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I understand what confidence intervals are and how we interpret them, but I guess one thing that I never realized in understanding this concept was what exactly the single confidence interval estimate we provide actually means. So as an example, say we find a 95% confidence interval for a parameter estimate $\beta$. Say we got a point estimate $\hat{\beta}$ as well as the necessary standard error, $\text{s}(\hat{\beta})$ and critical value (we'll use a t-statistic here), $t(1-\alpha; n-p)$. So we go on to construct a confidence interval:

$$ \hat{\beta} \pm t(1-\frac{\alpha}{2}; n-p)\cdot\text{s}(\hat{\beta})$$

So the interpretation of this is that over repeated sampling, 95% of the constructed interval estimates will contain the true value of the parameter. But as you see above in practice I calculated a confidence interval explicitly. So how do we frame this with regards to the whole notion of confidence intervals? Would I say this one explicitly calculated confidence interval is one of the possible intervals that would arise 95% of the time? What is it I'm missing in the understanding of this?

I'm aware of the popular post: What, precisely, is a confidence interval? and actually I have it saved as a bookmark. The overall idea of the CI is not what I'm stuck on it is these sort of individual outputs.

dc3rd
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    You may find [this](https://discourse.datamethods.org/t/language-for-communicating-frequentist-results-about-treatment-effects/934#accurate-interpretation-of-compatibility-interval-11) helpful – Demetri Pananos Nov 05 '21 at 03:11
  • So if I interpreted the linked passage correctly, the explicit interval serves as a "plausible" range for what the true value could be. But only as a heuristic not to be taken as precise? – dc3rd Nov 05 '21 at 04:26
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    Correct. “Plausible” depends explicitly on alpha, so it’s really just a heuristic. – Demetri Pananos Nov 05 '21 at 04:37
  • Alright then. Thank you my fellow 6ix-er. Catch you on King Street or at a Data Meetup. – dc3rd Nov 05 '21 at 04:39

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