Brainerd-Robinson Coefficient of Similarity in R

br.r

# function to load the observations
load = function() {
  p <- read.csv("observations.csv")  
  rownames(p) <- p[,1]
  p <- p[,c(2:6)]
  return(p)
}

# function to compute the normalized Brainerd-Robinson similarity for observations x
BR <- function(x) 
{
  rd <- dim(x)[1]
  results <- matrix(0,rd,rd)
  for (s1 in 1:rd) {
    for (s2 in 1:rd) {
      results[s1,s2] <- 1 - (sum(abs(x[s1, ] / sum(x[s1,]) - x[s2, ] / sum(x[s2,]))))/2
    }
  }
  rownames(results) <- rownames(x)
  colnames(results) <- rownames(x)
  return(results)
}

# load observations, compute Brainerd-Robinson similarity and write results to file
write.csv(BR(load()), "br.csv")

observations.csv

references.bib

@article{robinson1951method,
  title={A method for chronologically ordering archaeological deposits},
  author={Robinson, William S},
  journal={American antiquity},
  volume={16},
  number={4},
  pages={293--301},
  year={1951},
  publisher={JSTOR}
}

@article{brainerd1951place,
  title={The place of chronological ordering in archaeological analysis},
  author={Brainerd, George W},
  journal={American antiquity},
  volume={16},
  number={4},
  pages={301--313},
  year={1951},
  publisher={JSTOR}
}

@misc{weidele2015brsim,
    author={Daniel Weidele},
    title={{Normalized Brainerd-Robinson Similarity in R}},
    year={2015},
    howpublished={\url{https://gist.github.com/dweidele/10561e02e5b189161a5c}},
    note={[{Online at GitHub Gist}; accessed dd.MM.yyyy]}
}