percentages using the total sample was less than plus/minus 4.4 percentage points at 95% confidence level.

To ensure representativeness of the findings, the raw data (of about 1,400 Hong Kong residents of age 18 or above) have been rim-weighted according to provisional figures obtained from the Census and Statistics Department regarding the gender-age distribution of the Hong Kong population in 2016 mid-year and the educational attainment (highest level attended) distribution collected in the 2011 Census. Then among them, 519 and 512 voters of Legislative Council Election on 4 September 2016 were selected respectively and adjusted its weighted proportion.