8999 REM ******* REVISED APRIL, 1972  BY ED BAKER *******
9000 REM ***** CHISQ ***** STATISTICS PROGRAM *****
9001 REM ***** VERSION1 ***** 7/31/69/ *****
9002 REM CHI-SQUARE PROBABILITY
9003 PRINT "ENTER THE CHI-SQUARE VALUE AND THE DEGREES OF FREEDOM."
9004 INPUT G1,M
9005 LET N=1000
9006 LET G=G1/M
9007 LET P=1
9008 IF G*M*N=0 THEN 9031
9009 IF G<1 THEN 9014
9010 LET A=M
9011 LET B=N
9012 LET F=G
9013 GOTO 9017
9014 LET A=N
9015 LET B=M
9016 LET F=1/G
9017 LET A1=2/(9*A)
9018 LET B1=2/(9*B)
9019 LET Z=ABS((1-B1)*F^(.333333)-1+A1)
9020 LET Z=Z/SQR(B1*F^(.666667)+A1)
9021 IF B<4 THEN 9025
9022 LET P=(1+Z*(.196854+Z*(.115194+Z*(.000344+Z*.019527))))^4
9023 LET P=.5/P
9024 GOTO 9027
9025 LET Z=Z*(1+.08*Z^4/B^3)
9026 GOTO 9022
9027 IF G<1 THEN 9029
9028 GOTO 9033
9029 LET P=1-P
9030 GOTO 9033
9031 PRINT "YOU HAVE ERRED - INPUT THE TWO VALUES AGAIN"
9032 GOTO 9004
9033 PRINT
9034 PRINT
9035 PRINT 'EXACT PROBABILITY OF CHI-SQUARE='G1;'WITH 'M;'D.F.';
	'IS 'INT(100000*P)/100000
9999 END