Variable Error

Encoding Categorical Features

Write a query to select the top 3 departments with at least ten employees and rank them according to the percentage of their employees making over 100K in salary.

Employee Salaries

Estimating D

What are the logistic and softmax functions? What is the difference between the two?

Softmax vs Logistic

Coefficients of Logistic Regression

Paired Products

Experiment Validity

Lasso vs Ridge

Why Do We Need Time Series Models?

Subscription Overlap

You are testing hundreds of hypotheses with many t-tests. What considerations should be made?

Hundreds of Hypotheses

Random Bucketing

Job Recommendation

Revenue Retention

Raining in Seattle

Write a function to create a single dataframe with complete addresses in the format of street, city, state, zip code.

Complete Addresses

How do we give each rejected applicant a reason why they got rejected?

Rejection Reason

Changing Composer

Amateur Performance

Impression Reach

This problem involves finding the first non-repeating character in a given string. The solution involves iterating over the string and keeping track of the frequency of each character. The first character that has a frequency of 1 is the first non-repeating character.

Find the First Non-Repeating Character in a String

Compute Deviation

Greatest Common Denominator

We’re nearing the end of the quarter and are missing revenue expectations by 10%. An executive asks the email marketing person to send out a huge email blast to your entire customer list asking them to buy more products.  Is this a good idea? Why or why not?

Email Blast

Write a function friendship_timeline to generate an output that lists the pairs of friends with their corresponding timestamps of the friendship beginning and then the timestamp of the friendship ending. 

Friendship Timeline

How would you investigate a decline in the average number of comments per user?

Decreasing Comments

Write a SQL query to create a histogram of the number of comments per user in the month of January 2020.

Comments Histogram

Customer Orders

Download Facts

First Touch Attribution

Instagram TV Success

Significance Time Series

Assumptions of Linear Regression

Booking Regression

Create and write queries for health metrics for stack overflow 

Community Health Metrics

Say you are given a dataset of perfectly linearly separable data. What would happen when you run logistic regression?

Perfectly Separable

How would you identify supply and demand mismatch in a ride sharing market place?

Demand Metrics

Write a function to return a dataframe containing every transaction with a total value of over $100.

Over 100 Dollars

Youtube Recommendations

How would you build a model to detect if a post on a marketplace is talking about selling a gun?

Detecting Firearm Sales

Alphabet Sum

Given a stream of numbers, select a random number from the stream.

Random Number

Distribution of 2X - Y

Facebook Stories

Given that it is raining today and that it rained yesterday, write a function to calculate the probability that it will rain on the nth day after today.

Rain in N Days

New Partner Card

Stranded Miner

Mouse Search

How would you find out if an increase in user conversion rates after a new email journey is casual or just part of a wider trend?

Causal Email Journey 

Parents Joining Teens

How do we go about selecting the best 10,000 customers for the pre-launch?

Pre-Launching Shows

Given two sorted lists, write a function to merge them into one sorted list.

Merge Sorted Lists

First to Six

Rolling Bank Transactions

Select the 2nd highest salary in the engineering department

2nd Highest Salary

Write a query to get the number of customers that were upsold

Upsell Transactions

Find the missing integer from a array of consequtive integers

Find the Missing Number

Write a query to get the current salary for each employee after an ETL error.

Employee Salaries (ETL Error)

Fractional Shares

Last Transaction

Write a query that returns all neighborhoods that have 0 users.

Empty Neighborhoods

Write a query to randomly sample a row from a big table.

Random SQL Sample

Closest SAT Scores

Monthly Customer Report

Given an integer N, write a function that returns all of the prime numbers up to N

Prime to N

What is the difference between the Z and t tests?

Z and t-Tests

Cumulative Distribution

Distance Traveled

Promoting Instagram

Write a function to select only the rows where the student's favorite color is green or red and their grade is above 90.

Good Grades and Favorite Colors

Threaded Comments

Write a SQL query to find the average number of right swipes for different ranking algorithms.

Swipe Precision

Bank Fraud Model

Poker Pair

Get the top 3 highest employee salaries by department

Top Three Salaries

Manager Team Sizes

Using R Squared

Netflix Retention

Type-ahead Search

Write a query to create a metric that can validate and rank the queries by their search result precision.

Search Ratings

Button AB Test

Keyword Bidding

A new airline came out as the fastest average boarding times compared to other airlines.  What factors could have biased this result and what would you look into?

Boarding Times Bias

Write a function to get a sample from a standard normal distribution.

Normal Distribution Sample

Find how much overlapping jobs are costing the company

Nightly Job

Design a data warehouse for a new online retailer

Retailer Data Warehouse

What statistical test could you use to determine which of two parcel types is better to use, given how often they are damaged?

Different Parcel Effectiveness

Find the total salary of slacking employees.

Slacking Employees Salaries

One Million Rides

Missing Housing Data

Biased five out of six

Post Composer Drop

Determine whether there exists a permutation of an input string that is a palindrome.

Permutation Palindrome

Determine the cause of the drop in capital approval rates.

Approval Drop

Write a function to get a sample from a Bernoulli trial.

Bernoulli Sample

Time on FB Distribution

Given a list of integers, and an integer N, write a function to find all combinations that sum to the value N.

Sum to N

Declining Applicants

Ad raters are careful or lazy with some probability.

Barclays Interview Questions

Sorry, there are no questions found.

Quick filters

Study Plan

Top Companies

Question Tags