Table 1
Confusion matrices
USFS Old Growth versus Wilderness Society's Ancient Forest
Off-diagonal elements split into attribute and position error

(a) Olympic National Forest

		Ancient Forest		Not Ancient Forest
Old		102,999	16.4%
	Attribute			26,950	4.3%
Growth	Position			16,010	2.5%
Not	Attribute	77,706	12.4%
Old	Position	15,903	2.5%
Growth				389,000	61.9%

(b) Mt. Baker-Snoqualmie National Forest

		Ancient Forest		Not Ancient Forest
Old		404,191	23.2%
	Attribute			165,561	9.5%
Growth	Position			59,816	3.4%
Not	Attribute	121,441	7.0%
Old	Position	60,488	3.5%
Growth				932,000	53.5%

(c) Gifford Pinchot National Forest

		Ancient Forest		Not Ancient Forest
Old		222,589	19.1%
	Attribute			164,132	14.1%
Growth	Position			104,027	8.9%
Not	Attribute	48,978	4.2%
Old	Position	20,069	1.7%
Growth				606,000	52.0%

(d) Mt. Hood National Forest

		Ancient Forest		Not Ancient Forest
Old		157,533	22.2%
	Attribute			137,493	19.4%
Growth	Position			50,955	7.2%
Not	Attribute	51,762	7.3%
Old	Position	22,472	3.2%
Growth				289,000	40.7%

Table 2
Confusion matrices
USFS Old Growth versus Wilderness Society's Old Growth
Off-diagonal elements split into attribute and position error

(a) Olympic National Forest

		*Old Growth*		Not Old Growth
Old		63,358	11.0%
	Attribute			48,138	8.3%
Growth	Position			25,697	4.5%
Not	Attribute	23,679	4.1%
Old	Position	4,103	0.7%
Growth				411,713	71.4%

(b) Mt. Baker-Snoqualmie National Forest

		*Old Growth*		Not Old Growth
Old		286,766	28.1%
	Attribute			87,722	8.6%
Growth	Position			17,059	1.7%
Not	Attribute	103,686	10.1%
Old	Position	32,357	3.2%
Growth				494,725	48.4%

(c) Gifford Pinchot National Forest

		*Old Growth*		Not Old Growth
Old		88,006	9.7%
	Attribute			251,976	27.8%
Growth	Position			24,037	2.6%
Not	Attribute	19,190	2.1%
Old	Position	8,980	1.0%
Growth				514,958	56.8%

(d) Mt. Hood National Forest

		Old Growth		Not Old Growth
Old		71,788	11.1%
	Attribute			209,132	32.4%
Growth	Position			34,065	5.3%
Not	Attribute	19,309	3.0%
Old	Position	9,386	1.5%
Growth				301,965	46.8%

Colorful bar

Last updated: July 20, 1998

Copyright 1996-98 Robert A. Norheim and IGU GISc Study Group