Chapter 9: Problem 15
A coin having probability \(p=\frac{2}{3}\) of coming up heads is flipped 6 times. Compute the entropy of the outcome of this experiment.
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 9: Problem 15
A coin having probability \(p=\frac{2}{3}\) of coming up heads is flipped 6 times. Compute the entropy of the outcome of this experiment.
All the tools & learning materials you need for study success - in one app.
Get started for free
Show that, for any discrete random variable \(X\) and function \(f\) $$ H(f(X)) \leq H(X) $$
Suppose that whether it rains tomorrow depends on past weather conditions only through the last 2 days. Specifically, suppose that if it has rained yesterday and today, then it will rain tomorrow with probability \(.8 ;\) if it rained yesterday but not today, then it will rain tomorrow with probability \(.3 ;\) if it rained today but not yesterday, then it will rain tomorrow with probability \(.4 ;\) and if it has not rained either yesterday or today, then it will rain tomorrow with probability. \(2 .\) What proportion of days does it rain?
A transition probability matrix is said to be doubly stochastic if $$ \sum_{i=0}^{M} P_{i j}=1 $$ for all states \(j=0,1, \ldots, M .\) Show that such a Markov chain is ergodic, then \(\prod_{j}=1 /(M+1), j=\) \(0,1, \ldots, M\).
Prove that if \(X\) can take on any of \(n\) possible values with respective probabilities \(P_{1}, \ldots, P_{n},\) then \(H(X)\) is maximized when \(P_{i}=1 / n, i=1, \ldots, n .\) What is \(H(X)\) equal to in this case?
A pair of fair dice is rolled. Let $$ X=\left\\{\begin{array}{ll} 1 & \text { if the sum of the dice is } 6 \\ 0 & \text { otherwise } \end{array}\right. $$ and let \(Y\) equal the value of the first die. Compute (a) \(H(Y),(b) H_{Y}(X),\) and \((c) H(X, Y)\).
What do you think about this solution?
We value your feedback to improve our textbook solutions.