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0 answers
9 views

How to deal with Bias Gradient Matrix for biased CRB(Cramér–Rao bound) calculation if the gradient matrix is m-by-n but $m \neq n$?

I am doing a model for collabrative localization and using the CRB(Cramér–Rao bound) as the localization performance measurement. I want to consider interference caused by NLOS and clutter, therefore ...
Loco Citato's user avatar
0 votes
1 answer
34 views

Expectation of reciprocal residual sum of squares

Consider an IID sample $X_1 , \cdots, X_n \in \mathbb{R}^d$, then what can we say about the expectation of the reciprocal residuals when projecting onto every other point? That is can we compute $$ E \...
mather's user avatar
  • 31
3 votes
1 answer
40 views

Can we get the conditional bias of the estimator at a generic $x$?

Consider a standard ERM problem based on quadratic loss where we solve $$ \hat{f}_n\in \operatorname*{arg min}_{f\in \mathcal{F}} R_\text{tr}(f) $$ where $R_\text{tr}(f)=\frac{1}{n}\sum_{i=1}^n (Y_i-f(...
H.Y Duan's user avatar
  • 173
4 votes
1 answer
188 views

Proving that the bias of the derivative of Parzen-Rosenblatt (kernel density) estimator is of order $O(h^2) $ and $O(h)$ when $h$ approaches $0$

I came across this property that I don't get and I couldn't find the proof anywhere: Suppose we have a density $K$ of the standard normal distribution and $K'$ its derivative. Suppose that the density ...
wageeh's user avatar
  • 241
7 votes
2 answers
449 views

How to prove unbiasedness/consistency/normality of an estimator that doesn't have a closed form?

My estimator looks like this: $$ \hat\theta(X) = \arg\max_{\theta} \frac1N \sum_{n=1}^N f(x_n|\theta) $$ Here, $f(x_n|\theta)$ is some arbitrary function: it's not a logarithm, and the sum is not a ...
ForceBru's user avatar
  • 330
3 votes
1 answer
619 views

What is an "unbiased forecast"?

Assume we estimate a model from the data $(X, Y)$, with some estimator $W(X, Y)$, which is estimating parameters $\theta$ for the model we chose. Then, we would like to perform a forecast for $Y_h$ ...
Artem Moskalev's user avatar
1 vote
0 answers
50 views

Bias in estimation of a latent / hidden variable drawn from a skewed distribution: what is it called?

I observe a bias effect in my measurement system that I can explain and correct using a simple latent or hidden variable model. I am sure this kind of effect has been described earlier in other fields ...
LudgerS's user avatar
  • 11
1 vote
1 answer
7k views

How to calculate the expected value of an estimator?

According to my book : An estimator, say, T, of the parameter $ \theta $ is said to be an unbiased estimator of $\theta$ if $ E\left( T\right) = \theta$. It then explains how to calculate $E\left( T\...
Positron12's user avatar
3 votes
1 answer
111 views

How can i find bias of estimator for specific value?

I have $X_1,...,X_n~ Ber(p)$ with MLE estimator $\hat p$ which is equal to sample mean. I need to find bias of estimator $\hat p(1 - \hat p)$ for $p(1-p)$. I presume $p(1-p)$ is variance of my RVs, so ...
Bet's user avatar
  • 33
1 vote
1 answer
131 views

What is the distinction between bias in prediction and parameter estimation?

I am trying to understand the distinction between bias in prediction and parameter estimation. This example in Gelman, Bayesian Data Analysis, 2nd ed. 2004 pp. 255-256 is very confusing to me. Why do ...
hatmatrix's user avatar
  • 869
3 votes
1 answer
3k views

Can bias of an estimate be decreased by increasing sample size?

I understand that in case of consistent estimates, larger the sample size, there's a higher probability that the estimate converges to true value of parameter. Now, using the sufficient condition of ...
Harry's user avatar
  • 1,387
2 votes
1 answer
356 views

VAR models vs univariate models

Suppose I know the true DGP is a VAR(1) process. Instead of fitting a VAR model, I can still fit univariate ARMA models to each of its components. Does anyone know whether it will result in biased ...
shani's user avatar
  • 681
2 votes
0 answers
105 views

Estimation and hypothesis testing for the difference in squared bias for two random variables

My Question: Let $X_t$ and $Y_t$ denote two time-series random variables, both of which are estimates of the random variable $\theta_t$. Let $U_t = X_t - \theta_t$, and $V_t = Y_t - \theta_t$. The ...
Colin T Bowers's user avatar
0 votes
0 answers
13 views

How to interpret an estimation system that predicts individual measurement poorly but provides unbiased mean?

I am trying to develop an automatic system to use machine to measure or estimate the length of a certain species. The system output gives quite strange result (figure below): From a regression point ...
tiantianchen's user avatar
  • 2,121
1 vote
1 answer
253 views

Show that bias term involving an indicator function convergences to zero

Assume that we have $N$ observations of i.i.d. data $(Y_i,X_i)_{i=1}^{N}$. We want to learn the model given by $Y=f(X)+\epsilon$. We use the data to estimate $\hat{f}$ using any machine learning ...
adam's user avatar
  • 115

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