I was perusing my copy of Penguin's Dictionary of Mathematics (David Nelson, editor) -- a wonderful book, btw -- in the bathroom [yes:)] and having randomly ope

I was perusing my copy of Penguin's Dictionary of Mathematics (David Nelson, editor) -- a wonderful book, btw -- in the bathroom [yes:)] and having randomly opened the book to Youden Square decided to take a closer look on the web. Wikipedia search for the term brings up the page on Combinatorial design. This is an interesting case of a general terminology having a very narrow technical meaning. The "design" here means design of experiments. And apparently constructs like the Youden Square are used to design experiment that are conducted to determine causation. The following link provides a relatively accessible introduction: Basic Experiment Design http://www.math.unm.edu/~fletcher/SUPER/chap17.pdf http://www.math.unm.edu/~fletcher/SUPER/chap17.pdf -- https://www.goodreads.com/book/show/6362666-the-penguin-dictionary-of-mathematics https://www.goodreads.com/book/show/6362666-the-penguin-dict...