3/1才交申请，3/9推荐人才把推荐信交了，3/12收到面试邀请。（感觉学校效率好高啊） 3/22早上10am面试David Uminsky。

工作了几年(非tech），学校的东西早就忘了。虽然复习了两天还有大神带着过，但是对统计、线代、python的理解只停留表面以至于追问都答不上来。

还是很感谢cd上的童鞋们分享的面经，面试的问题基本都中。回馈大家分享一下面试题：

Stats:

• A, B independent events, what's the prob (A|B)
• box and whisker plot
• 95% interval
• A study shows that tutoring hours and grade are negatively correlated, can we say that tutoring harms students’ academic performance?

Linear Algebra:

• Given 5 3-dimensional vectors, can you explain what does linear dependent mean?
• Intuitively what can you tell by looking at the 5 vectors? (David: they are dependent because 3 dimension vectors have only 3 directions, 5 vectors must mean there are two redundant)
• Given a matrix A, explain what is Eigenvector and Eigenvalue?
• If A is invertible, what can we tell about eigenvalue? (David: eigenvalue is not zero)

Python: （share screen, read code what does the code return）

• return average
• return index of the maximum