Waiting time in Poisson processAverage waiting time in a Poisson processprobability (waiting time = infinity) for a poisson processHow to calculate the average waiting time from an in-homogeneous Poisson process.Waiting time for two independent poisson processesAre these facts about the Poisson process correct?Number of arrivals of a compound Poisson process?Poisson process with dead timePoisson process: waiting time probabilitiesConditional waiting time in Poisson processNumber of Events Registered in a Poisson Process
Should I join office cleaning event for free?
How is the claim "I am in New York only if I am in America" the same as "If I am in New York, then I am in America?
How can the DM most effectively choose 1 out of an odd number of players to be targeted by an attack or effect?
Why CLRS example on residual networks does not follows its formula?
If Manufacturer spice model and Datasheet give different values which should I use?
Why is this code 6.5x slower with optimizations enabled?
Validation accuracy vs Testing accuracy
Is Social Media Science Fiction?
How is it possible for user's password to be changed after storage was encrypted? (on OS X, Android)
Extreme, but not acceptable situation and I can't start the work tomorrow morning
Circuitry of TV splitters
How do you conduct xenoanthropology after first contact?
Are tax years 2016 & 2017 back taxes deductible for tax year 2018?
N.B. ligature in Latex
What Brexit solution does the DUP want?
Prevent a directory in /tmp from being deleted
What defenses are there against being summoned by the Gate spell?
Accidentally leaked the solution to an assignment, what to do now? (I'm the prof)
What is the logic behind how bash tests for true/false?
Can a German sentence have two subjects?
What do you call something that goes against the spirit of the law, but is legal when interpreting the law to the letter?
Why is an old chain unsafe?
Chess with symmetric move-square
whey we use polarized capacitor?
Waiting time in Poisson process
Average waiting time in a Poisson processprobability (waiting time = infinity) for a poisson processHow to calculate the average waiting time from an in-homogeneous Poisson process.Waiting time for two independent poisson processesAre these facts about the Poisson process correct?Number of arrivals of a compound Poisson process?Poisson process with dead timePoisson process: waiting time probabilitiesConditional waiting time in Poisson processNumber of Events Registered in a Poisson Process
$begingroup$
Let $X(t) : t geq 0$ be a Poisson process with rate $lambda$, and let $W_n$ denote the waiting time for the $n$-th event. For $s geq 0$, determine $P( W_X(t) leq t+s)$ and $P( W_X(t)+2 leq t+s)$.
Here's what I've tried.
For $W_X(t)$ to be less than $t+s$, the $X(t)$-th event must occur before time $t+s$. This implies that at least $X(t)$ many events must occur before time $t+s$, so we have
$$
P( W_X(t) leq t+s)
= P( X(t+s) geq X(t))
= P( X(t+s) - X(t) geq 0)
= 1.
$$
Applying similar logic to the second one,
beginalign*
P(W_X(t)+2 leq t + s)
&= P(X(t+s) geq X(t) + 2) \
&= 1 - P(X(t+s) - X(t) < 2) \
&= 1 - P(X(t+s) - X(t) = 0) - P(X(t+s) - X(t) = 1) \
&= 1 - e^-lambda t - lambda t e^-lambda t.
endalign*
Is what I've done ok? I'm getting the niggling feeling that I should be using the uniform distribution somehow. Please advise, thanks!
proof-verification stochastic-processes poisson-process
$endgroup$
add a comment |
$begingroup$
Let $X(t) : t geq 0$ be a Poisson process with rate $lambda$, and let $W_n$ denote the waiting time for the $n$-th event. For $s geq 0$, determine $P( W_X(t) leq t+s)$ and $P( W_X(t)+2 leq t+s)$.
Here's what I've tried.
For $W_X(t)$ to be less than $t+s$, the $X(t)$-th event must occur before time $t+s$. This implies that at least $X(t)$ many events must occur before time $t+s$, so we have
$$
P( W_X(t) leq t+s)
= P( X(t+s) geq X(t))
= P( X(t+s) - X(t) geq 0)
= 1.
$$
Applying similar logic to the second one,
beginalign*
P(W_X(t)+2 leq t + s)
&= P(X(t+s) geq X(t) + 2) \
&= 1 - P(X(t+s) - X(t) < 2) \
&= 1 - P(X(t+s) - X(t) = 0) - P(X(t+s) - X(t) = 1) \
&= 1 - e^-lambda t - lambda t e^-lambda t.
endalign*
Is what I've done ok? I'm getting the niggling feeling that I should be using the uniform distribution somehow. Please advise, thanks!
proof-verification stochastic-processes poisson-process
$endgroup$
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05
add a comment |
$begingroup$
Let $X(t) : t geq 0$ be a Poisson process with rate $lambda$, and let $W_n$ denote the waiting time for the $n$-th event. For $s geq 0$, determine $P( W_X(t) leq t+s)$ and $P( W_X(t)+2 leq t+s)$.
Here's what I've tried.
For $W_X(t)$ to be less than $t+s$, the $X(t)$-th event must occur before time $t+s$. This implies that at least $X(t)$ many events must occur before time $t+s$, so we have
$$
P( W_X(t) leq t+s)
= P( X(t+s) geq X(t))
= P( X(t+s) - X(t) geq 0)
= 1.
$$
Applying similar logic to the second one,
beginalign*
P(W_X(t)+2 leq t + s)
&= P(X(t+s) geq X(t) + 2) \
&= 1 - P(X(t+s) - X(t) < 2) \
&= 1 - P(X(t+s) - X(t) = 0) - P(X(t+s) - X(t) = 1) \
&= 1 - e^-lambda t - lambda t e^-lambda t.
endalign*
Is what I've done ok? I'm getting the niggling feeling that I should be using the uniform distribution somehow. Please advise, thanks!
proof-verification stochastic-processes poisson-process
$endgroup$
Let $X(t) : t geq 0$ be a Poisson process with rate $lambda$, and let $W_n$ denote the waiting time for the $n$-th event. For $s geq 0$, determine $P( W_X(t) leq t+s)$ and $P( W_X(t)+2 leq t+s)$.
Here's what I've tried.
For $W_X(t)$ to be less than $t+s$, the $X(t)$-th event must occur before time $t+s$. This implies that at least $X(t)$ many events must occur before time $t+s$, so we have
$$
P( W_X(t) leq t+s)
= P( X(t+s) geq X(t))
= P( X(t+s) - X(t) geq 0)
= 1.
$$
Applying similar logic to the second one,
beginalign*
P(W_X(t)+2 leq t + s)
&= P(X(t+s) geq X(t) + 2) \
&= 1 - P(X(t+s) - X(t) < 2) \
&= 1 - P(X(t+s) - X(t) = 0) - P(X(t+s) - X(t) = 1) \
&= 1 - e^-lambda t - lambda t e^-lambda t.
endalign*
Is what I've done ok? I'm getting the niggling feeling that I should be using the uniform distribution somehow. Please advise, thanks!
proof-verification stochastic-processes poisson-process
proof-verification stochastic-processes poisson-process
asked Mar 22 at 8:44
jessicajessica
7719
7719
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05
add a comment |
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
After much discussion with another student, we've determined that what I did is correct except for a typo in the last line. The answer is
$$
P(W_X(t)+2 leq t + s)
= 1 - e^-lambda s - lambda s e^-lambda s.
$$
Rather than focusing on the Poisson process on its own, it's better to think of things as a renewal process and consider the special case of Poisson processes.
$endgroup$
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
return StackExchange.using("mathjaxEditing", function ()
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
);
);
, "mathjax-editing");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "69"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3157902%2fwaiting-time-in-poisson-process%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
After much discussion with another student, we've determined that what I did is correct except for a typo in the last line. The answer is
$$
P(W_X(t)+2 leq t + s)
= 1 - e^-lambda s - lambda s e^-lambda s.
$$
Rather than focusing on the Poisson process on its own, it's better to think of things as a renewal process and consider the special case of Poisson processes.
$endgroup$
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
add a comment |
$begingroup$
After much discussion with another student, we've determined that what I did is correct except for a typo in the last line. The answer is
$$
P(W_X(t)+2 leq t + s)
= 1 - e^-lambda s - lambda s e^-lambda s.
$$
Rather than focusing on the Poisson process on its own, it's better to think of things as a renewal process and consider the special case of Poisson processes.
$endgroup$
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
add a comment |
$begingroup$
After much discussion with another student, we've determined that what I did is correct except for a typo in the last line. The answer is
$$
P(W_X(t)+2 leq t + s)
= 1 - e^-lambda s - lambda s e^-lambda s.
$$
Rather than focusing on the Poisson process on its own, it's better to think of things as a renewal process and consider the special case of Poisson processes.
$endgroup$
After much discussion with another student, we've determined that what I did is correct except for a typo in the last line. The answer is
$$
P(W_X(t)+2 leq t + s)
= 1 - e^-lambda s - lambda s e^-lambda s.
$$
Rather than focusing on the Poisson process on its own, it's better to think of things as a renewal process and consider the special case of Poisson processes.
answered Mar 27 at 10:01
jessicajessica
7719
7719
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
add a comment |
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
1
1
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
$begingroup$
As you pointed out earlier, $P(W_X(t) + 2 leq t+s) = P(X(t+s) geq X(t) + 2) = P(X(t+s) -X(t) geq 2)$. Since the process is Poisson, you can write $P(W_X(t) + 2 leq t+s) = P(X(s) - X(0) geq 2$. Note that the last statement is not true for a renewal process, except for the special case of the Poisson process. For a renewal process $X(t)$ counts the number of renewal events till time $t$ (including events if any at time t), so at time $t$, $W_X(t)$ tells you the last renewal epoch before time $t$ (again we account for renewals at $t$ if any).
$endgroup$
– Sudheer
Mar 27 at 12:55
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3157902%2fwaiting-time-in-poisson-process%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Frankly, my understanding of poisson processes is really weak. Have I understood $W_X(t)$ correctly? I've only ever encountered things like $W_2$ and $W_n$ so I'm really at a loss
$endgroup$
– jessica
Mar 22 at 9:05