Carroll diagrams.. ?

[anteater]

dd1 has forgot her text book but remembered her homework.. Questions all about Carroll diagrams, anyone know what they are?

Someone must know, just soent 20 useless mins working thro the rubbish google answers...

They're rectangular grids that sort by yes/no answers - so if you were going to sort numbers by whether they were odd or even, you would have a grid of four rectangles, two underneath the other, with "odd" and "even" in the top two grids, then the numbers sorted in the rectangles underneath.

That sounds crap; let me see if I can find something on google that might explain it better!

Aren't they like VENN diagrams

Have a look at \link{http://io.uwinnipeg.ca/~jameis/Math/L.venn/LEY1.html\this} - part way down. Which strangely enough uses odd and even to demonstrate!

Thank you!

Carroll diagrams are rectangular tables that display data in a yes/no way. They are named in honour of Lewis Carroll, the pseudonym of the author of Alice in Wonderland. He was a mathematician who specialized in symbolic logic.

Suppose you have 1, 2, 3, 4, 5, 6, 7, and one attribute - evenness. The Carroll diagram for this is:

even not even

2 4 6 1 3 5 7

but do it in a table form ( can't draw boxes on here)