P
terms of the weight coefficients of the coordinates XjYj, XuYu and
the same result would be obtained as if the formula 2 is
used and expanded in terms of X\ and Y[ only, the stations i
being indicated by fictitious coordinates X{Yi. This would facilitate
the calculation considerably.
In the subsequent reasoning the plausible assumption is made
that there is no correlation between any observation ai and another
observation ay, or between observations ai and any given coor
dinates, so that the corresponding weight coefficients are zero.
It is then derived that formula 12 will not contain the third term
at the right hand side and becomes:
244
700-
600-
500-
400-
300-
200-
100-
T
9
~l
10
T
8
T
2
T
3
T
4
T
5
T
6
1
7
Figuur 5
