Keyword Bidding

Booking Regression

Encoding Categorical Features

Significance Time Series

Assumptions of Linear Regression

Get the top 3 highest employee salaries by department

Top Three Salaries

Last Transaction

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

Fractional Shares

Experiment Validity

Promoting Instagram

Create and write queries for health metrics for stack overflow 

Community Health Metrics

Subscription Overlap

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

Hundreds of Hypotheses

Why Do We Need Time Series Models?

Select the 2nd highest salary in the engineering department

2nd Highest Salary

Lasso vs Ridge

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

Random SQL Sample

Instagram TV Success

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

Upsell Transactions

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

Perfectly Separable

Youtube Recommendations

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

Complete Addresses

Closest SAT Scores

Type-ahead Search

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

Softmax vs Logistic

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

Over 100 Dollars

Revenue Retention

Job Recommendation

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

Detecting Firearm Sales

Raining in Seattle

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

Alphabet Sum

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

New Partner Card

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

Parents Joining Teens

Customer Orders

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

Empty Neighborhoods

Distance Traveled

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

Coefficients of Logistic Regression

First to Six

First Touch Attribution

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

Normal Distribution Sample

Random Bucketing

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

Demand Metrics

Amateur Performance

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

Prime to N

Impression Reach

Distribution of 2X - Y

Stranded Miner

Mouse Search

Netflix Retention

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

Rejection Reason

Facebook Stories

What is the difference between the Z and t tests?

Z and t-Tests

Using R Squared

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

Decreasing Comments

Rolling Bank Transactions

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

Merge Sorted Lists

Monthly Customer Report

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 

Threaded Comments

Bank Fraud Model

Download Facts

Paired Products

Cumulative Distribution

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

Comments Histogram

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

Pre-Launching Shows

Greatest Common Denominator

Manager Team Sizes

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

Employee Salaries (ETL Error)

Variable Error

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

Search Ratings

Find the missing integer from a array of consequtive integers

Find the Missing Number

Poker Pair

Changing Composer

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

Button AB Test

Find how much overlapping jobs are costing the company

Nightly Job

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

Swipe Precision

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

Random Number

500 Cards

Reducing Error Margin

Random Seed Function

One Million Rides

Missing Housing Data

Unbiased Estimator

Spam Classifier 

Post Composer Drop

Comparing Search Engines

Reconstruct the path of a trip so that the trip tickets are in order.

Scrambled Tickets

How would you analyze how the feature is performing?

Recruiting Leads

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

Title	Score	Tags	Company	Difficulty	Success This is the total number of accepted submissions divided by the total number of submissions.
Maximum Profit	3		Locked	Medium	44%	Save question Mark as completed
Maximum Common Substring	1		Locked	Medium	71%	Save question Mark as completed
Finding the Maximum Number in a List	2		Locked	Easy	67%	Save question Mark as completed

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