The survey started from the day after the government announced the proposal (April 23) and will continue up to the day before the LegCo casts its vote. Hong Kong citizens of 18 years old or above who speak Cantonese are interviewed by real interviewers through random telephone interviews.
Telephone numbers are randomly generated by the three institutes respectively using known prefixes assigned to telecommunication services providers under the Numbering Plan provided by the Office of the Communications Authority (OFCA). After eliminating invalid numbers, the three sets of numbers generated are combined and then randomly assigned to the three institutes again to produce the final sample.
The interviewers first ask the respondents whether they “support or oppose the government’s proposal on CE election of 2017” and also collect their demographic information, including sex, age, education level and political preference.
No less than 200 samples are collected each day, giving over a rolling sample of 1,000 for 5 days, after which the rolling sample is complete and aggregate analysis will be conducted.
The findings of the survey 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 2014 year-end and the educational attainment (highest level attended) distribution collected in the 2011 Census.