Labor Force Data Derived from the Current Population Survey
http://www.bls.gov/opub/hom/homch1_g.htm Each month, during the calendar week containing the 19th day, interviewers contact a “responsible” person in each of the sample households in the CPS. At the time of the first enumeration of a household, the interviewer visits the household and prepares a roster of the household members, including their personal characteristics (date of birth, sex, race, ethnic origin, marital status, educational attainment, veteran status, and so on) and their relationship to the person maintaining the household. The interviewers enter this information into laptop computers. This roster is then checked for accuracy and brought up to date at each subsequent interview to take account of new or departed residents, changes in marital status, and similar items. The information on personal characteristics is thus available each month for identification purposes and for cross-classification with economic characteristics of the sample population.
Personal visits are preferred in the first month in which the household is in the sample. In other months, the interview generally is conducted by telephone. Approximately 70 percent of the households in any given month are interviewed by telephone. A portion of the households (10 percent) is interviewed via computer-assisted telephone interviewing (CATI), from three centralized telephone centers (located in Hagerstown, MD; Jeffersonville, IN; and Tucson, AZ) by interviewers who also use a computerized questionnaire.
At each monthly visit, a series of standard questions on labor market activity during the preceding week is asked about each household member 15 years of age and older. (As previously mentioned, the official labor force estimates pertain to those aged 16 and older.) The primary purpose of these questions is to classify the sample population into the three basic economic groups: The employed, the unemployed, and those not in the labor force.
At the end of each day’s interviewing, the data collected are transmitted to the Census Bureau’s central computer in Washington, DC. Once files are transmitted to the main computer, they are deleted from the laptops.
Because of the crucial role interviewers have in the household survey, a great amount of time and effort is spent maintaining the quality of their work. Interviewers are given intensive training, including classroom lectures, discussion, practice, observation, home-study materials, and on-the-job training. At least once a year, they convene for daylong training and review sessions, and, also at least once a year, they are accompanied by a supervisor during a full day of interviewing to determine how well they carry out their assignments.
A selected number of households are reinterviewed each month to determine whether the information obtained in the first interview was correct. The information gained from these interviews is used to improve the entire training program.