Let Y~ Exp(A). Given that Y = y, let X~ Poisson(y). Find the mean and variance of X. Hint. Find E[XY] and E[X2Y] directly from knowledge of Poisson moments, and then E[X] and E[X2] from knowledge of exponential moments.

Answers

Answer 1

Given that $Y\sim\text{Exp}(A)$, the probability density function of $Y$ is $f_Y(y)=Ae^{-Ay}$ for $y\geq 0$.

Let $X\sim\text{Poisson}(Y)$. Then, the conditional probability

mass function of $X$ given $Y=y$ is

P(X=k∣Y=y)=e−yykk!,k=0,1,2,…

To find the mean and variance of $X$, we first find $E[XY]$ and $E[X^2Y]$.

\begin{align*}

E[XY] &= \int_{0}^{\infty} E[XY|Y=y]f_Y(y)dy \

&= \int_{0}^{\infty} E[Xy]Ae^{-Ay}dy \

&= \int_{0}^{\infty} ye^{-y}\sum_{k=0}^{\infty}k\frac{y^k}{k!}Ae^{-Ay}dy \

&= \int_{0}^{\infty} ye^{-y}\sum_{k=1}^{\infty}\frac{y^{k-1}}{(k-1)!}Ae^{-Ay}dy \

&= A\int_{0}^{\infty} y\sum_{k=1}^{\infty}\frac{(Ay)^{k-1}}{(k-1)!}e^{-Ay}e^{-y}dy \ &= A\int_{0}^{\infty} y\sum_{k=0}^{\infty}\frac{(Ay)^{k}}{k!}e^{-Ay}e^{-y}dy \

&= A\int_{0}^{\infty} ye^{-(A+1)y}\sum_{k=0}^{\infty}\frac{(Ay)^{k}}{k!}dy \

&= A\int_{0}^{\infty} ye^{-(A+1)y}e^{Ay}dy \

&= \frac{A}{(A+1)^2} \end{align*}

Similarly, we can find $E[X^2Y]$ as:

\begin{align*}

E[X^2Y] &= \int_{0}^{\infty} E[X^2Y|Y=y]f_Y(y)dy \

&= \int_{0}^{\infty} E[X^2y]Ae^{-Ay}dy \

&= \int_{0}^{\infty} y^2e^{-y}\sum_{k=0}^{\infty}k^2\frac{y^k}{k!}Ae^{-Ay}dy \

&= \int_{0}^{\infty} y^2e^{-y}\sum_{k=2}^{\infty}\frac{k(k-1)y^{k-2}}{(k-2)!}Ae^{-Ay}dy \

&= A\int_{0}^{\infty} y^2\sum_{k=0}^{\infty}\frac{(Ay)^{k}}{k!}e^{-Ay}e^{-y}dy \ &= A\int_{0}^{\infty} y^2e^{-(A+1)y}\sum_{k=0}^{\infty}\frac{(Ay)^{k}}{k!}dy \

&= A\int_{0}^{\

For such more questions on Probability density function:

https://brainly.com/question/28705601

#SPJ11


Related Questions

What is 631.051 as a fraction
sorry if that doesnt make sense.

Answers

Answer:

631 and 51/1000

Step-by-step explanation:

The altitude of an airplane is decreasing at a rate of 40 feet per second. What is the change in altitude of the airplane over a period of 20 seconds?

Answers

Answer:

Step-by-step explanation:

-40t

-40(20)

-800 ft

a quadratic polynomial the sum of whose zeros is -3 and product is -10​

Answers

Answer:

2 and -5 i think

Step-by-step explanation:

Josie makes invitations for her aunt's paper company. Of all the invitations Josie makes, 15/21 are children's party invitations. Of those invitations, 3/5 have an animal on them. What fraction of the invitations Josie makes are children's party invitations with an animal on them?

Answers

Answer:

the fraction of the invitations considered to be an animal on them is [tex]\frac{3}{7}[/tex]

Step-by-step explanation:

The computation of the fraction of the invitations considered to be an animal on them is shown below:

= Children party invitations × animal on them

[tex]= \frac{15}{21} \times \frac{3}{5}\\\\= \frac{3}{7}[/tex]

Hence, the fraction of the invitations considered to be an animal on them is [tex]\frac{3}{7}[/tex]

Smiths bike shop rents bikes for $10
plus $4 per hour. Anita paid $22 to
rent a bike. How many hours did
she rent the bike for? Write an
equation to represent this situation
and then solve.

Answers

10+(4x3)= $22 (How much she rent the bike for)

What scale factor was applied to the first rectangle to get the resulting image?

Answers

Answer: Another way to look at it is that the rectangle was reduced in a factor of 5 (1/0.2=5)

don't forget to drop a heart hope it helped

Step-by-step explanation:

Answer: 1/0.2=5

Step-by-step explanation:

I hope this helps if you guys need a reach out to me :)

tysmmmmmmmmmmmmmmmmmmmmmm

Answers

Answer:

The answer is 10

Step-by-step explanation:

To get this you will make the improper fraction into a fraction and then turn that into decimal form

[tex]4 \frac{1}{8} = 4[/tex]

and

[tex]5 \frac{6}{10} = 6[/tex]

That is how you find the estimated answer

Hope this Helped

que volumen ocupará 600 g de agua?

Answers

Answer:

Step-by-step explanation:

600 ml

89+67
berapakah jawapan nya​

Answers

Answer:

156

Step-by-step explanation

fgcfgvhvcfgvxxbbhhcx

Answer:

Jawapan kepada 89 + 67 = 156

If 95% of students are coming to school tomorrow, what is the complement?

Question 5 options:

A. 95%


B. 100%


C. 1%


D. 5%

Answers

Answer:

d

Step-by-step explanation:

can you help me with this question According to Frost in his poem "The Road Not Taken," what kind of difference did taking one road over another road make? A. It made a good difference, B. It made a bad diference, c. Frost does not say

Answer:

the answer is d

Step-by-step explanation:

it only takes 5% to get to 100%

E = MV^2 ÷ 2 + mgh, Make V Subject of the formula​

Answers

Answer:

[tex] \red{ \bold{ V = \sqrt{\frac{2(E - mgh)}{M}}}}[/tex]

Step-by-step explanation:

[tex]E = MV^2 ÷ 2 + mgh \\ \\ E - mgh = MV^2 ÷ 2 \\ \\ 2(E - mgh)= MV^2 \\ \\ \frac{2(E - mgh)}{M}=V^2 \\ \\ \sqrt{\frac{2(E - mgh)}{M}} = V \\ \\ \red{ \bold{ V = \sqrt{\frac{2(E - mgh)}{M}}}}[/tex]

Can someone please tell me what is the solution

Answers

Answer:

[tex] \frac{1}{4} \tan {}^{4}(x) + c[/tex]

4. Six numbers are shown.
1.25, -1.5, -0.75,
34,
2 6/8,
5/4
Place each number in its correct location on the number line.

Answers

Step-by-step explanation:

sorry i couldn't solve the last and the last second one

Was it helpful?

comment down

If there is any kind of suspicious mistake

then sorry

How do you solve for x and y?

Answers

Answer:

x = 100, y = 50

Step-by-step explanation:

Make a system of equations:

First, you know that x + y degrees and 30 degrees are on a line together, they add up to 180 degrees:

x + y + 30 = 180

x + y = 150

Next, the interior angles of a triangle always add up to 180 degrees, and since 2y, x/2, and 30 are all the angles in a triangle, you have:

2y + x/2 + 30 = 180

x/2 + 2y = 150

Now, all you have to do is solve the system of equations.

To start, multiply the second equation by 2 to get rid of the fraction:

x + 4y = 300

Then, you can subtract the two equations:

x + 4y = 300

- (x + y = 150)

3y = 150

divide both sides by 3

y = 50

substitute y = 50 into the equation x + y = 150:

x + 50 = 150

x = 100

pls help ty !
question is in the pic

Answers

Yes the answer is correct because you are adding 2 perfect squares and you get the same answer !

Answer:

He is not correct

Please help me 15 points it’s worth it please help me on this question

Answers

Answer:

last answer

Step-by-step explanation:

10.
Write a rule for the linear function in the graph.

A. y = 4/5x + 2

B. y = -5x - 2

C. y = 5/4x - 2

D. y = -4/5x + 2

Answers

Answer:

D. y = -4/5x + 2

Step-by-step explanation:

Graph the line using the slope and y-intercept, or two points.

Slope:  

4

5

y-intercept:  

(

0

,

2

)

x

y

0

2

5

2

0

Due in 20 please help

The polygons are similar. Find the values of
the variables. Write an equation and solve,
showing ALL the work.

Answers

It tells you they are similar. This means the angles are the same, and the sides are proportionate.

Look at the 12 and 4 at the very bottom. This tells you the ratio of the sides. Since 12 / 4 = 3, you can find y with 2 * 3 which is 6.

From that, you also know that 3z = 3y - 2. Substitute the value of y in and you can find z.

Corresponding angles are exactly the same. which means, (3x)° = 100°

You should get x = 33 1/3, y = 6, z = 5 1/3

Hi! PLS HELP ITS 30 POINTS!! Thanks!
A soda bottle holds 1.5 liters of soda. How many milliliters does the bottle hold?

15 millimeters
150 millimeters
1,500 millimeters
15,000 millimeters
Pls help!
Imma report u if its something off the topic!
Thanks again!
(its not b i tried it and got it wrong!! )

Answers

Answer:

1,500 millimeters

Step-by-step explanation:

1 litre = 1000 millilitre.

Try 1,500.

What is the scientific notation for .000472

Answers

Answer:

The scientific notation for 0.000472 is 4.72 * [tex]10^{-4}[/tex].

solve each system of eaquasions x+4y=4 -x+2y=8​

Answers

x + 4y = 4
-x + 2y = 8


x + 4y - x + 2y = 4 + 8

6y = 12

y = 2


x + 4(2) = 4
x + 8 = 4
x = -4

(x,y)
(-4,2)

Answer:

(-4, 2)

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right  

Distributive Property

Equality Properties

Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of Equality

Algebra I

Terms/CoefficientsCoordinates (x, y)Solving systems of equations using systems

Step-by-step explanation:

Step 1: Define Systems

x + 4y = 4

-x + 2y = 8

Step 2: Rewrite Systems

x + 4y = 4

[Subtraction Property of Equality] Subtract 4y on both sides:                    x = 4 - 4y

Step 3: Redefine Systems

x = 4 - 4y

-x + 2y = 8

Step 4: Solve for y

Substitution

Substitute in x:                                                                                                 -(4 - 4y) + 2y = 8[Distributive Property] Distribute negative:                                                   -4 + 4y + 2y = 8Combine like terms:                                                                                        -4 + 6y = 8[Addition Property of Equality] Add 4 on both sides:                                    6y = 12[Division Property of Equality] Divide 6 on both sides:                                y = 2

Step 5: Solve for x

Define original equation:                                                                                x + 4y = 4Substitute in y:                                                                                                 x + 4(2) = 4Multiply:                                                                                                            x + 8 = 4[Subtraction Property of Equality] Subtract 8 on both sides:                       x = -4

can someone please help me u can just do 5 and explain please


¿Puede alguien ayudarme? Puedes hacer 5 y explicar por favor.

Answers

Answer:

i only can explain until number 7

i am sorry

maybe that help you

Well I need the help in this last question I will mark brain list if you got it right

Answers

Answer:

6x−11y+15

Step-by-step explanation:

Distribute the Negative Sign:

=5x−6y+7+−1(−x+5y−8)

=5x+−6y+7+−1(−x)+−1(5y)+(−1)(−8)

=5x+−6y+7+x+−5y+8

Combine Like Terms:

=5x+−6y+7+x+−5y+8

=(5x+x)+(−6y+−5y)+(7+8)

=6x+−11y+15

Answer:

6x−11y+15

I hope I helped!!

(5x-6y+7) -(-x +5y -8)
=5x-6y+7+x-5y+8
=6x -11y +15
Hope it helps you (^_^)

Delia takes out a loan to buy a car for $18,000 with an interest rate of 6.5%. The amount of interest Delia will have to pay is $4,680. Write and solve an equation to determine the number of months her loan is for. Show all of your work and explain how you got your number of months.

Answers

Answer:

Delia pays $4,680 in 4 months

Step-by-step explanation:

Equation:

18,000 * 6.5% = 1170

4680 ÷ 4 = 1170

So, the answer is 4 months this is the equation.

Hope this helps! :)

An account earns simple interest.
$600 at 5% for 2 years

a.Find the interest earned.
$___

b.Find the balance of the account.
$___



Please answer and give an explanation with your response. I will mark the correct and quickest answer BRAINLIEST!!!

Answers

Answer:

600×100/5×2=

6\10=3/5

Answer:

A is $60

B is $660

Step-by-step explanation:

For A, you move the decimal in 5% 2 over so it is 0.05. You then multiply 0.05 by 600, multiply that answer by 2, and you'll get $60.

Sorry I'm not sure how to do B, I looked up the answer to that one.

Christine has her own dog -walking business. She Charges her customers $20 per day to walk their day

Answers

Answer:

y= money made

x = amount of dogs walked

equation- y = 20x

for the table name # of dogs walked on the right and money earned on the left.

for the left put 1 2 3 4 5 6 7 and 8

1 goes with 20

2 goes with 40

3 with 60

4 with 80

5 with 100

6 with 120

7 with 140 and

8 with 160

Step-by-step explanation:

Find the volume of the figure.
10 cm
8 cm
10 cm
14 cm
10 cm
8 cm
cubic centimeters

Answers

Answer:

60 cm³

Step-by-step explanation:

Step-by-step explanation:

=896000 is the answer

method -10x8x10x14x10x8

️️

Solve by elimination:
9x + 4y = 97
9x + 6y = 123
14
15'
B (5, 13)
(13,5)
D (1, 22)

Answers

Answer:

B (5, 13)

Step-by-step explanation:

9x + 4y = 97

9x + 6y = 123

To solve by elimination, we want to eliminate a variable. To do this, we must make one variable cancel out.

First, we can see that both equations have 9x. To cancel out x, we must make one of the 9x's negative. To do this, multiply each term in the equation by -1.

-1(9x + 6y = 123)

-9x - 6y = -123

This is one of your equations. Set it up with your other given equation.

9x + 4y = 97

-9x - 6y = -123

Imagine this is one equation. Since every term is negative, you will be subtracting each term.

9x + 4y = 97

-9x - 6y = -123

___________

0x -2y = -26

-2y = -26

To isolate y further, divide both sides by -2.

y = 13

Now, to find x, plug y back into one of the original equations.

9x + 4(13) = 97

Multiply.

9x + 52 = 97

Subtract.

9x = 45

Divide.

x = 5

Check your answer by plugging both variables into the equation you have not used yet.

-9(5) - 6(13) = -123

-45 - 78 = -123

-123 = -123

Your answer is correct!

(5, 13)

Hope this helps!

GIVING BRAINLIEST!!!

Answers

Answer:

i think its 78.5 but the answers not on there the closest one there to it is 76.5 so just put that one

Step-by-step explanation:

Triangles are similar Find the value of x.
Please help Thank you in advanced ​

Answers

Answer:

x=36

Step-by-step explanation:

14/42=12/x

14x=12(42)

14x=504

x=36

Other Questions
Which of the following is true about the molecular structure of voltage-gated sodium channels?A.They are single polypetide chains with 4-6 heterologous subunits (alpha helices) and a voltage sensor on the S5 segmentB.The subunits are single polypeptide chains organized in four homologous domains, which each contain six transmembrane alpha helices (S1S6) and an additional pore loop located between the S5 and S6 segmentsC.The subunits are comprised of 4 heterologous subunits that are connected by a pore loop located between the S5 and S6 segments.D.The pore-forming subunit is accompanied by 1 or 2 -subunits which modulate channel gating and localization of the channel in the membrane.E.The presence of a -subunit means that the channel has an inactivation gate, which blocks the channels according to a "ball-and-chain" model. Channels without -subunits have properties of "persistent sodium currents" that do not inactivateF.Answers B and D are true You are comparing financial aid offers. One has offered you $8,000 in grants; $5,000 in scholarships; $3,000 in work study; and $14,000 in loans. How much of this is considered "free money"? $8,000 $5,000 $13,000 $14,000 $16,000 use spherical coordinates to evaluate the triple integral -2 to 2, 0 to sqrt 4-y^2, -sqrt 4 - x^2 - y^2 Impulse involves the time that a force acts, whereas work involves the Select one: O a. acceleration that a force produces. O b. distance that a force acts. O c. time and distance that a force acts. O d. distance and velocity that a force acts russian national guard, about 300,000 troops at the presidents personal disposal, was created for the specific purpose of putting down mass revolts in russia. when was the guard created? in the contingency table we have (r - 1) times (c - 1) degrees of freedom (r is the number of rows and c is the number of columns). true false Which of the following statements is most consistent with coaching (as opposed to counseling)?A) "I'd like to see you work on your attitude. You are often too pessimistic."B) "Would you like to talk with me about the interpersonal conflict you are having with your supervisor?"C) "Let's plan some time tomorrow for me to walk you through the audit process. I think I can help you see where you are making mistakes."D) "I'm concerned that you seem to be growing less committed to the mission of our organization. Why don't you spend a little more time with our customers so that you can reignite your passion?" Which of these solutions is a buffer? Explain your answer. i. 0.50 M HCI + 0.50 M HCIO4ii. 0.10 M HCl + 0.20 M KOH iii. 0.65 M CH3NH2 +0.50 M CH3NH3NO3 iv. 0.80 M NaOH +0.75 M NH3 v. 1.5 M CH3COOH +0.75 M HCI which element of interpersonal attraction is most important for initial attraction than for maintenance attraction? HALP FAST AND WILL MARK BRAINIEST TO THE FIRST PERSON a scientist is interested in finding out the effect of soil quality on crop yield. would an experimental or observational study design be more appropriate? If American tourist increase visits to japan, the supply US dollars will _____ and the demand for Japanese yen will ______. the dollar will ______ and the yen will ______. 50 POINTS Which quote from the text illustrates that Eileen Collins' enthusiasm for space travel remains high?"Collins joined the Air Force, and during her first month of training, her base was visited by the newest astronaut class--thefirst to include women--and her path was set."O "In fact, Collins discourages people from looking at what other astronauts are in and choosing that."O "When the Shuttle's ready to fly, we'll be ready to fly."O "On her last mission, Eileen Collins became the first (and currently only) female Shuttle commander." A circuit consists of a 100 ohm resistor and a 150 nf capacitor wired in series and connected to a 6 v battery. what is the maximum charge the capacitor can store? you have six slices of bread, three tomato slices, and two cheese slices. how many tomato-cheese sandwiches can you make? which ingredient(s) limit the number of sandwiches you can make? give all possible polar coordinates for the point (7,73) given in rectangular coordinates. which four types are social publishing sites? microsharing sites, media sharing sites, social bookmarking and news sites. which of the A nurse begins his shift by reading the following shift report. The nurse interprets these results as indicating which of the following?Miscellaneous reports:H.B. age 78; Hyperventilating, RR 36 bpm;C/o dizziness, sob, tingling in hands and feet, weakness; Anxious.ABG: pH 7.48; PaCO2: 33mmHg1) metabolic acidosis2) acute respiratory failure3) respiratory alkalosis4) anxiety reaction 1. List The names of employees and his/her division who do not work on another division's project (hint: correlated subquery)2. List the names of projects that Chen and Larry both works on but Larry spent more time on it.3. List the name of divisions that has at least 2 employees spend more than 30 hours on web development. Is profit motive a planned economic or market economic or mixed economic