Questions tagged [bias]
The difference between the expected value of a parameter estimator & the true value of the parameter. Do NOT use this tag to refer to the [bias-term] / [bias-node] (ie the [intercept]).
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Cox proportional hazard model and non-randomly selected sample
Are there any methods to correct bias in Cox proportional hazard model caused by non-randomly selected sample (something like Heckman's correction)?
Background:
Lets say the situation looks as ...
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Omitted variable bias in time series
This is a brief question because my lecturer mentioned it today in class but I don't quite understand. Why is omitted variable bias not a major problem in time series analysis?
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Why is it claimed that a sample is often more accurate than a census?
When learning the course of sampling, I meet the following two statements:
1) Sampling error leads to mostly variability, nonsampling errors lead to bias.
2) Because of nonsampling error, a sample ...
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Can a coin be biased?
If I have a coin that is not necessarily expected to turn up heads half of the time, then is it correct to call the coin biased? Or does bias in statistics only mean the bias of an estimator in which ...
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Overmatching bias and confounding variables
As I understand it, matching is one way to identify causality in observational studies. By matching observations that are "similar" and comparing ones that did or did not receive treatment, you can ...
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Can the sample size of subgroups influence significance of correlations?
I am currently helping a friend with some statistical analysis.
There is a main hypothesis, for which a significant relationship can be shown. Lets call the predictor variable A and the predicted ...
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Removing human evaluator bias
I am working on machine translation evaluation, and am looking at ratings given by humans who are judging the quality of sentences produced by machine translation systems. The evaluators give fluency ...
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Is there a graphical representation of bias-variance tradeoff in linear regression?
I am suffering from a blackout. I was presented the following picture to showcase the bias-variance tradeoff in the context of linear regression:
I can see that none of the two models is a good fit - ...
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Difference among bias, systematic bias, and systematic error?
Is there any difference among the following terms or they are same?
Bias
Systematic bias
Systematic errors
If there exist some differences then, please explain them. Can these errors be reduced ...
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How to assess whether experimental measurements obtained from different technicians are biased?
Suppose I have a list of measurements from an experiment; for example,
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But I then learn that these experiments were conducted by two different technicians, so I ...
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Re-estimate classification model with biased data
Let's say that I score (with, for example, a logit model) a group of 10,000 customers according to their potential of buying a product, and that I decide to contact the top 1,000 with a special offer. ...
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What intuitively is "bias"?
I'm struggling to grasp the concept of bias in the context of linear regression analysis.
What is the mathematical definition of bias?
What exactly is biased and why/how?
Illustrative example?
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Assessing rater bias where one rater has given one very high rating and the remainder very low ratings
What is a good statistical test to check if there is a bias in judging in a situation that there is one judge that gave extreme scores (high score for one of the contestant and very low scores on the ...
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Bias in sampling for set intersections
Say I have 2 sets, $A$ and $B$ with $n_{A}$ and $n_{B}$ elements respectively, which I assume is known. I would like to estimate $| A \bigcup B |$ using samples of $\tilde{A} \subset A$ and $ \tilde{...
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Stambaugh bias definition
How would you go about explaining "Stambaugh Bias" in simple relatively non-technical language?
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