+ Reply to Thread
Results 1 to 9 of 9

Thread: Probability in an "on-off" cycle

  1. #1
    Points: 15, Level: 1
    Level completed: 29%, Points required for next Level: 35

    Posts
    5
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Probability in an "on-off" cycle




    A process runs in a cycle and has a wait time prior to and then after a period of activity. So say at time = 0 the process is "off" for a count of 10, then "on" for a count of 4, then "off" for a count of 10. That would be one cycle. The cycle may or may not restart right away. If I have some number - say 20 for instance - of these processes starting randomly, how do I compute the probability that a chosen number of them - 5 for instance - are in the "on" state?

  2. #2
    TS Contributor
    Points: 22,410, Level: 93
    Level completed: 6%, Points required for next Level: 940

    Posts
    3,020
    Thanks
    12
    Thanked 565 Times in 537 Posts

    Re: Probability in an "on-off" cycle

    What are the distributions of those waiting times staying on/off state respectively? Please provide more information / assumptions for these.

    E.g. this maybe modeled by a continuous Markov chain if exponential distribution is chosen.

  3. #3
    Points: 15, Level: 1
    Level completed: 29%, Points required for next Level: 35

    Posts
    5
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: Probability in an "on-off" cycle

    Quote Originally Posted by BGM View Post
    What are the distributions of those waiting times staying on/off state respectively? Please provide more information / assumptions for these.

    E.g. this maybe modeled by a continuous Markov chain if exponential distribution is chosen.
    There is no additional information. Beyond that I don't understand your question.

  4. #4
    Devorador de queso
    Points: 95,540, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Awards:
    Posting AwardCommunity AwardDiscussion EnderFrequent Poster
    Dason's Avatar
    Location
    Tampa, FL
    Posts
    12,930
    Thanks
    307
    Thanked 2,629 Times in 2,245 Posts

    Re: Probability in an "on-off" cycle

    Is this for homework?
    I don't have emotions and sometimes that makes me very sad.

  5. #5
    Points: 15, Level: 1
    Level completed: 29%, Points required for next Level: 35

    Posts
    5
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: Probability in an "on-off" cycle

    Quote Originally Posted by Dason View Post
    Is this for homework?
    Is this strictly a homework forum?

  6. #6
    Devorador de queso
    Points: 95,540, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Awards:
    Posting AwardCommunity AwardDiscussion EnderFrequent Poster
    Dason's Avatar
    Location
    Tampa, FL
    Posts
    12,930
    Thanks
    307
    Thanked 2,629 Times in 2,245 Posts

    Re: Probability in an "on-off" cycle

    No - of course not. But we do treat homework a little differently and if it was homework then I would tell you to ask your instructor for some additional info because the problem isn't completely well defined at the moment.

    If it's not homework then maybe you can provide some more information about the problem itself.
    I don't have emotions and sometimes that makes me very sad.

  7. #7
    Points: 15, Level: 1
    Level completed: 29%, Points required for next Level: 35

    Posts
    5
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: Probability in an "on-off" cycle

    Quote Originally Posted by Dason View Post
    the problem isn't completely well defined at the moment.
    Why is that?

  8. #8
    Devorador de queso
    Points: 95,540, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Awards:
    Posting AwardCommunity AwardDiscussion EnderFrequent Poster
    Dason's Avatar
    Location
    Tampa, FL
    Posts
    12,930
    Thanks
    307
    Thanked 2,629 Times in 2,245 Posts

    Re: Probability in an "on-off" cycle

    Is the "process" always exactly as you described? (off for 10, on for 4, off for 10) and then there isn't enough information describing what is actually going on and with what probabilities these actions happen in this:
    The cycle may or may not restart right away. If I have some number - say 20 for instance - of these processes starting randomly
    So what happens after the "process" ends - is it still considered off? If so then I don't really get what is happening or what the difference is between the process being 'in cycle' but off and the process not being in cycle and off.

    If there are differences then without knowing something about the probability distribution of how long it takes the cycle to start up again we really can't say anything.
    I don't have emotions and sometimes that makes me very sad.

  9. #9
    Points: 15, Level: 1
    Level completed: 29%, Points required for next Level: 35

    Posts
    5
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Re: Probability in an "on-off" cycle


    Quote Originally Posted by Dason View Post

    If there are differences then without knowing something about the probability distribution of how long it takes the cycle to start up again we really can't say anything.
    OK. So the idea would be "off" vs "in-cycle but waiting". So a computer program for example may be "off" in which case it can start at any random time (maybe it waits for a keypress or some other random event), but once it starts it has to wait X counts before actually consuming CPU for some fixed time - then waits X and goes "off". So we might say we want to know the probability that for some number of these programs that CPU is being consumed. The random event - keypress or whatever - I guess would be Gaussian.

    How would the approach to this differ if there were no difference between "on" and "waiting"?

+ Reply to Thread

           




Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts






Advertise on Talk Stats