Accuracy Assessment FAQ Metadata
Frequently-anticipated questions:
- Title: Rock Creek Park Vegetation Mapping Project - Accuracy Assessment Points
- Abstract:
-
The accuracy assessment field work was performed
in 1998 to verify the accuracy of the
vegetation communities spatial data developed by
the USGS-NPS Vegetation Mapping Program for Rock
Creek Park. The data points were randomly chosen
using ArcView random sampling routine according to
vegetation association over the project area
according to protocols developed by the Program.
Points were located by GPS navigation and the
community information was collected at the point,
without knowledge of the attributes of the
vegetation spatial data.
- How should this data set be cited?
U.S. Geological Survey, and Department of the Interior, 1998, Rock Creek Park Accuracy Assessment: USGS-NPS Vegetation Mapping Program Rock Creek Park, USGS Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.
Online Links:
- What geographic area does the data set cover?
- West_Bounding_Coordinate: 77.1
- East_Bounding_Coordinate: 77
- North_Bounding_Coordinate: 38.98333
- South_Bounding_Coordinate: 38.9
- Description_of_Geographic_Extent: Rock Creek Park, Washington D.C. and environs.
- What does it look like?
- <http://biology.usgs.gov/npsveg/rocr/images/rocraa.pdf> (PDF)
-
225 kbyte file showing vegetation associations and
location of accuracy assessment points
- Does the data set describe conditions during a particular time period?
- Calendar_Date: 1998
- Currentness_Reference: Source of data collection
- What is the general form of this data set?
- Geospatial_Data_Presentation_Form: database and report
- How does the data set represent geographic features?
- How are geographic features stored in the data set?
- Indirect_Spatial_Reference:
-
The ecology field sites were digitized to indicate
the area for which a TNC ecologist conducted an
ecological field sampling.
This is a Point data set.
It contains the following vector data types (SDTS terminology):
- What coordinate system is used to represent geographic features?
- Grid_Coordinate_System_Name: Universal Transverse Mercator
- Universal_Transverse_Mercator:
-
- UTM_Zone_Number: 18
- Transverse_Mercator:
-
- Longitude_of_Central_Meridian: -180
- Latitude_of_Projection_Origin: -90
- False_Easting: 50000
- False_Northing: 0
- Scale_Factor_at_Central_Meridian: 0.9996
Planar coordinates are encoded using coordinate pair
Abscissae (x-coordinates) are specified to the nearest 1
Ordinates (y-coordinates) are specified to the nearest 1
Planar coordinates are specified in Meters
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is Geodedic Reference System 80.
The semi-major axis of the ellipsoid used is 6378137.
The flattening of the ellipsoid used is 1/298.257.
- Vertical_Coordinate_System_Definition:
-
- Altitude_System_Definition:
-
- Altitude_Datum_Name: North American Vertical Datum of 1988
- Altitude_Resolution: 1
- Altitude_Distance_Units: Feet
- Altitude_Encoding_Method:
-
Explicit elevation coordinate included with horizontal coordinates
- How does the data set describe geographic features?
- Entity_and_Attribute_Overview:
-
The National Vegetation Classification Standard is
organized hierarchically to support conservation
and resource stewardship applications across
multiple scales. The upper levels of the hierarchy
are based on the physical form or structure of the
vegetation (physiognomy) and have been refined
from the international standards developed by the
United nations Educational, Scientific, and
Cultural Organization (UNESCO). The two most
detailed levels of the hierarchy are based on the
species composition of existing vegetation
(floristics) and reflect the phyto-sociological
standards that were originally developed by
European ecologists. The vegetation classification
is continually advanced through the collection and
analysis of new field data and will be greatly
strengthened during the course of the USGS-NPS
mapping efforts. Data file attributes include
species, alliance, community element, and land cover.
- Entity_and_Attribute_Detail_Citation:
-
Grossman, D. Et al. 1994. National Park Service/
National Biological Service Vegetation Mapping
Project, Standardized National Vegetation
Classification System 209 pp.
- What biological taxa does this data set concern?
- Taxonomy:
-
- Keywords/Taxon:
-
- Taxonomic_Keyword_Thesaurus: None
- Taxonomic_Keywords: National Vegetation Classification System
- Taxonomic_System:
-
- Classification_System/Authority:
-
- Classification_System_Citation:
-
- Citation_Information:
-
- Originator:
-
United States Department of the Interior Core
Science Systems and National Park Service
- Publication_Date: 19941101
- Title:
-
Standardized National Vegetation Classification
System
- Edition: Version 1
- Geospatial_Data_Presentation_Form: Classification System
- Series_Information:
-
- Series_Name: USGS/NPS Vegetation Mapping Program
- Issue_Identification: Final Draft
- Publication_Information:
-
- Publication_Place: Redlands, California
- Publisher: ESRI
- Other_Citation_Details: Prepared by the Nature Conservancy
- Identification_Reference:
-
- Citation_Information:
-
- Originator:
-
United States Department of the Interior Core
Science Systems and National Park Service
- Publication_Date: 19941101
- Title:
-
Standardized National Vegetation Classification
System
- Edition: Version 1
- Geospatial_Data_Presentation_Form: Classification System
- Series_Information:
-
- Series_Name: USGS/NPS Vegetation Mapping Program
- Issue_Identification: Final Draft
- Publication_Information:
-
- Publication_Place: Redlands, California
- Publisher: ESRI
- Other_Citation_Details: Prepared by the Nature Conservancy
- Taxonomic_Procedures:
-
See "Photo Interpretation Report, CSS/NPS Vegetation and Inventory and Mapping Program,
Rock Creek Park," October 1, 1998 <http://biology.usgs.gov/npsveg/rocr/rocrpirpt.pdf>
- Taxonomic_Completeness: Complete
- General_Taxonomic_Coverage:
-
Vegetation Alliances of the National Vegetation
Classification System (October 1995)
- Taxonomic_Classification:
-
- Taxon_Rank_Name: Kingdom
- Taxon_Rank_Value: Plantae
- Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
- U.S. Geological Survey
- Department of the Interior
- Who also contributed to the data set?
- To whom should users address questions about the data?
USGS/CSS/Core Science Analytics and Synthesis
c/o USGS-NPS Vegetation Mapping Program Coordinator
Denver Federal Center, Building 810, Room 8000, MS 302
Denver, Colorado 80225
(303) 202-4220 (voice)
303-202-4219 (FAX)
gs-b-npsveg@usgs.gov
To verify the accuracy of the mapped vegetation
communities at Rock Creek Park.
- What methods were used to collect the data?
- Method 0 of 2
-
Type: Field
Data points were located by use of a PLGR GPS
receiver. Vegetation communities were identified
on the basis of a dichotomous field key and plant
species present.
- Method 0 of 2
-
Type: Lab
Accuracy assessment points were compiled into an
ARCINFO point coverage and intersected with the
vegetation community coverage. The resulting INFO
file was exported into a text file, imported into
a spreadsheet, and the attributes from the
accuracy assessment and the spatial data were
compared. If the attributes did not compare, an
analysis of the mismatch was made and either the
AA attribute or the map attribute was changed
based on identification of the community on the
aerial photo.
- From what previous works were the data drawn?
- Accuracy Assessment Procedures Document (source 1 of 2)
-
U.S. Geological Survey - Core Science Systems, U.S. National Park Service, and Department of the Interior, 199411, Accuracy Assessment Procedures, USGS/NPS Vegetation Mapping Program: USGS, Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.
- Other_Citation_Details:
-
Prepared by: Aerial Information Systems; Redlands, CA and
The Nature Conservancy, Arlington, VA under contract from
U.S. Geological Survey Core Science Systems and
National Park Service.
- Type_of_Source_Media: electronic document
- Source_Contribution:
-
This document established the procedures and protocols for the accuracy assessment
at Rock Creek Park.
- Spatial data of vegetation communities for Rock Creek Park. (source 2 of 2)
-
U.S. Geological Survey, and Department of the Interior, 19961029, Rock Creek Park Spatial Vegetation Data: Cover type / Association level of the National Vegetation Classification System: USGS-NPS Vegetation Mapping Program Rock Creek Park, USGS, Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.
- Other_Citation_Details:
-
Created in large part by Aerial Information Systems
Redlands, CA under contract rom USGS/CSS/CSAS.
- Type_of_Source_Media: Disc
- Source_Contribution:
-
The vegetation spatial data were tested for
accuracy with the AA data.
- How were the data generated, processed, and modified?
- Date: 1998 (process 1 of 1)
-
The accuracy assessment field work was performed
in 1998 to verify the accuracy of the vegetation
communities spatial data developed by the
USGS-NPS Vegetation Mapping Program for Rock
Creek Park. The data points were randomly
chosen using ArcView random sampling routine
according to vegetation association over the project
area according to protocols developed by the Program.
Points were located by GPS navigation and the
community information was collected at the point,
without knowledge of the attributes of the
vegetation spatial data.
Data sources used in this process:
- Spatial data of vegetation communities for Rock Creek Park.
- Accuracy Assessment Procedure Document
- What similar or related data should the user be aware of?
- How well have the observations been checked?
The attributes for the accuracy assessment were
recorded in the field in 1998. Vegetation
associations were identified based on the field
key and plant identification. If additional
communities were found within a 50 meter radius of
the plot center, they were recorded as well
- How accurate are the geographic locations?
X,Y UTM coordinates representing each of the 265 plots were collected by
P-code PLGR (Precise Lightweight GPS Receiver) receivers, with an
accuracy ranging from +/- 10 m. to +/- 30 m. based on 60 second
averaging at each point.
- How accurate are the heights or depths?
Not applicable
- Where are the gaps in the data? What is missing?
All points were collected and analyzed. Several
points fell outside the mapping area, so were
discarded.
- How consistent are the relationships among the observations, including topology?
All attributes are codes that correspond to
vegetation communities and have been checked for
topographical and logical errors.
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
-
Any person using the information presented here
should fully understand the data collection and
compilation procedures, as described in these
metadata, before beginning analysis. The burden
for determining fitness for use lies entirely
with the user. For purposes of publication or
dissemination, citation or credit should be given
to the U.S. Geological Survey and the National
Park Service.
- Who distributes the data set? (Distributor 1 of 1)
USGS/CSS/Core Science Analytics and Synthesis
c/o USGS-NPS Vegetation Mapping Program Coordinator
Denver Federal Center, Building 810, Room 8000, MS 302
Denver, Colorado 80225
(303) 202-4220 (voice)
303-202-4219 (FAX)
gs-b-npsveg@usgs.gov
- What's the catalog number I need to order this data set?
- What legal disclaimers am I supposed to read?
The U.S. Geological Survey and the National Park Service shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics (if available) are not legal documents and are not intended to be used as such.
The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. Any related graphics (if available) are intended to aid the data user in acquiring relevant data; it is not approriate to use the related graphics as data.
The U.S. Geological Survey and the National Park Service gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from an U.S. Geological Survey and National Park Service servers and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. Mention of trade names or commercial products in this metadata report does not constitute endorsement or recommendation for use by the U. S. Department of the Interior, U. S. Geological Survey and National Park Service.
- How can I download or order the data?
- Availability in digital form:
- Cost to order the data: None
- Dates:
- Last modified: Feb-2001
Last Reviewed: 08-Jun-2010
- Metadata author:
-
USGS/CSS/Core Science Analytics and Synthesis
c/o USGS-NPS Vegetation Mapping Program Coordinator
Denver Federal Center, Building 810, Room 8000, MS 302
Denver, Colorado 80225
(303) 202-4220 (voice)
303-202-4219 (FAX)
gs-b-npsveg@usgs.gov
- Metadata standard:
- FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata (FGDC-STD-001.1-1999)
- Metadata extensions used:
-
Generated by mp version 2.9.12 on Tue Jun 08 11:15:16 2010
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