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1. ### Confidence interval vs. expanded uncertainty

You have hit my question exactly! :) What do they mean by confidence? I can't tell at all. I can't figure out what this value represents. Regarding your first question about the covariance, I think they are assuming the covariance is zero on a previous page. For example, see the section for...
2. ### Confidence interval vs. expanded uncertainty

Hi all, thanks for responding. Sure thing, here are some sites that refer to the "expanded uncertainty". Here is a link to the National Institute of Standards and Technology: https://www.itl.nist.gov/div898/handbook/mpc/section5/mpc57.htm Here is a link to an ISO page...
3. ### Confidence interval vs. expanded uncertainty

Hi, I'm struggling with the difference between confidence interval and expanded uncertainty. I understand a confidence interval around the mean. For example, a 95% confidence interval around the mean says that if N samples were taken 100 times and a confidence interval was recalculated each...
4. ### Tolerance Interval for Standard Uncertainty

Any way you could retype the link to the "Tolerance_Limits_..." document? The link seems to be broken when I click on it. Also, maybe I've stumbled across an answer? As you know, my original concern was that when reading about tolerance intervals, they use a special "k-factor" instead of the...
5. ### Tolerance Interval for Standard Uncertainty

Hi, So I've been reading the document to try and get a better grasp for answering your question. Turns out X is 1. Let me explain. The purpose of the calculation is to put an upper limit (via a 95/95 tolerance interval) on the relative change of a parameter. So, if the value "1.645*S" (from my...
6. ### Tolerance Interval for Standard Uncertainty

So I'm not 100% clear on that yet, but I think it's the mean of F determined when calculating all of the standard deviations (sx, sy, etc.).
7. ### Tolerance Interval for Standard Uncertainty

Hi fed2, thanks for the response. So, if I understand your suggestion, you're saying to use the student-t values to look up zx, zy, etc, right? I believe this is what they are already doing to come up with the zx, zy, ... values that are applied inside the square root. But I'm wondering if this...
8. ### Tolerance Interval for Standard Uncertainty

Hello all, Here's my question. I'm reading an old work document written back in the 80s. The purpose is to calculate a 95/95 one-sided tolerance interval for a parameter of interest. To do this, they use the following equation: x + 1.645*S where S = sqrt( (dF/dx * zx * sx)^2 + (dF/dy * zy *...