Determine the Counts Required to be Statistically Significant
  1. This is similar to the last part that was discussed in determining error using %SD
  2. However, in this application the question that must be answered is, "How many counts are needed to attain a certain level of confidence given a specific SD?"
  3. The formulas are stated below

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    1. Note that there are there are 3 levels of confidence where SD = 68%, 95%, or 99%
    2. In this case one must select the level of confidence and then you can determine the amount of counts required to attain that level of confidence

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    3. The example used here notes the requirement that one wants to use a 99% level of confidence and attain no more than a 2% error. How many counts do you need to collect in order to achieve this?
  4. Homework
    1. Determine a 1% error at 68%, 95%, and 99% level of confidence
    2. Do the amount of count increase as your level of confidence increase?

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