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pdfSUPPORTING STATEMENT FOR REQUEST FOR OMB APPROVAL
UNDER THE PAPERWORK REDUCTION ACT
PART B –
COLLECTION OF INFORMATION EMPLOYING STATISTICAL METHODS
1. Description of Universe and Selection Methods Used
As described in Part A of the Supporting Statement, the data validation methodology
consists of two parts:
1) Report validation evaluates the validity of aggregate reports submitted to ETA by
53 states or territories. It does so by checking the accuracy of the state’s reporting
software used to calculate the reports. The universe for report validation comprises
all participant records included in the extract file. Report validation is accomplished
by independently processing an entire file of participant records, providing validation
counts, and comparing the validation counts to those reported by the state or grantee.
2) Data element validation assesses the accuracy of participant data records. For
Workforce Investment Act (WIA) Title IB, the universe for data element validation
comprises records of participants who exited between April 1st of the year prior to the
program year through March 31st of the current program year. For Wagner-Peyser,
the universe for data element validation is comprised of participants who have been
placed and retained in employment. For Trade Adjustment Assistance (TAA), the
universe for data element validation comprises all Trade Act participant records
submitted to ETA during the prior fiscal year. For the National Farmworker Jobs
Program (NFJP), the universe for data element validation comprises all NFJP records
submitted to ETA during the prior program year. Data element validation is
performed by reviewing samples of participant records against source documentation
to ensure compliance with federal definitions.
The data validation process results in an estimate of the error rates for each data element
and each reported count. Error rates are estimated separately for each state or grantee for
the WIA, TAA, and NFJP programs. Error rates cannot be estimated for Wagner-Peyser
because statistically valid samples are not used.
The methodology for data element validation employs sampling to improve the efficiency
of the validation process. To minimize states’ and grantees’ burden in performing
validation consistent with producing a reliable estimate of the error rates, the data
element validation process is designed to compute a reliable error rate using the smallest
possible sample size. To accomplish these objectives, three sampling techniques are
used:
•
Variable sampling rates among states are used to reduce the burden on small
states and grantees as much as possible.
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•
Oversampling high-risk and high-importance cases is used to provide a more
accurate estimate of the error rate.
•
For WIA Title IB and TAA programs, multistage sampling is employed. Samples
of offices are selected, and records are selected for validation only within sampled
offices. This multistage design reduces the number of locations that state staff
must visit to access supporting documentation.
These sampling methods balance the numbers of records and the numbers of locations so
that the overall burden is reduced as much as possible, while still achieving a reliable
estimate of error.
To reduce the burden on states and grantees, ETA provides validation software that
calculates the validation values, imports the reported counts, draws the data element
validation samples, produces online and paper validation worksheets, calculates error
rates, and produces the validation reports.
Data validation relies on existing records from state and grantee management information
systems and case files. Response rate issues do not arise in the data validation program.
2. Procedures for the Collection of Information
A. Statistical Methodology for Stratification and Sample Selection
•
Item B.1 above indicates that report validation does not require states to use
samples.
•
For data element validation, multistage samples of participant records will be
drawn. Independent samples are selected in each state for 7 groups – TAA, NFJP,
and 5 WIA groups (dislocated workers, NEGs, adults, older youth, and younger
youth). For TAA and NFJP, stratification is not employed within the samples
either in the selection of offices or records. Stratification would not add
substantially to the accuracy of error rate estimates. For WIA, stratification of
offices is employed to reduce the burden of validation. Offices are stratified
based upon the distribution of records of dislocated workers, NEGs, adults, older
youth, and younger youth.
•
To increase the efficiency of the process, records receive a risk weight of 1, 2, or
3 based upon two factors: whether the record is a success for calculating
performance (i.e., whether the adult, dislocated worker, NEG, older youth, TAA
participant, or NFJP participant was employed in the first quarter after exit or the
younger youth received a diploma within one quarter after exit), and the risk that
the data used to calculate performance are in error. In addition, WIA records
receive a density weight that equals the number of elements to be validated per
record. The two weights are added to determine a composite weight. The
composite weights result in oversampling records that are more likely to contain
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errors and are judged to be more substantively important (i.e., an error in such a
record would be more important for a state or grantee).
•
For WIA title IB programs, offices are selected at the first stage for the data
element validation. Each office is assigned a weight equal to the sum of the
weights for the individual records associated with that office. For each state’s
WIA validation, offices are stratified. Up to 5 strata may be created. The strata
are based upon the number of offices in the state, the weight of each office, and
the distribution of records across the 5 WIA groups. Up to 15 offices may be
selected per stratum, leading to a maximum of 75 offices sampled for the state.
•
For TAA programs, offices are selected at the first stage for the data element
validation. Each office is assigned a weight equal to the sum of weights for the
individual records associated with that office. For each state’s TAA validation, a
sample of offices is then selected using probability proportional to size (PPS)
methods. The selection probability of an office is based upon the total number of
offices in the state and the weight of that office. Samples of records are then
drawn from within the selected offices. Each record has a probability of selection
proportional to its weight. The expected number of offices selected in a state is
based on the total number of offices shown in Table A.
•
For NFJP, no offices are sampled. Records are sampled directly. Each record has
a probability of selection proportional to its weight.
Table A
TAA OFFICE SAMPLING
1
2
3
4
5
6
7
Number of Offices in
State (N)
A
250 or more
200-249
100-199
75-99
30-74
7-29
Fewer than 7
Number of Offices
Sampled (n)
B
30
25
20
15
10
7
All
To reduce the relative burden on small states and grantees, their samples are smaller.
After standards are established, it is reasonable to implement a design that holds
smaller states to a lower standard of precision (hence, a smaller sample) because
smaller states have fewer resources to devote to validation and they have a smaller
impact upon national performance. The sample sizes are set so that the samples
drawn have a maximum 95 percent confidence interval of +/- 3.5 percentage points
for larger states and grantees and +/- 4 percentage points for smaller states and
grantees, given certain assumptions. These assumptions are that the error rate is 5.0
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percent and that the use of multistage sample selection and unequal sampling rates
will result in a design effect of 2.0; that is, they will increase the variance of sample
estimates by a factor of 2.0 compared to the variance of simple random samples of the
same size. Where a substantial proportion of the universe of records will be sampled,
allowances are also made for the finite population correction. Tables B and C show
the ranges of overall sample sizes for states for WIA and TAA. Table D shows the
ranges of overall sample sizes for NFJP grantees.
Table B
WIA EXITER RECORD SAMPLING
A
B
C
# of Exiters
Half-Length of the
Confidence Interval
Range of Sample
Size
1
500 or greater
3.5%
187-350
2
0-499
4%
0-187
Table C
TAA EXITER RECORD SAMPLING
A
B
C
# of Exiters
Half-Length of the
Confidence Interval
Range of Sample
Size
1
300 or greater
3.5%
100-180
2
0-299
4%
0-113
Table D
NFJP EXITER RECORD SAMPLING
A
B
C
# of Exiters
Half-Length of the
Confidence Interval
Range of Sample
Size
1
300 or greater
3.5%
100-150
2
0-299
4%
0-83
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B. Estimation Procedure
For report validation, the states and grantees compare their annual reported values to
the validation values to determine if the error rate is within an acceptable range. In
the future, ETA will set standards for acceptable error rates for report validation.
For data element validation, estimation will include computing sample weights and
estimates of error rates. Validators compare the data from the samples to source
documentation. Once all the data have been evaluated, error rates are calculated for
each data element. These error rates are estimated using data weighted to account for
differences in probability of selection. During the initial year, states will not produce
estimates of the precision of estimated error rates. In later years, after standards for
the states have been established, precision estimates will be used to evaluate whether
the sample error rate estimates indicate that a state has failed to meet the established
standards. The validation software computes the sampling errors for each state or
grantee, taking into account the multistage design and the use of unequal weights.
C. Degree of Accuracy Needed for Purpose Described in the Justification
For data validation to be effective and to allow for continuous improvement, ETA is
establishing acceptable levels for the accuracy of reports and data elements in phases.
Error rates for report validation and data element validation will be established
independently of one another based on the analysis of validation efforts currently
underway. For report validation, the first three validation years focused on detecting and
resolving any issues with state and grantee data and reporting systems. Error rates
collected in these years will be analyzed and, based on this information, standards for
accuracy will be established for the Program Year (PY) 2007 report validation. The
implementation of a set of common performance measures has delayed the establishment
of standards for data element validation until states have had at least two years to validate
the same data elements. Once accuracy standards are established, states and grantees will
be held accountable for meeting those standards and will be required to address any
issues concerning data accuracy.
D. Unusual Problems Requiring Specialized Sampling Procedures
The discussion above indicates that the methodology uses specialized sampling
procedures. Strictly speaking, none of these are required. By using sampling techniques,
however, the burden that data element validation imposes upon the states and grantees is
significantly reduced.
3. Response Rates
As mentioned in Part 1, response rate issues do not arise in the data validation program.
Data validation relies on existing records from state and grantee management information
systems and case files. Through the use of valid sampling techniques, the validation
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process results in estimates of data accuracy that can be generalized to the universe of
data reported to ETA on program performance and activities.
4. Tests of Procedures or Methods
WIA Title IB, Wagner-Peyser, and TAA program staff have been conducting data
validation for three years; the NFJP has been conducting validation for two years. The
states and grantees received training prior to beginning validation and receive ongoing
training and technical assistance from ETA’s data validation contractor throughout the
validation process. Results of these data validation activities indicate that the
methodology has functioned as intended and has enabled states to identify and address
reporting errors.
5. Individuals Consulted on Statistical Aspects of the Design
William S. Borden
Senior Fellow
Mathematica Policy Research, Inc.
(609) 275-2321
Donsig Jang
Senior Statistician
Mathematica Policy Research, Inc.
(202) 484-4246
John Eltinge
Assistant Commissioner
for Survey Method Research
Bureau of Labor Statistics
U.S. Department of Labor
(202) 691-7404
Jonathan Ladinsky
Senior Program Analyst
Mathematica Policy Research, Inc.
(609) 275-2250
John Hall
Senior Sampling Statistician
Mathematica Policy Research, Inc.
(609) 799-3535
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File Type | application/pdf |
File Title | Microsoft Word - 1. DV OMB TOC_050707.doc |
Author | TArmington |
File Modified | 2007-11-16 |
File Created | 2007-11-16 |