Determination of scales
What information do we have?
Scales are determined by comparison of symmetry-related reflections, ie by adjusting scale factors to get the best internal consistency of intensities. Note that we do not know the true intensities and an internally-consistent dataset is not necessarily correct. Systematic errors will remain
Minimize F = Shl whl (Ihl - 1/khl<Ih>)2
Ihl l’th intensity observation of reflection h
khl scale factor for Ihl <Ih> current estimate of Ih
khl is a function of the parameters of the scaling model