/*! 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} Q96E The negative binomial rv \({\bf{... [FREE SOLUTION] | 91影视

91影视

The negative binomial rv \({\bf{X}}\) was defined as the number of \({\bf{F}}\)鈥檚 preceding the rth \({\bf{S}}\). Let \({\bf{Y}}{\rm{ }}{\bf{5}}\) the number of trials necessary to obtain the rth \({\bf{S}}\). In the same manner in which the pmf of \({\bf{X}}\) was derived, derive the pmf of \({\bf{Y}}\)

Short Answer

Expert verified

The pmf of\(Y\)is \(p(y) = \left( {\begin{array}{*{20}{c}}{y - r + r - 1}\\{r - 1}\end{array}} \right){p^r}{(1 - p)^{y - r}},\;\;\;y \in \{ r,r + 1,r + 2, \ldots \} \)

Step by step solution

01

Concept introduction

A binomial is a mathematical expression consisting of two terms connected by a plus sign or minus sign.

02

Determine the pmf of Y

The probability mass function of the negative binomial random variable \(X\) with parameters \(r\)and \(p\), for \(x \in \mathbb{N}\), is if there are \(r\)successes with \(p\)probability of success.

\(nb(x;r,p) = \left( {\begin{array}{*{20}{c}}{x + r - 1}\\{r - 1}\end{array}} \right){p^r}{(1 - p)^x}\)

Define \(Y\)as the described random variable.

\({S_y} = \left\{ {{\bf{y}}{\rm{ trials necessary to obtain }}{r^{th}}{\rm{ success }}} \right\}\)

\({F_y} = \left\{ {{\bf{y}}{\rm{ failures preceding the }}{{\bf{r}}^{{\rm{th }}}}{\rm{ success }}} \right\}\)

\(p(y) = P(Y = y) = P\left( {{S_y}} \right)\mathop = \limits^{(1)} P\left( {{F_{y - r}}} \right)\)

\( = nb(y - r;r,p) = \left( {\begin{array}{*{20}{c}}{y - r + r - 1}\\{r - 1}\end{array}} \right){p^r}{(1 - p)^{y - r}},\;\;\;y \in \{ r,r + 1,r + 2, \ldots \} \)

If there are total of \(y\)trials necessary to obtain \({r^{{\rm{th }}}}\)success, then there must be \(y - r\)failures preceding \({r^{{\rm{th }}}}\)success.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Organisms are present in ballast water discharged from a ship according to a Poisson process with a concentration of\({\bf{10}}\)organisms/m3 (the article 鈥淐ounting at Low Concentrations: The Statistical Challenges of Verifying Ballast Water Discharge Standards鈥 (Ecological Applications) considers using the Poisson process for this purpose). a. What is the probability that one cubic meter of discharge contains at least 8 organisms? b. What is the probability that the number of organisms in\({\bf{1}}.{\bf{5}}{\rm{ }}{{\bf{m}}^3}\)of discharge exceeds its mean value by more than one standard deviation? c. For what amount of discharge would the probability of containing at least one organism be\(.{\bf{999}}\)?

A mail-order computer business has six telephone lines. Let X denote the number of lines in use at a specified time. Suppose the pmf of X is as given in the accompanying table.

X

0

1

2

3

4

5

6

p(x)

.10

.15

.20

.25

.20

.06

.04

Calculate the probability of each of the following events.

a. {at most three lines are in use}

b. {fewer than three lines are in use}

c. {at least three lines are in use}

d. {between two and five lines, inclusive, are in use}

e. {between two and four lines, inclusive, are not in use}

f. {at least four lines are not in use}

Consider a communication source that transmits packets containing digitized speech. After each transmission, the receiver sends a message indicating whether the transmission was successful or unsuccessful. If a transmission is unsuccessful, the packet is re-sent. Suppose a voice packet can be transmitted a maximum of \({\rm{10}}\) times. Assuming that the results of successive transmissions are independent of one another and that the probability of any particular transmission being successful is \({\rm{p}}\), determine the probability mass function of the rv \({\rm{X = }}\)the number of times a packet is transmitted. Then obtain an expression for the expected number of times a packet is transmitted.

A new battery鈥檚 voltage may be acceptable (A) or unacceptable (U). A certain flashlight requires two batteries, so batteries will be independently selected and tested until two acceptable ones have been found. Suppose that 90% of all batteries have acceptable voltages. Let Y denote the number of batteries that must be tested.

a. What is\(p\left( 2 \right)\), that is, \(P\left( {Y = 2} \right)\),?

b. What is\(p\left( 2 \right)\)? (Hint: There are two different outcomes that result in\(Y = 3\).)

c. To have \(Y = 5\), what must be true of the fifth battery selected? List the four outcomes for which Y = 5 and then determine\(p\left( 5 \right)\).

d. Use the pattern in your answers for parts (a)鈥(c) to obtain a general formula \(p\left( y \right)\).

Each of \({\rm{12}}\)refrigerators of a certain type has been returned to a distributor because of an audible, high-pitched, oscillating noise when the refrigerators are running. Suppose that \({\rm{7}}\) of these refrigerators have a defective compressor and the other \({\rm{5}}\) have less serious problems. If the refrigerators are examined in random order, let\({\rm{X}}\)be the number among the first \({\rm{6}}\) examined that have a defective compressor.

a. Calculate\({\rm{P(X = 4)}}\)and \(P(X拢 4)\)

b. Determine the probability that \({\rm{X}}\) exceeds its mean value by more than \({\rm{1}}\) standard deviation.

c. Consider a large shipment of \({\rm{400}}\)\({\rm{40}}\) refrigerators, of which 40 have defective compressors. If \({\rm{X}}\) is the number among \({\rm{15}}\) randomly selected refrigerators that have defective compressors, describe a less tedious way to calculate (at least approximately) P(X拢5)than to use the hypergeometric \({\rm{pmf}}\).

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.