====== EPGY Day 8 ======

===== Morning =====

**Question:** Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

http://www.youtube.com/watch?v=QX_oy9614HQ

  * 10:00 Tracy Ballinger, UC Santa Cruz
    * http://users.soe.ucsc.edu/~tballing/
  * 11:00 Dave Mark, Intrinsic Algorithm
    * http://www.linkedin.com/in/davemark
    * http://intrinsicalgorithm.com/IAonAI/2013/02/both-my-gdc-lectures-on-utility-theory-free-on-gdc-vault/

Cyber Stalking Assignments
  * AI Engineer - AI Scientist

Research Clusters - 20 minutes

----

**Red and Black Review**

Probability Range
  * 0 ≤ P(A) ≤ 1

Rule of Addition
  * P(A∪B) = P(A) + P(B) - P(A∩B)

Disjoint Events
Events A and B are disjoint iff
  * P(A∩B) = 0

Conditional Probability
  * P(A | B) = P(A∩B) / P(B)

>True Bayesians actually consider conditional probabilities as more basic than joint probabilities . It is easy to define P(A|B) without reference to the joint probability P(A,B). To see this note that we can rearrange the conditional probability formula to get:
>P(A|B) P(B) = P(A,B)
>but by symmetry we can also get:
>P(B|A) P(A) = P(A,B)
>It follows that:
>which is the so-called Bayes Rule.
{{:epgy:ai13:bbns0050.gif|}}

[[Bayes Problem/Solution]]

http://en.wikipedia.org/wiki/Bayesian_network

Remember: Finite State Machines? - Deterministic

Bayes Nets: http://www.idi.ntnu.no/~dingsoyr/diploma/node18.html

----

**Building a k-D tree**

Application: 3-D graphics

<code>

Algorithm BuildKDTree (S, depth) 

input: a set of points S, the current depth depth 
output: the root of a kD-tree storing S 

if S contains only one point 
    then return a leaf storing this point 
else if depth is even 
    then Split S into 2 subsets with a vertical line L through the median x-coord 
    else Split, 2 subsets with a horizontal line 

v_left <- BuildKDTree (S1, depth+1) 
v_right <- BuildKDTree (S2, depth+1) 
v <- L 
return v

</code>

  * https://dl.dropboxusercontent.com/u/3235343/Games/kdteapot.pdf
  * http://home.deib.polimi.it/matteucc/Clustering/tutorial_html/AppletH.html
  * http://www.cs.cmu.edu/~zhuxj/courseproject/knndemo/KNN.html

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**Data Classification**

Application: Separating Audio Tracks

Audio ML: http://cs229.weebly.com/index.html

----

**ConceptNet**

Application: Language

Language ML: 
  * 20Q Wordnet Conceptnet
  * Argument Champion
  * Restaurant Game

----

Decision Trees

http://weka.sourceforge.net/doc.dev/

===== Afternoon =====

  * [[Journal 8]]
  * [[Assignment 8]]
  * [[https://docs.google.com/forms/d/1-6WMYV3I5FO9hISXbFHjsYlol_F0JBSjQuHYjZGm0bw/viewform|Feedback]]