Notations
nVariables and individual scores
nCapital letters, (X, Y) indicate variables
nThe score for subject 4 would be written X4
nSums
nThe upper case Greek sigma to indicate "the sum
of"
nLower case n for the number of subjects in a sample
nUpper case N for the number of subjects in population
nRaw data X1 X2 X3 X4
3 5 1 2
Note: the sample size is n = 4