Introduction
| Metadata
| Acquisition
Dates | Accuracy Assessments | FAQ
| Vendor
Links
ADOP Accuracy Assessments
The Arkansas Geographic Information Office is responsible
for reviewing all of the digital ortho quarter quadrangle
(DOQQ) files delivered to the state through the ADOP
project. The review process includes a visual quality
analysis, a visual comparison between the first and
second generation DOQQ's, a visual check for edgematch
consistency, and when time permits, a horizontal accuracy
assessment. Accuracy assessments are performed following
the National
Standard for Spatial Data Accuracy (NSSDA).
All accuracy assessments that are performed by the State
Geographic Information Office will be posted to this
web page.
Utilizing the NSSDA
The Federal
Geographic Data Committee (FGDC) established the
NSSDA in 1998. The NSSDA provides a "statistical testing"
methodology for reporting the horizontal and vertical
accuracy of vector and raster graphics. These methodologies
enable one to compare the coordinates of an independent
data set to the coordinates of the test data set to
determine the horizontal or vertical accuracy of the
test data set. The document below will examine the horizontal
accuracy of a second-generation digital orthophoto quarter
quadrangle (DOQQ) produced by Pixxures. The independent
data set was created utilizing GPS methodologies and
the Arkansas Mapping Grade GPS Standard. The test data
set was created by heads-up digitizing points on the
second-generation DOQQ. Reporting the accuracy of spatial
data following a common methodology allows end-users
of the spatial data to determine its usefulness.
Note: DOQQ's produced in the same project may
have different accuracies, regardless of the project
parameters. The elevation model, control points and
other components of the DOQQ process contribute to its
accuracy. Each DOQQ should be tested independently when
its known accuracy is required.
Accuracy Assessment Reports
Refer to the Horizontal Accuracy Worksheet Results
(located in the appendix of each report) to determine
the exact horizontal accuracy. Findings have been rounded
to the nearest meter in the results reported below.
For example, Hope SW tested 5.49219054 m or 18.01895998
feet, which was rounded to 5 m or 18 feet.
Ashley
County Mosaic - The Ashley County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Benton
County Mosaic - The Benton County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 4 meters (13 feet) horizontal accuracy
at a 95% confidence level.
Bradley
County Mosaic - The Bradley County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Chicot
County Mosaic - The Chicot County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 3 meters (10 feet) horizontal accuracy
at a 95% confidence level.
Clark
County Mosaic - The Clark County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Clay
County Mosaic - The Clay County Mosaic created with
the second generation DOQQ's utilizing Mr. SID Encoder
tested 4 meters (13 feet) horizontal accuracy at a 95%
confidence level.
Columbia
County Mosaic - The Columbia County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 7 meters (23 feet) horizontal accuracy
at a 95% confidence level.
Conway
County Mosaic - The Conway County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 6 meters (20 feet) horizontal accuracy
at a 95% confidence level.
Crawford
County Mosaic - The Crawford County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 8 meters (26 feet) horizontal accuracy
at a 95% confidence level.
Grant
County Mosaic - The Grant County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 4 meters (13 feet) horizontal accuracy
at a 95% confidence level.
Greene
County Mosaic - The Greene County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Hempstead
County Mosaic - The Hempstead County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 8 meters (26 feet) horizontal accuracy
at a 95% confidence level.
Jefferson
County Mosaic - The Jefferson County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Johnson
County Mosaic - The Saline County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 10 meters (33 feet) horizontal accuracy
at a 95% confidence level.
Lafayette
County Mosaic - The Lafayette County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Miller
County Mosaic - The Miller County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 9 meters (30 feet) horizontal accuracy
at a 95% confidence level.
Montgomery
County Mosaic - The Montgomery County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 7 meters (23 feet) horizontal accuracy
at a 95% confidence level.
Nevada
County Mosaic - The Nevada County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Pike
County Mosaic - The Pike County Mosaic created with
the second generation DOQQ's utilizing Mr. SID Encoder
tested 6 meters (20 feet) horizontal accuracy at a 95%
confidence level.
Polk
County Mosaic - The Polk County Mosaic created with
the second generation DOQQ's utilizing Mr. SID Encoder
tested 8 meters (26 feet) horizontal accuracy at a 95%
confidence level.
Prairie
County Mosaic - The Prairie County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (13 feet) horizontal accuracy
at a 95% confidence level
Pulaski
County Mosaic - The Pulaski County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 5 meters (16 feet) horizontal accuracy
at a 95% confidence level.
Pulaski
County DigitalGlobe Geotiffs - The Pulaski County
DigitalGlobe Geotiffs tested 4 meters (12 feet) horizontal
accuracy at a 95% confidence level.
Saline
County Mosaic - The Saline County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 8 meters (24 feet) horizontal accuracy
at a 95% confidence level.
Scott
County Mosaic - The Scott County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 9 meters (30 feet) horizontal accuracy
at a 95% confidence level.
Sebastian
County Mosaic - The Sebastian County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 9 meters (30 feet) horizontal accuracy
at a 95% confidence level.
Stone
County Mosaic - The Sebastian County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 10 meters (33 feet) horizontal accuracy
at a 95% confidence level.
White
County Mosaic - The White County Mosaic created
with the second generation DOQQ's utilizing Mr. SID
Encoder tested 4 meters (13-feet) horizontal accuracy
at 95% confidence level
Van
Buren County Mosaic - The Van Buren County Mosaic
created with the second generation DOQQ's utilizing
Mr. SID Encoder tested 9-meters (30-feet) horizontal
accuracy at 95% confidence level.
Yell
County Mosaic - The Yell County Mosaic created with
the second generation DOQQ's utilizing Mr. SID Encoder
tested 7-meters (23-feet) horizontal accuracy at 95%
confidence level.
Digital Ortho Quarter Quad NSSDA Test
Mandeville
Southwest - The Mandeville SW second generation
DOQQ tested 5-meters (16-feet) horizontal accuracy at
95% confidence level.
Warren
Northwest - The Warren NW second generation DOQQ
tested 5-meters (16-feet) horizontal accuracy at 95%
confidence level.
Hope
Southwest- The Hope SW second generation DOQQ tested
5-meters (16-feet) horizontal accuracy at 95% confidence
level.
NOTE: These documents
are in Acrobat Reader format.
If you do not have Acrobat Reader 5.0 loaded on your
computer, you must first install it in order to
view or print a PDF documents.
Introduction
| Metadata
| Acquisition
Dates | Accuracy Assessments | FAQ
| Vendor
Links
|
