All Questions
4
questions
0
votes
0
answers
25
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Variance in a confidence interval for a percentage in a survey sample
I'm teaching an undergrad class on survey sampling (not in the stats department) for the first time. This seems like a very basic question that I should know the answer to, but I can't find it ...
- 61
1
vote
1
answer
962
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Confidence interval for $\sigma^2$
I started with any distribution and underwent the CLT on $\sqrt{n}(\widehat{\sigma}^2 - \sigma^2)$ where
$$
\widehat{\sigma}^2 = \frac{1}{n}\sum_{i=1}^n (X_i - \mu)^2
$$
is a sample mean of $\sigma^2$...
5
votes
1
answer
9k
views
Confidence interval for the standard deviation on a bimodal distribution
I have a bimodal distribution, and I wish to estimate the mean and standard deviation of the population (well, these could be 2 sub-populations according to the shape).
With the mean I have no ...
- 51
6
votes
2
answers
3k
views
Putting a confidence interval on the mean of a very rare event
I'm simulating an extremely rare event (the detection of weighted photon packets in a highly absorbing material). For example, I may simulate the transmission of 1e9 photons and only detect 10 of them ...
- 373