The section labeled Confusion Matrix is similar to those used before. Here, we can see where our rules went wrong. The key is displayed on the right, with a = edible and b = poisonous. Table columns indicate the predicted class of the mushroom while the table rows separate the 4,208 edible mushrooms from the 3,916 poisonous mushrooms. Examining the table, we can see that although the 1R classifier did not classify any edible mushrooms as poisonous, it did classify 120 poisonous mushrooms as edible—which makes for an incredibly dangerous mistake!