9000  REM  CORREL--COMPUTES A CORRELATION COEFFICIENT
9002  READ N
9004  LET S1=0
9006  LET S2=0
9008  LET S3=0
9010  LET S4=0
9012  LET S5=0
9014  FOR I=1 TO N
9016  READ X,Y
9018  LET S1=S1+X
9020  LET S2=S2+Y
9022  LET S3=S3+X*Y
9024  LET S4=S4+X*X
9026  LET S5=S5+Y*Y
9028  NEXT I
9030  PRINT "THE CORRELATION COEFFICIENT = ";
9032  LET A=N*S3-S1*S2
9034  LET B=SQR((N*S4-S1^2)*(N*S5-S2^2))
9036  LET A=INT(A/B*1000+.5)/1000
9038  PRINT A
9900  DATA 5
9901  DATA 1,5,2,3,3,0,4,-5,5,-
9999  END