A First Course in Probability (10th Edition)
A First Course in Probability (10th Edition)
10th Edition
ISBN: 9780134753119
Author: Sheldon Ross
Publisher: PEARSON
bartleby

Videos

Textbook Question
Book Icon
Chapter 10, Problem 10.1P

The following algorithm will generate a random permutation of the elements 1,2, ..., n. It is somewhat faster than the one presented in Example 1a, but is such that no position is fixed until the algorithm ends. In this algorithm, P ( i ) can be interpreted as the element in position i.

Step 1. Set k = 1

Step 2. Set P ( 1 ) = 1 .

Step 3. If k = n , stop otherwise, let k = k + 1 .

Step 4. Generate a random number U and let P ( k ) = P ( [ k U ] + 1 ) P ( [ k U ] ÷ 1 )   = k

Go to step 3.

a. Explain in words what the algorithm is doing.

b. Show that at iteration k—that is. when the value of P(k) Is initially set—

P(1), P(2), ..., P(k) is a random permutation of 1, 2, ..., k.

Hint: Use induction and argue that P k { i 1 , i 2 ... , i j 1 , k , i j , ... , i k 2 , i } = P k 1 { i 1 , i 2 ... , i j 1 , k , i j , ... , i k 2 } 1 k = 1 k !  by the induction hypothesis

(a)

Expert Solution
Check Mark
To determine

To find: the explanation that the algorithm is doing.

Explanation of Solution

Given:

Some steps of algorithm are given.

The algorithm starts by initially putting k=1 thus it sets p(1)=1 .

Then, until K=M it increases the value of K by one after each iteration. It generates a random number U and replaces p(k) by p([ku]+1) . Then, it puts p([ku]+1)=k . Then, it goes again to step 3.

This algorithm start by putting p(1)=1 , but it does not exclude this value in next interation the value of p(1) can change in any subsequent iteration. Thus, no position is fixed until the algorithm ends.

Therefore, therequired explanation is shown above.

(b)

Expert Solution
Check Mark
To determine

To prove:that the set p(1),p(2),.....,p(k) which is a random permutation of 1,2,....,k .

Explanation of Solution

Given:

It is given that pk{i1,i2,......,ik}=pk1{i1,i2,.....,ik1}×p{ik} .

As it is given that the condition pk{i1,i2,......,ik}=pk1{i1,i2,.....,ik1}×p{ik} .

It is known that;

  p{ik}=1total sample space=1k

Then, the given condition becomes;

  pk{i1,i2,......,ik}=pk1{i1,i2,.....,ik1}×1k

Similarly,

  pk{i1,i2,......,ik}=1k×1k1×.....11=1k!

This proves that at iteration k can be defined as p(1),p(2),.....,p(k) which is a random permutation of 1,2,....,k .

Therefore, the required identity has been proved.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
A warranty is written on a product worth $10,000 so that the buyer is given $8000 if it fails in the first year, $6000 if it fails in the second, and zero after that. The probability of the product’s failing in a year is 0.15; failures are independent of those of other years. What is the expected value of the warranty?
The probability that a machine produces a defective item is 0.02. Each item is checked as it is produced. Assume that these are independent trials, and compute the probability that at least 90 items must be checked to find one that is defective.
Bowl A contains 3 white and 2 red chips, bowl B contains 4 white and 4 red chips, and bowl C contains 4 white and 5 red chips. The probabilities of selecting bowls A, B, and C are 1/3, 1/6, and 1/2 respectively. One chip is selected at random. Given that a white chip is selected what is the probability that it came from bowl C. Round your answer to three decimal places.

Additional Math Textbook Solutions

Find more solutions based on key concepts
Knowledge Booster
Background pattern image
Probability
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, probability and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Linear Algebra: A Modern Introduction
Algebra
ISBN:9781285463247
Author:David Poole
Publisher:Cengage Learning
Text book image
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Text book image
Elements Of Modern Algebra
Algebra
ISBN:9781285463230
Author:Gilbert, Linda, Jimmie
Publisher:Cengage Learning,
Graph Theory: Euler Paths and Euler Circuits; Author: Mathispower4u;https://www.youtube.com/watch?v=5M-m62qTR-s;License: Standard YouTube License, CC-BY
WALK,TRIAL,CIRCUIT,PATH,CYCLE IN GRAPH THEORY; Author: DIVVELA SRINIVASA RAO;https://www.youtube.com/watch?v=iYVltZtnAik;License: Standard YouTube License, CC-BY