That said, if it's possible to do better than random guessing, then does this reflect the fact that the five charts are presumably hand-selected to be "interesting"?
My naive guess, and I'd be very curious to learn if this were wrong, is that something very close to the efficient market hypothesis is true; that, if it were possible to beat the monkeys on randomly chosen stocks on random dates, then someone would have figured this out already and deployed bots to capture whatever profits are available.
Your description here and on the website is not clear to me about what I am predicting. Am I predicting whether the stock is going to continue to go up the same day? Is the chart of one day and I am predicting whether it will go up or down the next day? In my opinion, you need to get the explanation of what I'm looking at and the directions of what I am predicting down to one clear sentence.
“They have different goals”, I hear. Literally nobody’s investment strategy involves passing up above-average returns for low risk.
Maybe Volume would be useful though.