pFrd {NSM3}

Function to compute the P-value for the observed Friedman, Kendall-Babington Smith S statistic.

Description

The method used to compute the P-value is from the reference by Van de Wiel, Bucchianico, and Van der Laan.

Usage

pFrd(x,b=NA,trt=NA,method=NA, n.mc=10000)

Arguments

x

Either a matrix or a vector containing the data.

b

If x is a vector, b is a required vector of block labels. Otherwise, not used.

trt

If x is a vector, trt is a required vector of treatment labels. Otherwise, not used.

method

Either "Exact", "Monte Carlo" or "Asymptotic", indicating the desired distribution. When method=NA, "Exact" will be used if the number of permutations is 10,000 or less. Otherwise, "Monte Carlo" will be used.

n.mc

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

Details

The data entry is intended to be flexible, so that the data can be entered in either of two ways. The following are equivalent:

pFrd(x=matrix(c(1,2,3,4,5,6),ncol=2,byrow=T)) pFrd(x=c(1,2,3,4,5,6),b=c(1,1,2,2,3,3),trt=c(1,2,1,2,1,2))

Value

Returns a list with "NSM3Ch7p" class containing the following components:

k

number of treatments in the data

n

number of blocks in the data

obs.stat

the observed D statistic

p.val

upper tail P-value

Author(s)

Grant Schneider

References

Van de Wiel, M. A., A. Di Bucchianico, and P. Van der Laan. "Symbolic computation and exact distributions of nonparametric test statistics." Journal of the Royal Statistical Society: Series D (The Statistician) 48.4 (1999): 507-516.

See Also

Also see the coin package.

Examples

##Hollander-Wolfe-Chicken Example 7.1 Rounding First Base
rounding.times<-matrix(c(5.40, 5.50, 5.55,
                         5.85, 5.70, 5.75,
                         5.20, 5.60, 5.50,
                         5.55, 5.50, 5.40,
                         5.90, 5.85, 5.70,
                         5.45, 5.55, 5.60,
                         5.40, 5.40, 5.35,
                         5.45, 5.50, 5.35,
                         5.25, 5.15, 5.00,
                         5.85, 5.80, 5.70,
                         5.25, 5.20, 5.10,
                         5.65, 5.55, 5.45,
                         5.60, 5.35, 5.45,
                         5.05, 5.00, 4.95,
                         5.50, 5.50, 5.40,
                         5.45, 5.55, 5.50,
                         5.55, 5.55, 5.35,
                         5.45, 5.50, 5.55,
                         5.50, 5.45, 5.25,
                         5.65, 5.60, 5.40,
                         5.70, 5.65, 5.55,
                         6.30, 6.30, 6.25),ncol=3,byrow=TRUE)
#pFrd(rounding.times,n.mc=20000)
pFrd(rounding.times,n.mc=2000)