instructions
Assignment 2 Part 2
Winter 2018
Remember: This is an individual assignment.
Anything that looks like work copied from another student will be submitted to the fraud committee,
so do not share any written versions of your work with anyone.
You may discuss the general concepts of this assignment with class mates.
This document is provided for in-class use only. Do not share with individuals outside this class and do
not post it on the internet. I appreciate your cooperation on this matter.
Questions
Many internet apps, services and advertising rely on people clicking on links. Here are some questions
relating to whether people will click on a link or not. Assume a basic scenario where the probability of
someone clicking a link is 0.019. (This seems to be a generally realistic click-through rate).
For all the questions below, briefly identify what information is given, what approach you are using and
why, what you are looking for, and then show the calculations.
You and three of your friends, Mo, Chen and Sam have seen the link.
Q1 What is the probability that none of you have clicked on the link?
Q2 What is the probability that you and Chen clicked the link?
Q3 What is the probability that at least two of your group of friends have clicked the link?
A company is working on its marketing campaign. Pre-tests show that it is reasonable to assume the
same probability that someone who sees the link will click on it of 0.019. This link is relevant to a broad
audience, so the company contracts with an internet platform that promises to show the link to 10,000
people.
Q4 What is the probability that more than 215 will click on the link?
The company is also interested in how its customers feel about the links it provides. Based on a recent
survey, the company believes 25% of its 20,000 customers appreciate the links the company provides.
Q5 If the company sends a certain link to 5,000 of its customers, what is the probability that fewer than
1200 of those customers will appreciate the link?