You are looking for what is known as the "Cayley distance" between vectors - an edit distance that allows only transpositions. RSeek mentions PerMallows (https://cran.r-project.org/web/packages/PerMallows/PerMallows.pdf) and Rankluster (https://cran.r-project.org/web/packages/Rankcluster/Rankcluster.pdf) as packages that support work with Cayley distances. It seems to me that distCayley() in Rankcluster does what you want. From the examples:
x=1:5 y=c(2,3,1,4,5) distCayley(x,y) 8 Cheers, Boris On Aug 6, 2015, at 9:51 AM, Federico Calboli <federico.calb...@helsinki.fi> wrote: >> >> On 6 Aug 2015, at 15:40, Bert Gunter <bgunter.4...@gmail.com> wrote: >> >> Define "goodness of match" . For exact matches, see ?"==" , all.equal, etc. > > Fair point. I would define it as a number that tells me how likely it is > that the same (noisy) process produced both lists. > > BW > > F > > > > >> >> Bert >> >> On Thursday, August 6, 2015, Federico Calboli <federico.calb...@helsinki.fi> >> wrote: >> Hi All, >> >> let’s assume I have a vector of letters drawn only once from the alphabet: >> >> x = sample(letters, 15, replace = F) >> x >> [1] "z" "t" "g" "l" "u" "d" "w" "x" "a" "q" "k" "j" "f" "n" “v" >> >> y = x[c(1:7,9:8, 10:12, 14, 15, 13)] >> >> I would now like to test how good a match y is for x. Obviously I can >> transform the letters in numbers and use a rank test, but I was left >> wondering whether this is the only solution and whether there are more >> appropriate solutions that are already implemented in R (I am not going to >> reinvent the wheel if I can avoid it). >> >> BW >> >> F >> >> >> -- >> Federico Calboli >> Ecological Genetics Research Unit >> Department of Biosciences >> PO Box 65 (Biocenter 3, Viikinkaari 1) >> FIN-00014 University of Helsinki >> Finland >> >> federico.calb...@helsinki.fi >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. >> >> >> -- >> Bert Gunter >> >> "Data is not information. Information is not knowledge. And knowledge is >> certainly not wisdom." >> -- Clifford Stoll >> > > > -- > Federico Calboli > Ecological Genetics Research Unit > Department of Biosciences > PO Box 65 (Biocenter 3, Viikinkaari 1) > FIN-00014 University of Helsinki > Finland > > federico.calb...@helsinki.fi > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.