Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [elicitation]

11 questions
49
votes
6 answers

Eliciting priors from experts

How should I elicit prior distributions from experts when fitting a Bayesian model?
csgillespie
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What distribution can be closely (or precisely) fit to the "5 number summary" statistics?

I'm programming a web tool (="I'm a stats ignoramous who drifted here from stackoverflow.com") that allows scientists to enter predictions about the 5-number-summary stats for a variable. Entry is done using the UI-metaphor of a box-plot. I'd like…
Seth
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1 answer

How does one formalize a prior probability distribution? Are there rules of thumb or tips one should use?

While I like to think I have good grasp of the concept of prior information in Bayesian statistical analysis and decision making, I often have trouble wrapping my head around its application. I have in mind a couple of situations that exemplify my…
Phil
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2 answers

Reliability in Elicitation Exercise

I am trying to calculate the reliability in an elicitation exercise by analysing some test-retest questions given to the experts. The experts elicited a series of probability distributions which were then compared with the true value (found at a…
Amanda
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2 answers

Could prior elicitation by actually drawing the density of the prior be sensible? Has it been done/discussed?

Somebody mentioned, I don't remember who, that "there are many ways to specify the prior, you could even draw it!". It is clear to me that it is possible to actually draw the density of the prior using pen and paper and transform it into a histogram…
Rasmus Bååth
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Prior elicitation with Normal-Gamma or Normal-Inverse-Gamma

I am looking for a way to have experts elicit a prior for a Normal-Inverse-Gamma Bayesian linear regression model. Is there any material suggesting intuitive ways to go about this?
em70
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1 answer

Prior elicitation with Inverse Gamma and parametrization issue

This is a homework problem. I am very new to Bayesian conjugate analysis, so hang on with me. I have a sample $(x_1...x_n)$ of $n=20$ observations from an experiment. These observations are breakdown times for some machinery. The average of these…
Easymode44
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2
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1 answer

estimating beta parameter

I have data on 500 examinees with responses to 20 questions. Because the response is dichotomous, I use Beta(1,1) as the conjugate prior. Now I’m interested in using Beta(alpha, alpha) as the prior. How can I estimate alpha? I hope to do it in R.
Stephen Jung
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2
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1 answer

Combining triangular distributions

Vose (in Risk analysis a quantitative guide, 2008) argues that it is preferable to use non-parametric distributions when eliciting knowledge about an unknown distribution from experts. The argument is that experts may not be familiar with e.g. the…
Daniel C
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1 answer

Drawing inferences from multiple modal estimates of a random variable

I'm working to elicit a probability distribution from the Survey of Private Dealers, a ~monthly survey concerning the future direction of certain financial random variables. Latest example here. There are two tables regarding a single random…
MikeRand
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How to elicit prior distribution parameters?

A random sample of 300 women aged 60–69 years whose immediate families have had histories of cancer are to be screened for breast cancer. Let $y_i$ be 1 if woman i has a positive test, and 0 if not, for i = 1, . . . , 300. Let $\theta$ be the…
Günal
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