Contact information返回

  Date of survey : 14-19 January 2009
  Survey method : Telephone survey with interviewers
  Target population : Local working population of age 18 to 65 with a monthly personal income no less than $8,000.
  Sampling method :
The contacts were successfully established with a target household, one target respondent was selected. If more than one subject had been available, selection was made using the "next birthday rule" which selected the person who had his/her birthday next from all those present.
  Sample size : 503 successful cases
  Overall Response rate : 75.4%
  Std. sampling error : Less than 4.5%

Table 1 Calculation of effective response rate

   Overall Response rate
= [ Successful cases / (Successful cases + Partial interview + Refusal cases by eligible respondents + Refusal cases by prorated-eligible respondents) ]
= [ 503 / ( 503 + 9+ 13 + 242[(503 + 9 + 13) / (503 + 9+ 13 + 370)]* ) ]
= 75.4%
*Figure obtained by prorata

Table 2 Breakdown of contact information of the survey

 

Frequency

Percentage

Respondents' ineligibility confirmed

3,822

38.7%

Fax/ data line

409

4.1%

Invalid number

2,667

27.0%

Call-forwarding/ mobile/ pager number

48

0.5%

Non-residential number

309

3.1%

Special technological difficulties

19

0.2%

No eligible respondents

370

3.7%

 

 

 

Respondents' eligibility not confirmed

2,621

26.5%

Line busy

155

1.6%

No answer

1,861

18.8%

Answering device

108

1.1%

Call-blocking

62

0.6%

Language problem

175

1.8%

Interview terminated before the screening question

242

2.4%

Others

18

0.2%

 

 

 

Respondents' eligibility confirmed, but failed to complete the interview

2,933

29.7%

Household-level refusal

8

0.1%

Known respondent refusal

5

0.1%

Appointment date beyond the end of the fieldwork period

2,874

29.1%

Partial interview

9

0.1%

Miscellaneous

37

0.4%

 

 

 

Successful cases

503

5.1%

 

 

 

Total

9,879

100.0%