What does this statement mean - "Measurements are nearly always of individual differences"
And WHAT tools do we have that will allow us to interpret individual measures?
My thinking for the first part of the question is something like, the reporting of a score can seldom be understood out of context, it can be understood only in relation to other scores.
The second part regarding the tools is: standard score, percentile, age or grade level. The essence of each of those are comparision of an individual to a defined group. All these measurements are different, but each can be used to compare a new subject with many others in the group that have preceded it.
Is my thinking logical and or correct?