A TYPE=SSCP data set contains an uncorrected sum of squares and crossproducts (SSCP) matrix. TYPE=SSCP data sets are produced by PROC REG when the OUTSSCP= option is specified in the PROC REG statement. You can also create a TYPE=SSCP data set by using PROC CORR with the SSCP option and specifying the data set option TYPE=SSCP in parentheses following the name of the OUTP= or OUT= data set. You can also create TYPE=SSCP data sets in a DATA step; in this case, TYPE=SSCP must be specified as a data set option.

The variables in a TYPE=SSCP data set include those found in a TYPE=CORR data set. In addition, there is a variable called
`Intercept`

that contains crossproducts for the intercept (sums of the variables). The SSCP matrix is stored in observations with `_TYPE_`

=’SSCP’, including a row with `_NAME_`

=’Intercept’. PROC REG also outputs an observation with `_TYPE_`

=’N’. PROC CORR includes observations with `_TYPE_`

=’MEAN’ and `_TYPE_`

=’STD’ as well. TYPE=SSCP data sets are used by the same procedures that use TYPE=CORR data sets.

The following statements create a TYPE=SSCP data set from the `SocEcon`

input data set created in Example A.1: A TYPE=CORR Data Set Produced by PROC CORR:

proc reg data=SocEcon outsscp=regsscp; model house=pop school employ services / noprint; run; quit;

proc print data=regsscp; run;

The data set is created by PROC REG and is displayed in Figure A.5.

Figure A.5: A TYPE=SSCP Data Set Produced by PROC REG

Five Socioeconomic Variables |

OBS | _TYPE_ | _NAME_ | Intercept | Pop | School | Employ | Services | House |
---|---|---|---|---|---|---|---|---|

1 | SSCP | Intercept | 12.0 | 74900 | 137.30 | 28000 | 1450 | 204000 |

2 | SSCP | Pop | 74900.0 | 597670000 | 857640.00 | 220440000 | 10959000 | 1278700000 |

3 | SSCP | School | 137.3 | 857640 | 1606.05 | 324130 | 18152 | 2442100 |

4 | SSCP | Employ | 28000.0 | 220440000 | 324130.00 | 82280000 | 4191000 | 486600000 |

5 | SSCP | Services | 1450.0 | 10959000 | 18152.00 | 4191000 | 320500 | 30910000 |

6 | SSCP | House | 204000.0 | 1278700000 | 2442100.00 | 486600000 | 30910000 | 3914000000 |

7 | N | 12.0 | 12 | 12.00 | 12 | 12 | 12 |