Here is a list of top 10 Data Science writers on Quora and their selected answers. Next, play around some more and check out the tutorials for Titanic: Machine Learning from Disaster with a slightly more complicated binary classification task (with categorical variables, missing values, etc.), Software Engineer at Arista Networks, Foundation Member and Game Dev at GNOME. You may be wrong but consider it to be a healthy discussion, the interviewer will help you along the way. Its almost never necessary to get the correct answer, most interviewers care about your basics and how you think. There is a lot of value in getting really deep technical expertise.