151 
transition probability 
land usage 
previous year 
exposition 
> 
Rule 
northern slope 
=> no wine 
cf = 90% 
wine 
sensor 
channels 
> 
> 
> 
> 
> 
> 
> 
land usage in 
training areas 
A 
water 
forest 
wine 
fruit 
Figure 4: Combination of evidence from multiple processsing models 
4. CONCLUSIONS AND FUTURE WORK 
Human image interpreters apply rules that derive addi 
tional evidence from ancillary data for identifying parti 
cular classes in a spectral classification. An example of 
such a rule is the following: 
Wine often grows on southern slopes between 50 and 
300 meters elevation. 
A MYCIN-like approach combining this type of rule 
with probabilities derived by statistical classification is 
described in (Desachy, 1989). Rather than interprete 
these rules on a pixel-by-pixel basis, we intend to trans 
late such a rule to an algorithm that computes additional 
evidence for land-use classes from the available geogra 
phic data. That is, the rule will be compiled into a 
dedicated processing model. Other sources of evidence 
in land-use classification lead to new types of processing 
models such as the transition probabilities between land- 
use classes, as handled in the work of H. Middelkoop at 
ITC Enschede (Janssen, 1990). 
Future work will concern the combination of evidence 
computed by multiple processing models including su 
pervised spectral classification, rules on ancillary data, 
and transition probabilités in parallel (figure 4). There 
are a number of alternate methods of combining eviden 
ce, such as MYCIN-type certainty factors (Buchanan, 
1984), the Bayesian method (as used in Middelkoop, 
1989), and the Dempster-Shafer approach (Gordon, 1985). 
At present and in future stages of the RESEDA research, 
we will be working on three levels in parallel, thus 
conforming to the following general guideline of the 
RESEDA project: 
- On the application level, we are becoming familiar 
with the user’s requirements, and we are trying to 
verify our methodology by cooperating with an 
environmental project. Currently, RESEDA is in 
volved in the Integrated Rhine Project (IRP), which 
is directed by the Environmental Ministery of the 
Federal State of Baden-Württemberg. One scientist 
from our team (a biologist) is permanently engaged 
in this part of the project.