Analysis of variance LANGUAGE Fortran DESCRIPTION AND PURPOSE

Given a set of root mean squares obtained from the analysis of a factorial ex periment one method of testing the signicance andor examining for evidence of certain types of error is to draw a halfnormal plot of these values Daniel The subroutine takes such a set of root mean squares and plots them on a halfnormal probability scale via the line printer or other device For this sort of application the accuracy of the average line printer is more than adequate This routine is a Fortran version of that appearing in Griths and Hill originally Sparks It uses character variables rather than storing character information in integers which was the only way of implementing such an algorithm in standard Fortran Where possible data statements have been replaced by parameter statements The code has been tidied up considerably and all output conned to a single routine to facilitate user tailoring of the nal plot A number of minor errors in a declared array length and format statements have been removed The only minor change to the plotting algorithm is in the range of values assigned to each line of the plot Specically the ith line of the plot i IDEPTH contains values in the range y Y STEP y Y STEP where y i IDEPTH Y STEP obsmaxIDEPTH obsmax is the maxi mum value to be plotted and IDEPTH denes the number of lines to be used in the plot The original algorithm used the range y Y STEP y Y STEP which does not give such an even distribution of point