experiments | to 5 e i = 0 
10 uw. vo 
H Xy 
y 
53 g 
experiment 6 g o 
P x ry xy 
An artificial v.c. matrix is used as the a priori v.c. matrix for the 
ground control points. : 
This so-called substitute matrix was generated via a linear choice 
function formula 3.1 introduced by Baarda in [2] and for example 
used by Molenaar et al. in [6]. 
42; m'adfrace ile 3.3 
ij 17ij 
In 3.1 the following quantities occur 
2 . . 
d..: choice function 
1] 
1,3} expresses the distance between two points 
Cj; 28 constant which for all experiments is fixed on c.=2. 
This value is commonly used in The Netherlands when dealing 
with cirquit networks 
2 : ; i : nass 
Ad : with this parameter the uncertainty of the point definition 
is expressed for this purpose. Ad2 is fixed on Ad? = 0, 
The S-bases of the blocks are chosen in such a way that the two base 
points are lying diagonally opposite each other, each in a corner of the 
block. 
4. SOME FURTHER REMARKS ON THE EXPERIMENTS 
For each block adjustment the following steps can be distinguished. 
l. The generation of the block. 
2. The free independent modelblock adjustment, that is only the tie- 
points are taken into consideration. 
3. The connection of the adjusted free block to the ground control. 
This is done by a pseudo least squares adjustment, which means that 
the ground control points are not corrected after adjustment. 
However, by applying a special case of the law of propagation their 
V.c. matrix is taken into account when evaluating the precision 
of the adjustment results (see also [3] and [5] ). The in chapter 3 
introduced substitute matrix is used as v.c. matrix for the ground 
control points. 
4. In the fourth step the evaluation of the precision of the adjustment 
results (both the free block adjustment and the pseudo least 
squares adjustment) is carried out. 
This is done with aid of the general eigen value problem 
|G- \H| = 0 4.1 
In 4.1 the G-matrix is the v.c. matrix that has to be evaluated; 
whereas the H-matrix is a criterion matrix which is calculated in the 
same way as the before-mentioned substitute matrix (in this case c,=1) 
and has the same S-base as the G-matrix. 
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