Supporting Statement 2700-0113 - B

SUPPORTING STATEMENT

2700- 0113

B. Collections of Information Employing Statistical Methods.

1. Describe (including a numerical estimate) the potential respondent universe and any sampling or other respondent selection methods to be used. Data on the number of entities in the universe covered by the collection and in the corresponding sample are to be provided in tabular form for the universe as a whole and for each of the strata in the proposed sample. Indicate expected response rates for the collection as a whole. If the collection had been conducted previously, include the actual response rate achieved during the last collection.

The potential respondent universe is the total current population of the U.S. There are, according to the 2000 Census, 104.7 million households forming the universe. The research sample will be purchased from one of the many firms specializing in extracting records from the government census data, such as American Business Information, Donnelley Marketing/American Consumer Lists, Hugo Dunhill Mailing Lists, Experian, and Scientific Telephone Samples. The lists can be purchased as Random Digit Dial samples, using any one of the standard sampling methodological selection methods,: Type A (EPSEM), Type B (weighted) Cluster, Mitofsky Waksberg, or Sudman.

Refusal rates for marketing research studies typically run between 20%-30% depending on the nature and timing of the project. Thus, expected response rates are between 70%-80%.

2. Describe the procedures for the collection of information including:

• Statistical methodology for stratification and sample selection,

• Estimation procedure,

• Degree of accuracy needed for the purpose described in the justification,

• Unusual problems requiring specialized sampling procedures, and

• Any use of periodic (less frequent than annual) data collection cycles to reduce burden.

RDD samples are constructed using one of two different methodologies for pulling working blocks, either Type A (EPSEM/pure4/unweighted) or Type B (weighted/efficient).

Type A samples are pulled using a strict definition of randomness. They are called unweighted samples because each possible telephone number within appropriate blocks has an equal chance of being selected to generate a random digit number.

Type B samples are pre-weighted so RDD numbers are created from telephone working blocks in proportion to the estimated number of household listings in each working block.

Lists include name, addresses, and phone numbers for each household, along with other specific demographic information which may be relevant to monitor the structure of the sample compared to substrata of the universe.

The standard degree of confidence set for statistical accuracy in marketing research is the .90 level. However, often we apply higher standards where more sensitive issues are concerned, moving to the .95 confidence level.

3. Describe methods to maximize response rates and to deal with issues of non-response. The accuracy and reliability of information collected must be shown to be adequate for intended uses. For collections based on sampling, a special justification must be provided for any collection that will not yield “reliable” data that can be generalized to the universe studied.

Respondents are immediately told that the call is for a national market research study on current social issues in our society, that they will remain anonymous and not be held accountable for their views. They are also told their opinions may represent thousands of other people like themselves, and are important for us to hear so that they may be included in the study. They are assured that they are not being solicited to try or use any product or service.

Calls are made from a central phone bank. Calling is computerized, so that all contacts are automatically verified and classified. Additionally, supervisory personal are auditing the calls for validation and other aspects of quality control.

Contact with unwilling respondents are quickly and politely terminated, and substitution is made following the random selection procedure.

4. Describe any tests or procedures or methods to be undertaken. Testing is encouraged as an effective means of refining collections of information to minimize burden and improve utility. Tests must be approved if they call for answers to identical questions from 10 or more respondents. A proposed test or set of tests may be submitted for approval separately or in combination with the main collection of information.

Initial interviews are reviewed to insure that the research is producing the type of responses intended. In other words, they are examined to be certain that questions are being understood by respondents, and answered in a complete and satisfactory manner.

The computerized administration of the interview insures that all appropriate questions are asked, and that any skip patterns are followed. Along with the computerized approach, standard interviewer training and briefing insures that administration is consistent from interview to interview.

Any interview found for any reason not to be completed to standards will be replaced with an interview among a respondent with identical demographic characteristics.

5. Provide the name and telephone number of individuals consulted on statistical aspects of the design and the name of the agency unit, contractor(s), grantee(s), or other person(s) who will actually collect and/or analyze the information for the agency.

Larry Percy, 334-265-0094

Martin Buncher (IMI Inc.), 858-756-1765

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