Saturday, April 5, 2014

Error detection, backtracking, and expert problem solving.




As I discussed in an earlier posting about a computer model of Sudoku, computers can solve puzzles very differently than humans do.  Because computers can be very fast and do a good job of systematically exploring a problem, you can give let them churn on a problem and exhaustively figure out the answer.  For something like Sudoku, it is easy to figure out if the answer is correct (it is just simple math, or really, it is just pattern sorting). Problems like Sudoku are sometimes called 'well-structured', meaning that you can tell if you are right or wrong.  Other puzzles, problems, and tasks are ill-structured; anything that is not well-structured.

Wednesday, April 2, 2014

Human and Machine Problem Solving in Sudoku (and crosswords)






A new preprint in Arxiv by Radek Pel├ínek takes a look at human problem solving of Sudoku, and has been picked up by various media sources (see The medium,  and slashdot)
Above is a picture of how well their new method predicts solution times across several hundred puzzles.