10-601 Lecture Notes - Lecture 1: Activity Tracker, Global Positioning System, Binary Tree

128 views3 pages
Published on 1 Mar 2019
Recitation 1
CMU 10-601: Machine Learning (Spring 2019)
Friday, Jan 18th, 2019
1 Probability and Statistics
1. Two events, A and B, are considered disjoint (mutually exclusive). P(A) = 0.5, P(B)
= 0.5.
What is the P(AB) ?
What is the P(AB) ?
What is the P(A|B) ?
2. Now, instead, the two events A and B are not disjoint, but they are independent.
What is the P(AB) ?
What is the P(AB) ?
What is the P(A|B) ?
3. A student is looking at her activity tracker (Fitbit/Apple Watch) data and she notices
that she seems to sleep better on days that she exercises. They observe the following:
Exercise Good Sleep Probability
Yes Yes 0.3
Yes No 0.2
No No 0.4
No Yes 0.1
What is the P(GoodSleep =Y es|Exercise =Y es) ?
Why doesn’t P(GoodSleep =Y es Exercise =Y es) = P(GoodSleep =Y es)·
P(Exercise =Y es) ?
The student merges her activity tracker data with her food logs and finds that
the P(Eatwell =Y es|Exercise =Y es GoodSleep =Y es) is 0.25. What is the
probability of all three happening on the same day?
4. What is the E[X] where X is a single roll of a fair 6-sided dice (S = {1,2,3,4,5,6})? What
is the Var[X]?
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Notes+

Unlimited access to class notes and textbook notes.

YearlyBest Value
75% OFF
$8 USD/m
$30 USD/m
You will be charged $96 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.