0052 SS 080411 Part B rev

SUPPORTING STATEMENT
MARINE RECREATIONAL INFORMATION PROGRAM
OMB CONTROL NO. 0648-0052

B. COLLECTIONS 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 governmental units, households, or persons)
in the universe and the corresponding sample are to be provided in tabular form. The
tabulation must also include expected response rates for the collection as a whole. If the
collection has been conducted before, provide the actual response rate achieved.
The sample universe is all saltwater anglers in the states of North Carolina, South Carolina,
Georgia and Florida. The survey utilizes a dual-frame approach to sample recreational, saltwater
anglers. The sample will be selected from state databases of licensed, saltwater anglers and
address frames (address-based sample or ABS) derived from the USPS Delivery Sequence File.
ABS sampling will utilize a two-phase approach to first screen households to identify saltwater
anglers and then collect information about recent saltwater fishing trips. The license frame
includes all anglers who have a saltwater fishing license in the study area during the reference
wave, and the 1st-phase ABS frame includes all residential addresses within the study area. The
2nd-phase ABS sample includes all saltwater anglers identified in the 1st-phase screening.
We select approximately 4,288 licensed anglers and 24,000 households each reference wave.
Frame Size
Sample Size

USPS DSF
19,259,1581
24,000

Complete Screeners

9,600 (40%)3

Eligible Anglers
Complete Angler Interviews

License Frame
1,700,0002
4,288

3,0964
1,704 (55%)5

2,040 (47.6%)6

1.

Estimated number of occupied households in the study area as of 7/1/2009.

2.

Approximate number of licensed saltwater anglers in the study area as of 1/1/2010

3.

Response rate based upon previous mail surveys of recreational saltwater anglers.

4.

Assumes 21.5% if responding households have eligible anglers and 1.5 anglers per eligible household.

5.

Previous studies have achieved 2nd-phase ABS response rates of 55-75%.

6.

Weighted average of expected mail (55%) and telephone (40%) response rates.

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2. Describe the procedures for the collection, including: the statistical methodology for
stratification and sample selection; the estimation procedure; the degree of accuracy
needed for the purpose described in the justification; any unusual problems requiring
specialized sampling procedures; and any use of periodic (less frequent than annual) data
collection cycles to reduce burden.
The survey collects recreational fishing effort data, including the number of shore and private
boat fishing trips, for independent, two-month reference waves.
The survey utilizes a dual-frame design that samples anglers from state databases of licensed
saltwater anglers (license frame) and residential address frames (address-based samples or ABS).
The union of the license and ABS frames consists of three domains: Households in the address
frame but not in the license frame, households in the license frame but not the address frame, and
households in both frames. If the address frame is complete, then the license frame is a subset of
the address frame, with the exception of licensed anglers who reside outside of the study area
(i.e. nonresident anglers).
Address Frame

The ABS frame is derived from the United States Postal Service, Delivery Sequence File (DSF)
and includes all residential addresses within the study area. Sampling is stratified by wave, state
and sub-state region, which is defined by geographic proximity to the coast.
Sampling from the ABS frame utilizes a three-phase design. In the first phase, random samples
of residential addresses are mailed a screening questionnaire designed to identify likely saltwater
anglers and collect telephone contact information. In the second phase, all adults who identify
themselves as saltwater anglers in the first phase are contacted by either telephone or mail and
asked to provide details about recreational saltwater fishing activity that occurred during the
reference wave. Second phase sample is randomly distributed among telephone and mail
treatments at the household level. In the third phase, all anglers who report an encounter with a
sea turtle are contacted by telephone and asked to provide details about the nature of the
encounter.
License Frame

Sampling from the license frame is stratified by wave, state (state of licensure) and sub-state
region of residence (coastal and non-coastal counties). License frame sampling includes an
additional stratum for licensed anglers who reside outside the state of licensure (nonresident
anglers).
The license frame is derived from state databases of all anglers who were licensed to participate
in saltwater fishing in the study states between the beginning of the wave and the time the
sample frame is created. Sampling from the license frame is conducted in two phases. In the
first phase, anglers are contacted and asked to provide details about fishing activity that occurred
during the reference wave. As with the ABS sample, license sample is randomly distributed
among telephone and mail treatments. In the second phase, all anglers who report an encounter
with a sea turtle are contacted by telephone and asked to provide details about the nature of the
encounter.
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Data are collected through either Computer Assisted Telephone Interviewing (CATI) or
completed and returned mail questionnaires. Regardless of data collection mode, data collection
is retrospective for the most recent two-month reference wave.
Estimation
As mentioned above, independent samples will be selected from the two frames to make direct
estimates of totals of the numbers of participants and fishing effort from each of the three
domains. Estimates of totals from the address frame will be produced for S1 and S12; while from
the license frame estimates will be produced for S2 and S12. The two totals for S12 will be
averaged to give a more precise overall estimate for S12. The three estimates will be summed to
estimate the total population.
The first step in estimation is to develop base weights that are the inverses of the probabilities of
selection for the units by frame. These standard weights will then be adjusted by the inverse of
the response rates within stratum, separately by frame, to account for nonresponse from within
each frame. Additional nonresponse weighting adjustment cells, defined by auxiliary
information included on the sample frames, will be examined in an effort to reduce potential
nonresponse error. The estimates produced from these weights will overestimate totals because
the units in the overlap are over-represented because they could be sampled from both frames.
The final step is to adjust the weights of the units in the overlap. A simple averaging of the two
overall domain estimates can be accomplished by dividing the weight of any unit in the overlap
by two. More sophisticated weighting schemes will also be examined.
The sample was designed to produce bi-monthly (wave), state-level estimates of total
recreational fishing effort with a percent standard error of no more than 10%. Sampling levels
will also satisfy the need to detect differences in survey variables between data collection mode
at the bi-monthly level.
3. Describe the methods used to maximize response rates and to deal with nonresponse.
The accuracy and reliability of the information collected must be shown to be adequate
for the intended uses. For collections based on sampling, a special justification must be
provided if they will not yield "reliable" data that can be generalized to the universe
studied.
For mail treatment groups, standard mail survey protocol will be implemented (Dillman et al,
2008). An initial mailing will include an introductory letter stating the purpose of the survey, a
screener questionnaire, a post-paid return envelope, and a $1.00 cash incentive. A thank
you/reminder postcard will be sent to all sample units one week following the initial mailing. A
final mailing, including a second questionnaire, a nonresponse conversion letter*, and a postpaid return envelope will be sent to all nonrespondents three weeks after the initial mailing.
*This is a letter which attempts to obtain a response from a person who has not yet responded.

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For telephone treatments, a minimum of 8 attempts will be made to contact each sample unit.
Contacts will be distributed among days and times to maximize the likelihood of completing
interviews.
In addition to implementing efforts to maximize response rates, we will also administer a
nonresponse follow-up study to contact nonrespondents from each frame for the first-phase
ABS screener and the angler questionnaires. The follow-up study, which will include
additional contact attempt using both telephone and email, will characterize the fishing activity
of nonrespondents. We will also examine alternative nonresponse weighting adjustment
strategies that utilize auxiliary information included on the sample frames to identify
adjustment cells.
4. Describe any tests of procedures or methods to be undertaken. Tests are encouraged as
effective means to refine collections, but if ten or more test respondents are involved
OMB must give prior approval.
No testing is planned.
5. Provide the name and telephone number of individuals consulted on the 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.
Statistical support was provided by the following:
Dr. J. Michael Brick, Westat, (301) 294-2004
Dr. Nancy A. Mathiowetz, University of Wisconsin-Milwaukee, (414) 229-2216

Rob Andrews, Fisheries Biologist, NOAA Fisheries Service, Office of Science and Technology,
(301) 427-8105 is the point-of-contact for the Agency.

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