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Homework Help: Help calculating uncertainty of slope & intercept of cal. curves. uncertainty ?s

  1. Jul 18, 2011 #1
    1. The problem statement, all variables and given/known data

    I need assistance in learning the proper way to calculate error/uncertainty in a few things for my undergrad thesis.

    2. Relevant equations

    1) how to calculate the uncertainty in the slope and intercept of calibration curves (peak area vs mol of compound) I have made via excel.
    2) help calculating the uncertainty in a standard tank.

    3. The attempt at a solution

    I can post my excel files, but my basic attempt at this has been calculating thinds like stdev and others, but I have done this before in a course. What I may bee missing is some plugin for excel. My professor mentioned that I should use the data analysis add-in for excel. I installed this, but am unsure of how to use it.

    Sorry if this is not what is typically asked here. The template makes it seem like homework questions should be posted here.
    Last edited: Jul 18, 2011
  2. jcsd
  3. Jul 18, 2011 #2
    In excel, select Tools/Data Analysis..., then choose Regression in the dialog. Now select your x and y data for the "Input X range" and "Input Y range", check anything else you want (experiment with this), and click OK. The numbers you want are under "Coefficient" and "Standard Error" in one of the tables that appears.
  4. Jul 18, 2011 #3
    I do remember this now. Thanks, I found this earlier by playing around with the data analysis. But was looking for uncertainty when all I wanted was standard error really.
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