Notices
Results 1 to 5 of 5

Thread: Statistics notation

  1. #1 Statistics notation 
    New Member
    Join Date
    Apr 2011
    Posts
    1
    In my lecture notes on confidence intervals the lecturer wrote this:
    Recall that measurements tend to follow a normal distribution. To describe the normal distribution and answer useful questions (as in the previous chapter), we need to know two numbers; the expectation or mean μ and the standard deviation (square root of the variance) σ. Then the quantity we measure X follows the normal distribution:
    X ~ N(μ, σ2)
    I don't understand the notation of that bolded text. I know X is a random variable, μ is the population mean and σ is the population standard deviation but what does the ~ mean? Also the N(μ, σ2) I assume means normal distribution but is that some kind of standard notation for distributions? For example if I said N(23,9) would that mean the normal distribution with a mean of 23 and standard deviation of 9?[/b]


    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Professor
    Join Date
    Jul 2008
    Location
    New York State
    Posts
    1,265
    To repeat what I said in another forum. Mean = 23, variance = 9, standard deviation = 3.


    Reply With Quote  
     

  4. #3  
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by mathman
    To repeat what I said in another forum. Mean = 23, variance = 9, standard deviation = 3.
    I know of one other forum where this guy has posted the same question, the answer to which is painfully obvious (Your response is, of course, correct.) You did not respond in that one. So we have a loweer bound of 3 for the number of forums with the same post/question.

    Annoying isn't it ?
    Reply With Quote  
     

  5. #4  
    Forum Professor
    Join Date
    Jul 2008
    Location
    New York State
    Posts
    1,265
    Quote Originally Posted by DrRocket
    Quote Originally Posted by mathman
    To repeat what I said in another forum. Mean = 23, variance = 9, standard deviation = 3.
    I know of one other forum where this guy has posted the same question, the answer to which is painfully obvious (Your response is, of course, correct.) You did not respond in that one. So we have a loweer bound of 3 for the number of forums with the same post/question.

    Annoying isn't it ?
    What is the other forum that you saw this question?
    Reply With Quote  
     

  6. #5  
    . DrRocket's Avatar
    Join Date
    Aug 2008
    Posts
    5,486
    Quote Originally Posted by mathman
    Quote Originally Posted by DrRocket
    Quote Originally Posted by mathman
    To repeat what I said in another forum. Mean = 23, variance = 9, standard deviation = 3.
    I know of one other forum where this guy has posted the same question, the answer to which is painfully obvious (Your response is, of course, correct.) You did not respond in that one. So we have a loweer bound of 3 for the number of forums with the same post/question.

    Annoying isn't it ?
    What is the other forum that you saw this question?
    http://www.scienceforums.net/topic/5...tics-notation/
    Reply With Quote  
     

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