.. title: Engineering Probability Homework 1 due Thurs 2019-01-17
.. slug: homework01
.. date: 2019-01-10
.. tags: mathjax
.. category: homework
.. link: 
.. description: 
.. type: text


How to submit
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Submit to LMS; see details in syllabus.
   

Questions
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#. (6 pts) One of the hardest problems is forming an appropriate
   probability model. E.g., suppose you're working for Verizon
   deciding how much data capacity your network will need once it
   starts selling the iphone.  Suppose that you know that each
   customer will use 5GB/month.  Since a month has about 2.5M seconds,
   does that mean that your network will need to provide only 2KB/s
   per customer?  What might be wrong with this model?  How might you
   make it better?  (This is an open-ended question; any reasonable
   answer that shows creativity gets full points.)

#. (3 pts) One hard problem with statistics is how they should be
   interpreted.  For example, mental health care professionals observe
   that young men with schizophrenia usually smoke pot (marijuana).
   Assuming for the sake of argument that this correlation is real,
   does this mean that pot smoking causes schizophrenia?

   *Historical note:* In 1974, the question of whether cigarette smoking causes lung cancer was answered by forcing some dogs in a lab to smoke and observing that they got cancer more than otherwise identical dogs not forced to smoke.

   The tobacco companies were maintaining that the strong correlation between smoking and lung cancer (1/4 of smokers died from cancer) did not demonstrate a causal relation.  Maybe there was a common cause for both a desire to smoke and a likelihood to later get cancer.  These experiments refuted that claim.

   `Mary Beith, the journalist who broke the 'smoking beagles' story <https://www.theguardian.com/media/greenslade/2012/may/20/thepeople-investigative-journalism>`_

#. (6 pts) Do exercise 1.3 in the text on page 19.

#. (6 pts) Do exercise 1.6 on page 19.

#. (6 pts) Do exercise 1.11 on page 20.

Total: 27 pts.

