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Margin of Error

Discussion in 'Off Topic' started by Mark Laszczuk, 11th Jun, 2008.

  1. Mark Laszczuk

    Mark Laszczuk Well-Known Member

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    Brisbane
    I'm trying to work out a formula for calculating margin of error in Excel. Had a look around Google, but didn't find what I was looking for. What I need to do is determine the percentage difference between two numbers.

    Let's say I project a dividend of 50 cents for a given year. However, the actual dividend is 45 cents. So the margin of error on this is about 10%, give or take (45 cents is 90% of 50 cents).

    Does anyone have a formula I could pinch please?

    Thanks in advance.

    Mark
     
  2. Simon Hampel

    Simon Hampel Co-founder Staff Member

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    "Margin of Error" has a specific statistical meaning and relates to sample sizes and error rates from survey data. I'm not sure if that's actually what you are looking for ?

    If you just want to calculate the percentage difference between two numbers (predicted and actual), then surely this would do the trick:

    A1 = prediction
    A2 = actual

    formula =(A2-A1)/A1

    if the actual is less than the prediction, result will be negative. Result can be formatted as a percentage.

    Is that what you want? Or are you after something more statistical?
     
  3. Mark Laszczuk

    Mark Laszczuk Well-Known Member

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    Location:
    Brisbane
    Mate, that's exactly what I needed, thanks! I was racking my brains for about an hour last night trying to work out the formula for it. Maybe I shouldn't try so hard at 3 in the morning.

    Mark