In I.4: "The brightest spot is near the center, where most of the values cluster, but every so often circles are drawn farther to the right or left of the center." should read "The darkest spot is near the center, where most of the values cluster, but every so often circles are drawn farther to the right or left of the center."
In I.4: "The brightest spot is near the center, where most of the values cluster, but every so often circles are drawn farther to the right or left of the center." should read "The darkest spot is near the center, where most of the values cluster, but every so often circles are drawn farther to the right or left of the center."
This is in the very end of section I.4