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The DISCRIM Procedure |
When the input data set is TYPE=CORR, TYPE=COV, or TYPE=CSSCP, PROC DISCRIM reads the number of observations for each class from the observations with _TYPE_='N' and reads the variable means in each class from the observations with _TYPE_='MEAN'. PROC DISCRIM then reads the within-class correlations from the observations with _TYPE_='CORR' and reads the standard deviations from the observations with _TYPE_='STD' (data set TYPE=CORR), the within-class covariances from the observations with _TYPE_='COV' (data set TYPE=COV), or the within-class corrected sums of squares and cross products from the observations with _TYPE_='CSSCP' (data set TYPE=CSSCP).
When you specify POOL=YES and the data set does not include any observations with _TYPE_='CSSCP' (data set TYPE=CSSCP), _TYPE_='COV' (data set TYPE=COV), or _TYPE_='CORR' (data set TYPE=CORR) for each class, PROC DISCRIM reads the pooled within-class information from the data set. In this case, PROC DISCRIM reads the pooled within-class covariances from the observations with _TYPE_='PCOV' (data set TYPE=COV) or reads the pooled within-class correlations from the observations with _TYPE_='PCORR' and the pooled within-class standard deviations from the observations with _TYPE_='PSTD' (data set TYPE=CORR) or the pooled within-class corrected SSCP matrix from the observations with _TYPE_='PSSCP' (data set TYPE=CSSCP).
When the input data set is TYPE=SSCP, the DISCRIM procedure reads the number of observations for each class from the observations with _TYPE_='N', the sum of weights of observations for each class from the variable INTERCEP in observations with _TYPE_='SSCP' and _NAME_='INTERCEPT', the variable sums from the variable=variablenames in observations with _TYPE_='SSCP' and _NAME_='INTERCEPT', and the uncorrected sums of squares and cross products from the variable=variablenames in observations with _TYPE_='SSCP' and _NAME_='variablenames'.
When the input data set is TYPE=LINEAR, TYPE=QUAD, or TYPE=MIXED, PROC DISCRIM reads the prior probabilities for each class from the observations with variable _TYPE_='PRIOR'.
When the input data set is TYPE=LINEAR, PROC DISCRIM reads the coefficients of the linear discriminant functions from the observations with variable _TYPE_='LINEAR'.
When the input data set is TYPE=QUAD, PROC DISCRIM reads the coefficients of the quadratic discriminant functions from the observations with variable _TYPE_='QUAD'.
When the input data set is TYPE=MIXED, PROC DISCRIM reads the coefficients of the linear discriminant functions from the observations with variable _TYPE_='LINEAR'. If there are no observations with _TYPE_='LINEAR', PROC DISCRIM then reads the coefficients of the quadratic discriminant functions from the observations with variable _TYPE_='QUAD'.
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