extensions [ stats ]

to setup
  clear-all
  crt 5 [ fd 10 ]
end

to go
  ; Create some data as nested list (two variables for each turtle):
  let data [(list xcor ycor)] of turtles

  ; Create a stats table:
  let tbl stats:newtable-from-row-list data

  ; Calculate a correlation matrix with `stats:correlation`:
  let cor-list stats:correlation tbl

  ; In 2x2 case you can use the second element from the first row to get the coefficient:

  print item 0 item 1 cor-list
end