# 2021 Data Science Interview Preparation Guide

## What you'll learn

- How to master a data science interview in 2021 with 150+ data science interview questions and answers
- The most common interview questions and answers on Machine Learning
- The most common interview questions and answers on Deep Learning
- The most common interview questions and answers on Statistics
- The most common interview questions on Culture Fit and how to answer using the STAR interview technique
- The most common interview questions and answers on Computer Science for Data Scientist interviews
- The best questions to ask your interviewer and the reason why these questions are so effective

## Course content

- 00:33List of questions
- Preview01:49

## Requirements

- Knowledge of basic data science and statistics terms
- Willingness to spend time practicing the interview questions

## Description

Being a data scientist is one of the most lucrative and future proof careers with Glassdoor naming it the best job in America for the third consecutive year in a row with great future growth prospects and a median base salary of $110,000. I have recently made the transition from being a PhD student in Computer Science to a Senior Data Scientist at a large tech company. In this course I give you all the questions and answers that I used to prepare for my data science interviews as well as the questions and answers that I now expect when I am giving interviews to potential data science candidates. The course provides a complete list of 150+ questions and answers that you can expects in a typical data science interview including questions on machine learning, neural networks and deep learning, statistics, practical experience, big data technologies, SQL, computer science, culture fit, questions for the interviewer and brainteasers.

**What questions will you learn the answer to? **

What is the bias-variance tradeoff?

How would you evaluate an algorithm on unbalanced data?

When would you use gradient descent (GD) over stochastic gradient descent (SDG), and vice-versa?

Why do segmentation CNNs typically have an encoder-decoder style / structure?

Why we generally use Softmax non-linearity function as last operation in-network?

You randomly draw a coin from 100 coins — 1 unfair coin (head-head), 99 fair coins (head-tail) and roll it 10 times. If the result is 10 heads, what is the probability that the coin is unfair?

Given the following statistic, what is the probability that a woman has cancer if she has a positive mammogram result? 1% of women have breast cancer, 90% of women who have breast cancer test positive on mammograms and 8% of women will have false positives.

Write a SQL query to get the second highest salary from the Employee table. If there is no second highest salary the query should return null.

What is the average time complexity to search an unsorted array?

Why do you want to work here?

How can you generate a random number between 1 – 7 with only a die?

**About the instructor:**

Senior Data Scientist at a large tech company

Recently finished PhD in Computer Science and moved to industry

5+ years teaching experience at university level

## Who this course is for:

- Academic wanting to transition from academic to an industry data scientist position
- Data analysts who want to move to a more senior data scientist position
- Students looking to become data analyst or data scientist

## Instructor

Hello, I am a senior data scientist from Ireland. I recently finished my PhD in Computer Science and I am hoping to teach classes that I would have liked to have had while I was a student. My research and teaching experience is in machine learning and data science. I also have experience working with distributed systems and now work in industry for a large tech company.