Geoscience Reference
In-Depth Information
Table 17.4 Confusion Matrix for COM2 vs. REF by Strata and Substrata; F Denotes Forest Cells and N
Denotes Nonforest Cells
REF
Substratum
NW
NE
SW
SE
Total
F
NF
NF
NF
N
12
7
19
35
4
2
6
12
4
16
15
7
2
9
6
0
6
10
0
19
19
4
0
4
40
0
21
21
16
9
19
6
6
19
4
21
100
35
15
10
40
F
N
F
N
North
South
Stratum
REF for the south stratum. This disagreement at the stratum level is reflected in the component of
disagreement at the stratum level in Figure 17.7. In contrast, Table 17.4 shows perfect agreement
at the stratum level; hence, Figure 17.8 shows no component of disagreement between COM2 and
REF at the stratum level.
17.4 DISCUSSION
17.4.1
Common Applications
The three maps in Figure 17.2 represent a common situation in map comparison analysis. There
are many applications where a scientist wants to know which of two maps is more similar to a
reference map. Three likely applications are in remote sensing, simulation modeling, and land-
change analysis.
In remote sensing, when a scientist develops a new classification rule, the scientist needs to
compare the map generated by the new rule to the map generated by a standard rule. Two
fundamental questions are (1) Did the new method perform better than the standard method
concerning its estimate of the quantity of each category? and (2) Did the new method perform
better than the standard method concerning its specification of the location of each category? The
format of Figure 17.9 is an effective way to display the results, because it conveys the answer to
both of these questions quickly. Specifically, COM1 makes some error of quantity while COM2
