0256 - Feral Swine Surveys - SSB - Nov 2016

Supporting Statement – Part B

FERAL SWINE SURVEY

OMB No. 0535-0256

B. COLLECTION OF INFORMATION EMPLOYING STATISTICAL METHODS

1. Describe (including a numerical estimate) the potential respondent universe and any sampling or other respondent selection method to be used. Data on the number of entities (e.g., establishments, State and local government units, households, or persons) 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 has been conducted previously, include the actual response rate achieved during the last collection.

The 2017 Feral Swine Damage to Livestock Survey Sampling Frame comprises NASS List Frame operations that raise cattle, hogs, sheep and/or goats in the following 13 States: Alabama, Arkansas, California, Florida, Georgia, Louisiana, Oklahoma, North Carolina, Mississippi, Missouri, South Carolina, Tennessee, and Texas.

The 2017 Feral Swine Damage to Livestock Sampling Frame was stratified by state, livestock type, and number of head. Means and standard deviations for each of the strata were inferred from corresponding strata on a related survey to generate strata level sample sizes.

The stratum level sample size formula is:

Where:

n_jh is the sample size for stratum h in state j,

N_jh is the population for stratum h in state j,

S_jh is the standard deviation for stratum h in state j,

CV_jh is the coefficient of variation for stratum h in state j, and

T_jh is the total for stratum h in state j

The sample size required to obtain national and state level CVs of eight percent and 10% to 12%, respectively, was rounded to 11,250.     

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

Questionnaires will be mailed around the middle of June, 2017. Operations that do not respond by mail or internet within a couple of weeks will be attempted by phone or personal enumeration. Responses will be monitored to make sure that the respondents are representative of the stratified sample. Extra efforts will be taken to collect data from any stratum that has insufficient coverage. After data collection is complete, the data will be edited for reasonableness and completeness.

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.

The survey will initially be mailed out to the entire sample. Respondents will be given the option to respond by either mail or internet. Non-respondents will be attempted by phone and there will be limited field enumerations for respondents who have been coordinated with any other surveys NASS will be conducting at that time. NASS will be using National Association of State Departments of Agriculture (NASDA) enumerators who have been working with NASS surveys for many years. Training will be provided by the NASDA supervisors and by our regional Data Collection Centers.

The USDA Animal and Plant Health Inspection Service (APHIS) has posted information to their website informing the public on: how to identify feral swine, the damages they cause, control methods that are available, government programs, and more. The public can access this information at:

https://www.aphis.usda.gov/aphis/ourfocus/wildlifedamage/operational-activities/feral-swine.

4. Describe any tests of procedures or methods to be undertaken.

NASS conducted six cognitive interviews prior to the beginning of data collection. An overview of the changes made to the questionnaire as a result of this testing is attached to this submission as a supplemental document. NASS will do internal testing of the edit and summary programs before any publications will be generated to insure accuracy of data.

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), or other person(s) who will actually collect and/or analyze the information for the agency.

The sample size for each State is determined by the Sampling and Frame Development Section, Methodology Division; Section Head is Peter Quan, (202) 720-5269.

Data collection is carried out by NASS Field Offices; Field Operation’s Director is Kevin Barnes (202) 720-8220.

The NASS Livestock Branch Chief is Dan Kerestes (202) 720-3570.

The NASS Survey Administrative Statistician in Headquarters for the Feral Swine Survey is Dawn Keen (202) 690-8804 in the Commodity Survey Section of the Survey Administration Branch, Census and Survey Division; Branch Chief is Gerald Tillman, (202) 720-3895. The Survey Administrator is responsible for coordination of sampling, questionnaires, data collection, training, Interviewers Manual, Survey Administration Manual, data processing, and other Field Office support.

The national summary is the responsibility of the Summary, Estimation and Disclosure Methodology Branch, Methodology Division; Branch Chief is Jeff Bailey (202) 720-4008.

November 2016