page.trend.test {crank} | R Documentation |
calculates the Page test for ordered alternatives.
page.trend.test(x,ranks=TRUE)
x |
a 2D matrix of ranks or observations. |
ranks |
Whether the values in x are ranks or observations. |
page.trend.test will accept a matrix of ranks where the rows represent methods (usually raters) and the columns represent related data objects. It apparently handles ties, but not missing values. For small values of k (methods) or N (data objects), page.trend.test will try to look up the tabled values (as in Siegel & Castellan (1988) for significance. For k,N > 3,20 or k,N > 4-10,12, a normal approximation is returned. Only one of these values will be returned.
If ranks is FALSE, the function ranks the values in x and then calculates the test. If the values are already ranks, it usually makes no difference.
ranks |
matrix of ranks |
mean.ranks |
mean ranks of data objects |
L |
value of the L statistic |
p.table |
whether the obtained L exceeded the table value for small k,N |
Z |
The normal approximation for larger k,N |
pZ |
the probability of the obtained normal value for larger k,N |
The Page test for ordered alternatives is slightly more powerful than the Friedman analysis of variance by ranks.
Jim Lemon - thanks to Mikhail Trofimov and Michael Kirchhof for discovering major errors in the function and supplying the corrections
Siegel, S. & Castellan, N.J.Jr. (1988) Nonparametric statistics for the behavioral sciences. Boston, MA: McGraw-Hill.
# Craig's data from Siegel & Castellan, p 186 soa.mat<-matrix(c(.797,.873,.888,.923,.942,.956, .794,.772,.908,.982,.946,.913, .838,.801,.853,.951,.883,.837, .815,.801,.747,.859,.887,.902),nrow=4,byrow=TRUE) page.trend.test(soa.mat)