There is a small error on page 318 of Python for Data Science for Dummies. You can find it near the middle of the page in the Tip text. The current text on the second line of that paragraph says, “k as a number near the squared number of available observations.” However, the text should really read, “k as a number near the squared root number of available observations.” The word root is missing, which obviously changes the mathematical meaning of the text. Please accept our apologies for the typo. Let me know if you find any other errors of a technical nature in the book at [email protected] and I’ll be sure to provide a blog post about it here. Thank you for your support!