A Collection of Data Science Take-Home Challenges


User Referral Program



Goal


Almost all sites have a user referral program: you can invite new users to try a given product. Typically, after the new referred user completes a transaction, you get rewarded with a certain amount of money or credit to be used on the site.

The goal of this challenge is to analyze the data from a referral program and draw conclusions about its effectiveness.


Challenge Description


Company XYZ has started a new referral program on Oct, 31. Each user who refers a new user will get 10$ in credit when the new user buys something.

The program has been running for almost a month and the Growth Product Manager wants to know if it's been successful. She is very excited cause, since the referral program started, the company saw a spike in number of users and wants you to be able to give her some data she can show to her boss.

Data


We have just 1 table downloadable by clicking here.

The table is:

    referral - provides information about each transaction that happens on the site and whether the user came from the referral program or not.

Columns:

Example


    Let's check one purchase event

head (referral, 1)

Column Name Value Description
user_id 2 this is the user id
date 2015-10-03 she bought something on Oct, 3
country FR she is in France
money_spent 65 She spent 65$
is_referral 0 she didn't come via the referral program
device_id EVDCJTZMVMJDG she used a device identified by this id to make the purchase

    Let's now also check one purchase event from a user who came via the referral program

head(subset(referral,is_referral==1), 1)

Column Name Value Description
user_id 5016 this is the user
date 2015-10-31 she bought on Oct, 31
country DE she is in German
money_spent 45 it cost 45$
is_referral 1 she joined the site via another user referral
device_id OGAZARJAGCPUQ this is the device she used to complete the purchase




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