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5 votes
3 answers
682 views

confidence intervals for proportions containing a theoretically impossible value (zero)

This is really a hypothetical question not related to an actual issue I have, so this question is just out of curiosity. I'm aware of this other related question What should I do when a confidence ...
Coris's user avatar
  • 53
4 votes
1 answer
124 views

Confidence interval on ratio of estimates for exponential random variables

Given exponential random variable X, the MLE for the scale parameter is $\hat{\beta_x} = \bar{x}$, and the confidence interval for that estimate is: $$\frac{2n\bar{x}}{\chi^2_{\frac{\alpha}{2},2n}} &...
feetwet's user avatar
  • 1,162
1 vote
1 answer
41 views

Combining two success runs in parallel

The goal is to calculate the reliability of a process. Here reliability is defined as follows: Definitions and tests I used Let $X$ be a random variable that is equal to $1$ when no defect is present ...
lulufofo's user avatar
  • 472
0 votes
1 answer
539 views

Maximum-likelihood estimator for data points with errors

Suppose there are N measurements of a random variable x which has Gaussian p.d.f. with unknown mean $\mu$ and variance $\sigma^2$. Classical textbook solution for estimation $\mu$ and $\sigma$ is to ...
Alexander's user avatar
3 votes
0 answers
39 views

Adjusting confidence interval of estimator by efficiency

Summary: If we have an unbiased MLE $\widehat{\sigma_1}$ of an exponential distribution parameter, and the confidence intervals for its estimates are given by the $\chi^2$ distribution; and we find ...
feetwet's user avatar
  • 1,162
0 votes
0 answers
38 views

Confusing usage of Central Limit Theorem

The CLT defined in Introduction to Mathematical Statistics (Hogg) 8th ed., states that given the samples $\mathbf X\sim\mathcal N(\mu,\sigma) $ with the mean and variance estimator $\bar X,S^2$, the ...
wd violet's user avatar
  • 777
1 vote
0 answers
163 views

Confidence Intervals for Normalized Random Variables

I think I have a pretty simple question about constructing confidence intervals for normalized random variables. If I have i.i.d random variables $X_1, X_2, X_3, ..., X_n \sim F$ for some distribution ...
mathplebeian's user avatar
1 vote
0 answers
47 views

Correct approach for combining confidence intervals from multiple estimators

Let's say I have an estimation from 2 different people about human population of a small town. Both are (calibrated) 90% CIs: Expert 1: 3,000-4,000 Expert 2: 3,000-50,000 (Intentionally much wider ...
George Ty's user avatar
0 votes
1 answer
312 views

Do confidence intervals make sense for win rates in sport?

Imagine we have 2 teams play 10 matches against each other with team A winning 6 of them I.e. 60%. In this setting do confidence intervals for the probability of winning make sense? On one hand I ...
gowerc's user avatar
  • 810
1 vote
0 answers
128 views

Confidence interval for exponentially distributed estimator

We have an estimator $\hat{\theta}\geq 0$ for $\theta$, with distribution function $P\{\hat{\theta}\leq t \}=1-e^{-t/\theta}$, which we can recognize as the cdf of the exponential distribution. Our ...
Joe's user avatar
  • 85
0 votes
0 answers
88 views

Replace parameter with estimate for confidence interval. Case Beta distribution

I'm trying to get a confidence interval for the mean of a beta distribution $B(\theta,1)$, using $[\hat\theta - z_{1-\alpha/2}\hat\sigma_{\hat\theta};\hat\theta + z_{1-\alpha/2}\hat\sigma_{\hat\theta}]...
Seb's user avatar
  • 59
13 votes
3 answers
2k views

Revisiting the Rule of Three

The rule of three is a method for calculating a 95% confidence interval when estimating $p$ from a set of $n$ IID Bernoulli trials with no successes. My understanding from its derivation is that the ...
Set's user avatar
  • 1,463
0 votes
1 answer
4k views

What's the advantage of a point estimate over an interval estimate?

A point estimate is : A single numerical value that is used to estimate the corresponding population parameter. Whereas an interval estimate is : An estimate that consists of two numerical values ...
Positron12's user avatar
0 votes
0 answers
24 views

How to estimate differences between two normal means when variances are tested to be unequal

Let $X_1 X_2...X_n, Y_1 Y_2...Y_n$ be $\sim N(\mu_x$, $\sigma_x^2$), $\sim N(\mu_y, \sigma_y^2$). I want to estimate ($\mu_x - \mu_y$) and have used F-test to see that $\sigma_x^2$ $\neq$ $\sigma_y^2$ ...
limestreetlab's user avatar
1 vote
0 answers
25 views

How to estimate the confidence interval for a "predicted difference" from a quadratic model?

Assume you have past consumption levels $c_1, \dots c_n$ at times $t_1, \dots t_n$ and cumulated consumption levels $y_1=c_1, y_2 = c_1 + c_2, \dots y_n=\sum_{k=1}^{n} c_k$. (I use the quadratic term ...
Christoph's user avatar
  • 209

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