Table 1. Results of robust model for Hungary 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
1991 1992 1993 
OSD Rob. Diff. OSD Rob. Diff. OSD Rob Diff. 
Corn 67.1 64.8 -2.3 36.5 36.0 -0.5 35.0 33.7 -1.3 
Wheat 51.9 47.7 4.2 40.7 45.0 4.3 30.5 33.4 2.9 
Sunflower 20.7 20.3 -0.4 17.8 18.3 0.5 17.8 18.1 0.3 
Sugar Beet 37.2 37.7 0.5 27.2 26.0 -1.2 23.0 24.5 1.5 
Barley 43.6 39.0 -4.6 35.9 36.6 0.7 26.4 27.4 1.0 
Alfalfa 58.1 58.7 0.6 43.0 44.8 1.8 38.3 38.8 0.5 
OSD: Official Statistical Data 
Rob.: Yield data estimated by robust model 
Diff.: Difference between Rob. and OSD 
The values are in 100 kg/ha, except the sugar beet where t/ha. 
5. CONCLUSIONS 
By the results of the previous section it seems that the 
extension of the method for the entire country was 
successful. However the method needs more refinements, 
and at some points the setting of parameters requires 
further studies. To achieve this we need a lot more 
reliable satellite data than we had so far. By the way the 
method can be experimentally used operationally parallel 
to the traditional estimating methods. 
REFERENCES 
Ferencz Cs., Tarcsai Gy., Lichtenberger J., 1993. 
Correction of atmospheric effects of satellite remote 
sensing data (Landsat MSS-NOAA AVHRR) for surface 
canopy investigations. Int. J. Remote Sensing, 14(18), 
pp. 3417-3431. 
Hamar D., Ferencz Cs., Lichtenberger J., Tarcsai Gy., 
Ferencz-Árkos L, 1996. Yield estimation for corn and 
wheat in the Hungarian Great Plain using Landsat MSS 
data. Int. J. Remote Sensing, 17(9), pp. 1689-1699. 
Lichtenberger J., Ferencz Cs., Tarcsai Gy., Timár G., 
1995. New atmospheric correction method for Landsat 
TM data: The ACABA algorithm. Annales Univ. Sci. Bp. 
R. Eótvós, Sec. Geophys. Meteor., Tom. XI, pp. 137- 
164. 
  
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800 Intemational Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998