— to initiate a programme for the collection and statistical processing of data 
required for the establishment of actual cost models. 
The subsequent paragraphs of this paper will present a first analysis of 
the problem as a basis for further discussion and elaboration. 
2 Cost Models 
In the first instance cost models, as desired for the purposes mentioned 
above, can generally be defined as the functional relationships between the cost 
per production unit of any of the different sub-processes of a total production 
process (e.g. cost per line km of aerial photography, cost of aerial triangulation 
per model, cost of stereoplotting per km? etc) and the large number of factors 
which influence the production. 
These cost models are, on the one hand, a function of what will be called 
Basic Cost Standards being personnel - costs/time unit, equipment/costs/time - 
unit, and material costs/unit; and on the other hand a function of what will be 
called Production Standards, these being the statistically derived data concern- 
ing personnel and equipment-time required to realise a certain production unit, 
including the materials thereby required (see figure 1). 
  
basic cost standards 
  
  
personnel costs/time unit 
  
equipment costs/time unit 
material costs/unit 
  
  
  
cost models 
  
  
cost/prod unit 
  
  
  
production standards 
  
  
  
required personnel times/prod unit 
required equipment times/prod unit 
required materials/prod unit 
  
  
  
figure 1 relation between cost models, basic cost standards and production standards