NSM3 (version 1.18)

pKolSmirn: Function to copute the P-value for the observed Kolmogorov-Smirnov J statistic.

Description

This function uses psmirnov2x from the base stats package to compute the J statistic and corresponding P-value. The program is reasonably quick for large data, well after the asymptotic approximation suffices, so Monte Carlo methods are not included. This function primarily serves as a wrapper to the ks.test function with the output standardized to the format of the other functions included in the NSM3 package.

Usage

pKolSmirn(x,y=NA,g=NA,method=NA,n.mc=10000)

Value

Returns a list with "NSM3Ch5p" class containing the following components:

m

number of observations in the first data group (X)

n

number of observations in the second data group (Y)

obs.stat

the observed C statistic

p.val

upper tail P-value

Arguments

x

Either a list or a vector containing either all or the first group of data.

y

If x contains the first group of data, y contains the second group of data. Otherwise, not used.

g

If x contains a vector of all of the data, g is a vector of 1's and 2's corresponding to group labels. Otherwise, not used.

method

Either "Exact" or "Asymptotic", indicating the desired distribution. When method=NA, "Exact" will be used.

n.mc

If method="Monte Carlo", the number of Monte Carlo samples used to estimate the distribution. Otherwise, not used.

Author

Grant Schneider

Details

The data entry is intended to be flexible, so that the two groups of data can be entered in any of three ways. For data a=1,2 and b=3,4 all of the following are equivalent:

pKolSmirn(x=c(1,2),y=c(3,4)) pKolSmirn(x=list(c(1,2),c(3,4))) pKolSmirn(x=c(1,2,3,4),g=c(1,1,2,2))

See Also

Also see ks.test().

Examples

##Hollander-Wolfe-Chicken Example 5.4 Effect of Feedback on Salivation Rate:
feedback<-c(-0.15, 8.6, 5, 3.71, 4.29, 7.74, 2.48, 3.25, -1.15, 8.38)
no.feedback<-c(2.55, 12.07, 0.46, 0.35, 2.69, -0.94, 1.73, 0.73, -0.35, -0.37)
pKolSmirn(x=feedback,y=no.feedback)