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- C
- C ..................................................................
- C
- C SUBROUTINE SMIRN
- C
- C PURPOSE
- C COMPUTES VALUES OF THE LIMITING DISTRIBUTION FUNCTION FOR
- C THE KOLMOGOROV-SMIRNOV STATISTIC.
- C
- C USAGE
- C CALL SMIRN(X,Y)
- C
- C DESCRIPTION OF PARAMETERS
- C X - THE ARGUMENT OF THE SMIRN FUNCTION
- C Y - THE RESULTANT SMIRN FUNCTION VALUE
- C
- C REMARKS
- C Y IS SET TO ZERO IF X IS NOT GREATER THAN 0.27, AND IS SET
- C TO ONE IF X IS NOT LESS THAN 3.1. ACCURACY TESTS WERE MADE
- C REFERRING TO THE TABLE GIVEN IN THE REFERENCE BELOW.
- C TWO ARGUMENTS, X= 0.62, AND X = 1.87 GAVE RESULTS WHICH
- C DIFFER FROM THE SMIRNOV TABLES BY 2.9 AND 1.9 IN THE 5TH
- C DECIMAL PLACE. ALL OTHER RESULTS SHOWED SMALLER ERRORS,
- C AND ERROR SPECIFICATIONS ARE GIVEN IN THE ACCURACY TABLES
- C IN THIS MANUAL. IN DOUBLE PRECISION MODE, THESE SAME
- C ARGUMENTS RESULTED IN DIFFERENCES FROM TABLED VALUES BY 3
- C AND 2 IN THE 5TH DECIMAL PLACE. IT IS NOTED IN
- C LINDGREN (REFERENCE BELOW) THAT FOR HIGH SIGNIFICANCE LEVELS
- C (SAY, .01 AND .05) ASYMPTOTIC FORMULAS GIVE VALUES WHICH ARE
- C TOO HIGH ( BY 1.5 PER CENT WHEN N = 80). THAT IS, AT HIGH
- C SIGNIFICANCE LEVELS, THE HYPOTHESIS OF NO DIFFERENCE WILL BE
- C REJECTED TOO SELDOM USING ASYMPTOTIC FORMULAS.
- C
- C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
- C NONE
- C
- C METHOD
- C THE METHOD IS DESCRIBED BY W. FELLER-ON THE KOLMOGOROV-
- C SMIRNOV LIMIT THEOREMS FOR EMPIRICAL DISTRIBUTIONS- ANNALS
- C OF MATH. STAT., 19, 1948, 177-189, BY N. SMIRNOV--TABLE
- C FOR ESTIMATING THE GOODNESS OF FIT OF EMPIRICAL
- C DISTRIBUTIONS- ANNALS OF MATH. STAT., 19, 1948, 279-281,
- C AND GIVEN IN LINDGREN, STATISTICAL THEORY, THE MACMILLAN
- C COMPANY, N. Y., 1962.
- C
- C ..................................................................
- C
- SUBROUTINE SMIRN(X,Y)
- C DOUBLE PRECISION X,Q1,Q2,Q4,Q8,Y
- C
- C IF A DOUBLE PRECISION VERSION OF THIS ROUTINE IS DESIRED, THE C
- C IN COLUMN ONE OF THE DOUBLE PRECISION CARD ABOVE SHOULD BE
- C REMOVED, AND THE C IN COLUMN ONE OF THE STATEMENTS NUMBERED
- C C 3, C 5, AND C 8 SHOULD BE REMOVED, AND THESE CARDS
- C SHOULD REPLACE THE STATEMENTS NUMBERED 3, 5, AND 8,
- C RESPECTIVELY. ALL ROUTINES CALLING THIS ROUTINE MUST ALSO
- C PROVIDE DOUBLE PRECISION ARGUMENTS TO THIS ROUTINE.
- C
- C ..................................................................
- C
- IF(X-.27)1,1,2
- 1 Y=0.0
- GO TO 9
- 2 IF(X-1.0)3,6,6
- 3 Q1=EXP(-1.233701/X**2)
- C 3 Q1=DEXP(-1.233700550136170/X**2)
- Q2=Q1*Q1
- Q4=Q2*Q2
- Q8=Q4*Q4
- IF(Q8-1.0E-25)4,5,5
- 4 Q8=0.0
- 5 Y=(2.506628/X)*Q1*(1.0+Q8*(1.0+Q8*Q8))
- C 5 Y=(2.506628274631001/X)*Q1*(1.0D0+Q8*(1.0D0+Q8*Q8))
- GO TO 9
- 6 IF(X-3.1)8,7,7
- 7 Y=1.0
- GO TO 9
- 8 Q1=EXP(-2.0*X*X)
- C 8 Q1=DEXP(-2.0D0*X*X)
- Q2=Q1*Q1
- Q4=Q2*Q2
- Q8=Q4*Q4
- Y=1.0-2.0*(Q1-Q4+Q8*(Q1-Q8))
- 9 RETURN
- END