+ Reply to Thread
Results 1 to 4 of 4

Thread: Not understanding Normal Distribution

  1. #1
    Points: 5,087, Level: 45
    Level completed: 69%, Points required for next Level: 63

    Location
    Maryland
    Posts
    2
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Not understanding Normal Distribution




    I am having trouble wrapping my head around normal distributions and the revelance it has with statistics.--- Can someone help me to understand in laymen terms versus book terms... Thanks

  2. #2
    TS Contributor
    Points: 17,636, Level: 84
    Level completed: 58%, Points required for next Level: 214
    JohnM's Avatar
    Posts
    1,948
    Thanks
    0
    Thanked 6 Times in 5 Posts
    The normal distribution, or "bell curve," represents how scores or whatever we are measuring are distributed. In general terms, if we were to measure some attribute in the population, say a person's height, we might find that most of them are clustered near the average, while maybe a few are further away, either lower or higher. So, the higher the curve, the more scores there are in that range or region.

    Knowledge of how scores are distributed then allows us to determine how likely or unlikely it is to obtain a particular score. The height of the curve, then, also tells us the relative probability of getting a particular score, or the probability or percentage of the population that falls within a certain range.

    For example, if you measured the heights of adult males, you might find that most of them cluster around 68-73" but there may be a few below or above that range.

    These concepts form the basis for statistical inference - when we draw a sample from the populaton, can we reach any conclusions about the shape of the distribution of the population? Also, if someone were to claim that the average adult male height is 75" or some other unlikely value, we could use sampling and the normal distribution to attempt to refute that claim.

    Hope this helps a bit.....
    Last edited by JohnM; 10-24-2005 at 12:48 PM.

  3. #3
    Points: 5,087, Level: 45
    Level completed: 69%, Points required for next Level: 63

    Location
    Maryland
    Posts
    2
    Thanks
    0
    Thanked 0 Times in 0 Posts
    Thank you that was very helpful- another question is when you mentioned, "knowledge of how scores are distributed then allows us to determine how likely or unliekely it is to obtain a particular score." What does the particular score represent--- I think my problem is I am not able to visualize what it actually means... sounds funny huh!!!

  4. #4
    TS Contributor
    Points: 17,636, Level: 84
    Level completed: 58%, Points required for next Level: 214
    JohnM's Avatar
    Posts
    1,948
    Thanks
    0
    Thanked 6 Times in 5 Posts

    The scores can represent anything that you can observe and/or measure. i.e., height, weight, "customer satisfaction," amount of rainfall, temperature, percentage of people in the population who catch a cold during the winter...

+ Reply to Thread

           




Similar Threads

  1. Replies: 2
    Last Post: 05-11-2011, 01:35 PM
  2. help understanding t-distribution
    By lilyungn in forum Statistics
    Replies: 5
    Last Post: 06-21-2010, 11:56 PM
  3. Is a subset of a normal distribution normal?
    By bordonbert in forum Probability
    Replies: 4
    Last Post: 10-29-2009, 03:54 AM
  4. Normal? Bimodal normal? Some other distribution?
    By statsCZ in forum Statistical Research
    Replies: 4
    Last Post: 01-28-2009, 08:31 AM
  5. Replies: 0
    Last Post: 01-23-2008, 11:32 PM

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