The data set has an overall classification accuracy of 95%

	Producer’s	User’s
Agriculture	93.8	95.6
Forest	94.5	89.9
Grass	99.6	90.6
Urban	90.4	99.8
Water	91.7	97.5
Wetland	89.7	78.5

The reference data for 1991 were used to examine the field
and spectral response patterns of the corresponding 1998 TM
imagery to derive reference data for 1998 land cover classes.
Each area used for training signatures and accuracy assessment
for 1991 was checked against the 1998 TM imagery sets and
1997 DOQs to be certain that the general land cover class was
the same. Areas that had changed between the years were
discarded from the reference data if the 1998 cover type could
not be identified with certainty. Approximately 1.73% of the
total pixels, in 929 polygons, was available for training and
accuracy assessment with 76% used for training and 24% for
accuracy assessment.

Data provides coverage over the stated extent of the 7 county area. The original clip extent polygon used is no longer available.

RMS error is less than 1/4 - pixel or 7.5 meters

RMS error is less than 1/4 - pixel or 7.5 meters

Landsat Thematic Mapper multi-temporal imagery was classified over county-based areas using a supervised maximum likelihood classification within Erdas/Imagine software. A 3 by 3 majority filter was performed in post-processing step to remove the salt-and-pepper effect.

More information available from article "Land cover classification and change analysis of the Twin Cities (Minnesota)
Metropolitan Area by multitemporal Landsat remote sensing"
http://land.umn.edu/pubs.html

agriculture = tan
extraction = orange
forest = dark green
grass = light green
urban = white
water = blue
wetland = purple

Seven level one land cover classes are listed along with a detailed description below:

1. Urban/Developed -  

An area containing any amount of impervious cover of man-made solid materials or compacted soils including areas with interspersed vegetation.  Examples: parking lots, shopping malls, warehouses, industrail parks, highways, sparse development, single family residential developments, single lane roads, and mines.


2. Agriculture -

An area where the primary cover type during the growing season is an agricultural covertype including row crops, forage crops and small grains.  Examples: corn, soybeans, alfalfa, oats, wheat and barley.

3. Grassland - 

An upland area covered by cultivated or non-cultivated herbaceous vegetation predominated by grasses, grass-like plants and forbs.  Includes non-agricultural upland vegetation dominated by short manicured grasses and forbs as well as non-cultivated herbaceous upland vegetation dominated by native grasses and forbs.  Examples: golf courses, lawns, athletic fields, dry priaries and pastures.

4. Forest -

An upland area of land covered with woody perennial plants, the tree reaching a mature height of at least 6 feet tall with a definite crown.  To be considered a forested cover type the stand must have a combined species minimum of 3 cords/acre or 1,251 bdft/acre or 251 stems per acre depending on size class (MNCSA Standards) Note: all forest  training sites were obtained from the MNDNR Forest Inventory and Management (FIM) dataset and thus an effort was made to match the cover type descriptions between the two data sets within the limitations of remote sensing capabilities.  Examples: white pine, red pine, oak, mixed conifer and mixed deciduous.

5. Water -

An area of open water with none or very little above surface vegetaton.  Example:lakes, streams, rivers and open wetlands.

6. Wetland -

A lowland area with a cover of persistent and non-persistent herbaceous plants standing above the surface of wet soil or water.  Examples: cattails, march grass, sedges and peat.

7. Shrubland -

An upland or lowland area with vegetation that has a persistent woody stem, generally with several basal shoots, low growth of less than 20 feet in height. Area has less than 251 stems per acre of commercial tree species, the shrub species are fairly uniformly distributed throughout and the density of the coverage is moderate to high. (Examples: alder, willow, buckthorn, hazel, sumac, and scrub oak)  Note: all shrubland  training sites were obtained from the MNDNR Forest Inventory (CSA) and thus an effort was made to match the cover type descriptions between the two data sets within the limitations of remote sensing capabilities.

This data may be used for educational and non-commercial purposes, provided proper attribution is given. Secondary distribution of the data is permitted, but not supported by the University of Minnesota. By accepting the data, the user agrees not to transmit this data or provide access to it or any part of it to another party unless the user includes with the data a copy of this disclaimer.

see website or contact info