A First Course in Probability (10th Edition)
A First Course in Probability (10th Edition)
10th Edition
ISBN: 9780134753119
Author: Sheldon Ross
Publisher: PEARSON
Bartleby Related Questions Icon

Related questions

Question
Once an individual has been infected with a certain disease, let \( X \) represent the time (days) that elapses before the individual becomes infectious. An article proposes a Weibull distribution with \( \alpha = 2.6 \), \( \beta = 1.2 \), and \( \gamma = 0.5 \). [Hint: The two-parameter Weibull distribution can be generalized by introducing a third parameter \( \gamma \), called a threshold or location parameter: replace \( x \) in the equation below,

\[
f(x; \, \alpha, \, \beta) = 
\begin{cases} 
\frac{\alpha}{\beta^\alpha}x^{\alpha - 1}e^{-(x/\beta)^\alpha} & x \geq 0 \\
0 & x < 0 
\end{cases}
\]

by \( x - \gamma \) and \( x \geq 0 \) by \( x \geq \gamma \).]

(a) Calculate \( P(1 < X < 2) \). (Round your answer to four decimal places.)

\[ \boxed{\phantom{1234}} \]

(b) Calculate \( P(X > 1.5) \). (Round your answer to four decimal places.)

\[ \boxed{\phantom{1234}} \]

(c) What is the 90th percentile of the distribution? (Round your answer to three decimal places.)

\(\boxed{\phantom{1234}}\) days

(d) What are the mean and standard deviation of \( X \)? (Round your answers to three decimal places.)

Mean: \(\boxed{\phantom{1234}}\) days

Standard Deviation: \(\boxed{\phantom{1234}}\) days
expand button
Transcribed Image Text:Once an individual has been infected with a certain disease, let \( X \) represent the time (days) that elapses before the individual becomes infectious. An article proposes a Weibull distribution with \( \alpha = 2.6 \), \( \beta = 1.2 \), and \( \gamma = 0.5 \). [Hint: The two-parameter Weibull distribution can be generalized by introducing a third parameter \( \gamma \), called a threshold or location parameter: replace \( x \) in the equation below, \[ f(x; \, \alpha, \, \beta) = \begin{cases} \frac{\alpha}{\beta^\alpha}x^{\alpha - 1}e^{-(x/\beta)^\alpha} & x \geq 0 \\ 0 & x < 0 \end{cases} \] by \( x - \gamma \) and \( x \geq 0 \) by \( x \geq \gamma \).] (a) Calculate \( P(1 < X < 2) \). (Round your answer to four decimal places.) \[ \boxed{\phantom{1234}} \] (b) Calculate \( P(X > 1.5) \). (Round your answer to four decimal places.) \[ \boxed{\phantom{1234}} \] (c) What is the 90th percentile of the distribution? (Round your answer to three decimal places.) \(\boxed{\phantom{1234}}\) days (d) What are the mean and standard deviation of \( X \)? (Round your answers to three decimal places.) Mean: \(\boxed{\phantom{1234}}\) days Standard Deviation: \(\boxed{\phantom{1234}}\) days
Expert Solution
Check Mark
Knowledge Booster
Background pattern image
Similar questions
Recommended textbooks for you
Text book image
A First Course in Probability (10th Edition)
Probability
ISBN:9780134753119
Author:Sheldon Ross
Publisher:PEARSON
Text book image
A First Course in Probability
Probability
ISBN:9780321794772
Author:Sheldon Ross
Publisher:PEARSON