(Problem 1: Ceiling of an Exponential)
 
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[[Category:ECE302Fall2008_ProfSanghavi]]
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[[Category:probabilities]]
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[[Category:ECE302]]
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[[Category:homework]]
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[[Category:problem solving]]
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== Instructions ==
 
== Instructions ==
 
Homework 6 can be [https://engineering.purdue.edu/ece302/homeworks/HW6FA08.pdf downloaded here] on the [https://engineering.purdue.edu/ece302/ ECE 302 course website].
 
Homework 6 can be [https://engineering.purdue.edu/ece302/homeworks/HW6FA08.pdf downloaded here] on the [https://engineering.purdue.edu/ece302/ ECE 302 course website].
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What is the PMF of <math>Y</math>? Is it one of the common random variables?  (Hint: for all <math>k</math>, find the quantity <math>P(Y > k)</math>. Then find the PMF)
 
What is the PMF of <math>Y</math>? Is it one of the common random variables?  (Hint: for all <math>k</math>, find the quantity <math>P(Y > k)</math>. Then find the PMF)
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*[[Tiffany Sukwanto 6.1_ECE302Fall2008sanghavi]]
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*[[Joshua Long 6.1_ECE302Fall2008sanghavi]]
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*[[Justin Mauck 6.1_ECE302Fall2008sanghavi]]
  
 
== Problem 2: Fair Wages ==
 
== Problem 2: Fair Wages ==
 
``I do not have problems with anyone earning above average, as long as no one earns below average." - a quote (mistakenly attributed to) Max Weber. Can such a situation occur? Justify your answer.
 
``I do not have problems with anyone earning above average, as long as no one earns below average." - a quote (mistakenly attributed to) Max Weber. Can such a situation occur? Justify your answer.
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*[[Brian Thomas 6.2_ECE302Fall2008sanghavi]] One possible solution
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*[[Gregory Pajot 6.2_ECE302Fall2008sanghavi]]
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*[[Virgil Hsieh 6.2_ECE302Fall2008sanghavi]]
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*[[Zhongtian Wang 6.2_ECE302Fall2008sanghavi]]
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*[[Michael Allen 6.2_ECE302Fall2008sanghavi]]
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*[[Christopher Wacnik 6.2_ECE302Fall2008sanghavi]]
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*[[Sahil Khosla 6.2_ECE302Fall2008sanghavi]]
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*[[AJ Hartnett 6.2 --Different answer than above!_ECE302Fall2008sanghavi]]
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*[[Jaewoo Choi 6.2_ECE302Fall2008sanghavi]]
  
 
== Problem 3: An Uncommon PDF ==
 
== Problem 3: An Uncommon PDF ==
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Let <math>Y</math> be a random variable with probability density function (PDF)
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<math>
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f_Y(v) = \left\{\begin{array}{ll}
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1 + v,& -1\leq v\leq0,\\
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v,& 0<v\leq1,\\
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0,& \mbox{otherwise}.
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\end{array}\right.</math>
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Find
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*(a) <math>P(|Y| < 1/2)</math>
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*(b) <math>P(Y > 0|Y < 1/2)</math>
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*(c) <math>E[Y]</math>.
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*[[Anand Gautam 6.3_ECE302Fall2008sanghavi]]
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*[[Nicholas Browdues 6.3_ECE302Fall2008sanghavi]]
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*[[Hamad AL Shehhi_ECE302Fall2008sanghavi]]
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*[[Ken Pesyna_ECE302Fall2008sanghavi]]
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*[[Kunal Kapoor 6.3_ECE302Fall2008sanghavi]]
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*[[Monsu Mathew 6.3_ECE302Fall2008sanghavi]]
  
 
== Problem 4: Gaussian Coordinates ==
 
== Problem 4: Gaussian Coordinates ==
A random point <math>(X,Y)</math> on a plane is chosen as follows: <math>X</math> and <math>Y</math> are chosen independently, with each one being a Gaussian random variable with zero mean and variance of 1. Let <math>D</math> be the (random) distance of the point from the center.  Find the PDF of <math>D</math>. Is <math>D</math> one of the common random variables?
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A random point <math>(X,Y)</math> on a plane is chosen as follows: <math>X</math> and <math>Y</math> are chosen independently, with each one being a Gaussian random variable with zero mean and variance of 1. Let <math>D</math> be the square of the (random) distance of the point from the center.  Find the PDF of <math>D</math>. Is <math>D</math> one of the common random variables?
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*[[Katie Pekkarinen 6.4_ECE302Fall2008sanghavi]]
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*[[Divyanshu Kamboj 6.4_ECE302Fall2008sanghavi]]
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*[[Umang Jhunjhunwala 6.4_ECE302Fall2008sanghavi]]
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*[[Spencer Mitchell 6.4_ECE302Fall2008sanghavi]]
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*[[Steven Streeter 6.4_ECE302Fall2008sanghavi]]
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----
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[[Main_Page_ECE302Fall2008sanghavi|Back to ECE302 Fall 2008 Prof. Sanghavi]]

Latest revision as of 11:57, 22 November 2011


Instructions

Homework 6 can be downloaded here on the ECE 302 course website.

Problem 1: Ceiling of an Exponential

$ X $ is an exponential random variable with paramter $ \lambda $. $ Y = \mathrm{ceil}(X) $, where the ceiling function $ \mathrm{ceil}(\cdot) $ rounds its argument up to the closest integer, i.e.:

        $ \mathrm{ceil}(a) $ = $ a $ if $ a $ is an integer
               = the smallest integer bigger than $ a $ if $ a $ is not an integer

What is the PMF of $ Y $? Is it one of the common random variables? (Hint: for all $ k $, find the quantity $ P(Y > k) $. Then find the PMF)

Problem 2: Fair Wages

``I do not have problems with anyone earning above average, as long as no one earns below average." - a quote (mistakenly attributed to) Max Weber. Can such a situation occur? Justify your answer.

Problem 3: An Uncommon PDF

Let $ Y $ be a random variable with probability density function (PDF)

$ f_Y(v) = \left\{\begin{array}{ll} 1 + v,& -1\leq v\leq0,\\ v,& 0<v\leq1,\\ 0,& \mbox{otherwise}. \end{array}\right. $

Find

  • (a) $ P(|Y| < 1/2) $
  • (b) $ P(Y > 0|Y < 1/2) $
  • (c) $ E[Y] $.

Problem 4: Gaussian Coordinates

A random point $ (X,Y) $ on a plane is chosen as follows: $ X $ and $ Y $ are chosen independently, with each one being a Gaussian random variable with zero mean and variance of 1. Let $ D $ be the square of the (random) distance of the point from the center. Find the PDF of $ D $. Is $ D $ one of the common random variables?


Back to ECE302 Fall 2008 Prof. Sanghavi

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