What is a Estimable Quantity?

[Grazerr]

I am struggling to find a simple definition of an 'estimable quantity'.

I am interested in estimable quantities in relation to network adjustments using least squares. My current understanding is that an estimable quantity is a quantity that varies according to the constraints used in the least squares adjustment (i.e depends on the stations which are held fixed).

However I am confused and cannot find any simply definitions online. Is an estimable quantity the same as an variant quantity, which in terms of least squares network adjustments is

1. Adjusted observations, La
   
2. Variance covariance of matrix of the adjusted observations, ∑La
   
3. Estimated distances and angles and their variances - covariance’s (computed from the adjusted coordinates).
   
4. V, V^TPV, and σ_o

<sub>Thanks for helping me out

Grazerr</sub>

 

[kevin786]

It refers to simplifying equations using estimated values of its dependent variables. For example, you could use orders of 10 by shifting decimal places. In that case you would use .1, 1.0, 10.0 and so on.


regards,