DataScience

Hey everyone. I posted a thread a few days ago about being nervous about my first DS interview. The thread was taken down by mods due to it being more appropriate for the stickied thread. So I want to make this thread less about questions, but more of an informative post to show you some of the questions I was asked. Hopefully it’s helpful for newbies and veterans alike!

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SQL:

•	What is a view?
•	Is a table dynamic or static?
•	Difference between a primary key and foreign key
•	Inner Join vs. Left Join scenario (pretty sure it was from w3schools. ez pz)
•	WHERE vs. HAVING
•	When would you use a subquery? Provide an example
•	How would you improve the performance of a slow query?
•	EDIT: Some aggregation and GROUP by questions (MAX, AVG, COUNT, etc.) that I just remembered.

Python

•	Explanation of libraries I use (Pandas mainly)
•	How would you get the maximum result from a list?
•	Can you explain the concept of functions
•	Difference between FOR and WHILE loops?
•	Give some examples of how you would clean dirty data.

Tableau:

•	What is a calculated field? Provide some examples in your work
•	What is the difference between a live view and extract? When would you use each?
•	More information given on the data I work with

Statistics:

•	Explain what a p-value is to someone who has no idea what that is.
•	Explanation on linear/logistic regression modeling.
•	What is standard deviation? Examples?
•	Difference between STDEV and Variance?
•	What statistics do you currently work with? (Descriptive mainly… mean, median, mode, stdev, confidence intervals)

I advanced to round 3 immediately, which is pretty much a shoe-in according to the hiring manager. I am very excited because it seems like a great opportunity. Even if I don’t get it, I still felt like I interviewed very well and did my best. I am very proud of myself.

120k a year w/ benefits, bonuses, and training courses a week to help me learn more advanced DS concepts, Python, or whatever I want. I am so excited.