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Tagged Questions

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1answer
97 views

Signal model classification between two possbile candidates

How to decide the most possible signal model between two model candidates besed on the received signal vector? Assume the received signal vector is $y$, the possible signal model …
2
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0answers
103 views

Worst-case error and Cramer-Rao Lower Bound - is there any mathematical relation between them?

I would like to understand the relation (if any) between the Cramer-Rao Lower Bound of estimation theory and the following simple definition of "reconstruction accuracy" which does …
1
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0answers
243 views

Definition and Convergence of Iteratively Reweighted Least Squares

I've been using iteratively reweighted least squares (IRLS) to minimize functions of the following form, $J(m) = \sum_{i=1}^{N} \rho \left(\left| x_i - m \right|\right)$ where $N …
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0answers
120 views

Better estimate than Sample mean?

Today I came a cross an old math thing I did some years ago. I remembered that I didn't find a similar result from anywhere at that time but forgot the thing altogether. So now I w …
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2answers
425 views

Estimating a sum

Sorry for the vague title but I couldn't find a better one. I want to compute the sum $S = \frac{1}{N}\sum_{i=1}^N c_i x_i$ where $c_i$s are known positive constants. The problem …
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0answers
35 views

Optimal rate of convergence of estimators in Sobolev space

I trying to find a reference on the optimal rate of convergence in Sobolev space. Given a regression model on interval $[0,1]$ $$ Y_{i}=f(x_{i})+\epsilon_{i},\ i=1,\ldots,N $$ wit …
0
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0answers
86 views

What are Effective Regression Techniques for Linguistic Analysis of Linked Data?

I am in the early stages of a problem that involves parsing a large number ($\approx 5 \times 10^9$) of documents (web pages) and estimating values from them. In particular I need …
0
votes
1answer
92 views

Estimation of Temporal Correlation of Signal

I have a signal and i'd like to estimate its temporal correlation. My limited understanding is i should compute the PSD by estimation using a parametric model such as AR. However …
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0answers
104 views

how to choose a better estimator [closed]

Vectors y1 and y2 are estimators of y, both of which are unbiased. Is there any criteria to decide which one is better? There isn't any measured values for y1, y2 and y so I can't …
1
vote
1answer
163 views

Is an unbiased estimator with arbitrarily small variance necessarily consistent?

Given an unbiased estimator $\hat \theta_n$ of a parameter $\theta$, if the estimator has small variance (approaching $0$ as $n\to\infty$), it seems reasonable to expect that the e …
0
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0answers
134 views

Maximum likelihood estimation [closed]

I have a bag with some marbles inside and we know (or are limiting our consideration to the possibility) that only red, green, and blue marbles exist. I sampled a few times (each w …
1
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2answers
1k views

Maximum likelihood estimator for Power-law with Exponential cutoff

Hi, for fitting empirical data to power-law I am aware of the work by Clauset et al. (http://arxiv.org/abs/0706.1062) and how to use maximum likelihood estimation. There exists a …
1
vote
1answer
180 views

A random censored regression problem?

Hello, Assume I have random variables $X$ and $Y$. $X$ is observable; $Y$ is not. We also know that, if $X \leq Y$, $Z = f(X,Y)$ where $Z$ is a third random variable and $f(\cdot) …
0
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0answers
347 views

Standard error of estimator is the same as standard error of difference of estimator and parameter?

I was reading through some notes deriving the different variances for confidence and prediction in OLS. Before dwelving into it though, the notes say that the standard error of $b_ …
0
votes
0answers
72 views

Estimation of X in Gaussian noise

Given $\textbf{x}=[x_1 x_2 ... x_n]^T$ where $\textbf{x} \in \{ 0, a_1, a_2, a_3\}^n, a_i \in \mathbb{C}$ and $\textbf{z} = \{z_1 z_2,...,z_n \}$ where $z_i \textbf{~} N(0,\sigma^ …

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