Expected number of offers until house is sold
Clash Royale CLAN TAG#URR8PPP
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4
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I am selling my house, and have decided to accept the first offering
exceeding $K$ dollars. Assuming that offers are independent rv with
common distribution $F$, find the expected number of offers received
before I sell the house.
Try
I call $X$ to be number of offers receiver before house is sold. Suppose we have $n$ such offers and call them $X_1,X_2,...,X_n$. Therefore, $X = sum X_i$. We have that
$$ E(X) = E(X_1) + .. + E(X_n) $$
Since all $X_i$ have common distribution $F$, then
$$ E(X_i) = intlimits_0^K x f(x) $$
where $f = F' $. So,
$$ E(X) = n intlimits_0^K x f(x) $$
is this correct?
probability
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up vote
4
down vote
favorite
I am selling my house, and have decided to accept the first offering
exceeding $K$ dollars. Assuming that offers are independent rv with
common distribution $F$, find the expected number of offers received
before I sell the house.
Try
I call $X$ to be number of offers receiver before house is sold. Suppose we have $n$ such offers and call them $X_1,X_2,...,X_n$. Therefore, $X = sum X_i$. We have that
$$ E(X) = E(X_1) + .. + E(X_n) $$
Since all $X_i$ have common distribution $F$, then
$$ E(X_i) = intlimits_0^K x f(x) $$
where $f = F' $. So,
$$ E(X) = n intlimits_0^K x f(x) $$
is this correct?
probability
add a comment |Â
up vote
4
down vote
favorite
up vote
4
down vote
favorite
I am selling my house, and have decided to accept the first offering
exceeding $K$ dollars. Assuming that offers are independent rv with
common distribution $F$, find the expected number of offers received
before I sell the house.
Try
I call $X$ to be number of offers receiver before house is sold. Suppose we have $n$ such offers and call them $X_1,X_2,...,X_n$. Therefore, $X = sum X_i$. We have that
$$ E(X) = E(X_1) + .. + E(X_n) $$
Since all $X_i$ have common distribution $F$, then
$$ E(X_i) = intlimits_0^K x f(x) $$
where $f = F' $. So,
$$ E(X) = n intlimits_0^K x f(x) $$
is this correct?
probability
I am selling my house, and have decided to accept the first offering
exceeding $K$ dollars. Assuming that offers are independent rv with
common distribution $F$, find the expected number of offers received
before I sell the house.
Try
I call $X$ to be number of offers receiver before house is sold. Suppose we have $n$ such offers and call them $X_1,X_2,...,X_n$. Therefore, $X = sum X_i$. We have that
$$ E(X) = E(X_1) + .. + E(X_n) $$
Since all $X_i$ have common distribution $F$, then
$$ E(X_i) = intlimits_0^K x f(x) $$
where $f = F' $. So,
$$ E(X) = n intlimits_0^K x f(x) $$
is this correct?
probability
probability
asked 2 hours ago
Jimmy Sabater
1,800216
1,800216
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1 Answer
1
active
oldest
votes
up vote
3
down vote
accepted
This is completely the wrong way to do it. $F(K)$ gives the probability that one offer is less than $K$, i.e. the offer fails, so $1-F(K)$ is the probability of an offer succeeding. Now the number of offers received follows a geometric distribution with success rate $1-F(K)$, so the expected number of offers is its reciprocal, $frac11-F(K)$.
add a comment |Â
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
3
down vote
accepted
This is completely the wrong way to do it. $F(K)$ gives the probability that one offer is less than $K$, i.e. the offer fails, so $1-F(K)$ is the probability of an offer succeeding. Now the number of offers received follows a geometric distribution with success rate $1-F(K)$, so the expected number of offers is its reciprocal, $frac11-F(K)$.
add a comment |Â
up vote
3
down vote
accepted
This is completely the wrong way to do it. $F(K)$ gives the probability that one offer is less than $K$, i.e. the offer fails, so $1-F(K)$ is the probability of an offer succeeding. Now the number of offers received follows a geometric distribution with success rate $1-F(K)$, so the expected number of offers is its reciprocal, $frac11-F(K)$.
add a comment |Â
up vote
3
down vote
accepted
up vote
3
down vote
accepted
This is completely the wrong way to do it. $F(K)$ gives the probability that one offer is less than $K$, i.e. the offer fails, so $1-F(K)$ is the probability of an offer succeeding. Now the number of offers received follows a geometric distribution with success rate $1-F(K)$, so the expected number of offers is its reciprocal, $frac11-F(K)$.
This is completely the wrong way to do it. $F(K)$ gives the probability that one offer is less than $K$, i.e. the offer fails, so $1-F(K)$ is the probability of an offer succeeding. Now the number of offers received follows a geometric distribution with success rate $1-F(K)$, so the expected number of offers is its reciprocal, $frac11-F(K)$.
answered 2 hours ago


Parcly Taxel
38k137097
38k137097
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