Linked Questions

69
votes
8answers
11k views

What is meant by a “random variable”?

What do they mean when they say "random variable"?
125
votes
3answers
133k views

What is the difference between a consistent estimator and an unbiased estimator?

I'm really surprised that nobody appears to have asked this already... When discussing estimators, two terms frequently used are "consistent" and "unbiased". My question is simple: what's the ...
45
votes
6answers
19k views

Intuitive explanation of the bias-variance tradeoff?

I am looking for an intuitive explanation of the bias-variance tradeoff, both in general and specifically in the context of linear regression.
38
votes
2answers
9k views

When is a biased estimator preferable to unbiased one?

It's obvious many times why one prefers an unbiased estimator. But, are there any circumstances under which we might actually prefer a biased estimator over an unbiased one?
21
votes
4answers
32k views

What is the relation between estimator and estimate?

What is the relation between estimator and estimate?
3
votes
1answer
6k views

What is the difference between Mean Squared Deviation and Variance?

I am doing some tutoring for an AS-Level maths student and unfortunately for me they are doing statistics. This is not my strong point, mainly from the point of view of remembering all of the ...
1
vote
2answers
631 views

When are OLS linear regression parameters inaccurate?

Q1: Show quantitatively that OLS regression can be applied inconsistently for linear parameters estimation. We show an example of linear OLS inaccuracy from inappropriate application to bivariate ...
0
votes
2answers
224 views

What is difference between statistical bias and common sense bias [closed]

Colloquially, a statistic may be described as “biased” if it misrepresents whatever it’s intended to represent, whether or not it was more likely a priori to err in one direction or another. (This ...
1
vote
1answer
99 views

Binary classification and target-label proportion

Suppose that we have a binary classification problem with a vector y = [1 1 0 1 0 0 1 ... 0] having the proportion: ...
1
vote
1answer
25 views

Unbiasedness property under trimmed data

Suppose we want to estimate a simple regression model by OLS and the selected model is the true model. Randomly trimming data does not change the unbiasedness property of the coefficient. However, ...