ORANGE COUNTY ANNUAL SURVEY 1994

Survey Methodology

The Orange County Annual Survey, UCI was co-directed by Mark Baldassare, professor and chair of urban and 
regional planning, and Cheryl Katz, research associate. The random telephone survey included interviews 
with 1,000 Orange County adult residents conducted August 19 to 29, 1994. 

Interviewing was conducted on weekend days and weekday nights, using a computer-generated random sample 
of telephone numbers. Within a household, adult respondents were randomly chosen for interview. Each 
interview included 94 questions and took an average of 20 minutes to complete. The interviewing was 
conducted in English and Spanish, as needed.

The completion rate for the survey was 61 percent. This rate is consistent with earlier Orange County 
Annual Surveys. Of the telephone numbers called, 20 percent resulted in completed interviews and 13 
percent were refusals. The field work was conducted by Interviewing Services of America of Van Nuys, CA.

The sample was compared to the 1990 U.S. Census population figures by city for Orange County and was 
found to represent the actual regional distribution of Orange County residents. The sample's demographic 
characteristics were also closely comparable to the Census and other data available on Orange County 
residents.

The sampling error for this survey is +/- 3 percent at the 95 percent confidence level. This means that 
95 times out of 100, the results will be within 3 percentage points of what they would be if all adults 
in Orange County were interviewed. The sampling error for any subgroup would be larger. Sampling error is 
just one type of error to which surveys are subject. Results may also be affected by question wording, 
ordering, and survey timing.