Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 8719

Applied and theoretical statistics: e.g. statistical inference, regression, time series, multivariate analysis, data analysis, Markov chain Monte Carlo, design of experiments.

1 vote

refrence for simple statistics question: estimation of variance of $n$, for known $r=s+n$, f...

You could try a moment-matching approach. In particular, define $\hat{s}$ to be the value of $s$ such that $$\mbox{Pr}_{s}(-1 < r < 1) = \frac{\sum_i I(-1 < r_i < 1)}{N}$$ where $N$ is the number …
R Hahn's user avatar
  • 2,791
2 votes
Accepted

multivariate linear regression with dependent noise terms?

One key word would be "seemingly unrelated regressions" or SUR. The dependence of the noise term leads to different estimates of the regression coefficients (your $A$): http://en.wikipedia.org/wiki/S …
R Hahn's user avatar
  • 2,791
3 votes

Validate Wikipedia formula for Wishart conditioned on a conjugate prior

The distribution shown is not a Wishart distribution, it is a multivariate t-distribution. This is the marginal distribution of $X$ after integrating the covariance matrix out of the Gaussian sampling …
R Hahn's user avatar
  • 2,791
0 votes

Estimating the mean of a truncated gaussian curve

Others have hit on this, but I thought I'd contribute how I'd write the problem down (briefly): Let $x_i \sim N(m, 1)$ for $i \in \lbrace 1, \dots, N\rbrace$ and define $y_i \equiv x_i$ if $x_i > 0 …
R Hahn's user avatar
  • 2,791
2 votes
Accepted

Why is Beta the maximum entropy distribution over Bernoulli's parameter?

I think there are two separate things going on here. One is the issue of a maximum entropy distribution. The other is of whether or not distributions are invariant under different parameterizations. …
R Hahn's user avatar
  • 2,791
9 votes
Accepted

The difference between Principal Components Analysis (PCA) and Factor Analysis (FA)

The difference between PCA and FA can be thought of in terms of the underlying statistical models (regardless of estimation methods, although these will change depending on the model used). Consider …
R Hahn's user avatar
  • 2,791
5 votes
Accepted

Statistical calculations over algebraic structures

There is a whole research area called Algebraic Statistics, although its boundaries are pretty blurry in my opinion. But you could do worse than to start with Seth Sullivant's web page for some idea …
R Hahn's user avatar
  • 2,791
3 votes

Big ideas and big ways of thinking in statistics?

If a student walks away understanding the distinction between an estimand, an estimator and an estimate, along with the idea of a sampling distribution, you will have done an above average job. Equipp …
R Hahn's user avatar
  • 2,791
3 votes

Restate equality between random variables in a numerical stable way

If the $\mu_X(t)$ and $\mu_Y(t)$ are bounded for all values of $t$, we may try to construct a statistic that has a mean of $\mu_X(t)^2 - \mu_X(t)\mu_Y(t)$ for all $t$. Under the hypothesis, this mean …
R Hahn's user avatar
  • 2,791
3 votes

Strange pattern in rounding errors?

Apparently it's something to do with the "residuals" function in R. If you do this h <- fitted.values(lm(tan(c/2)~u)) plot(u,h-tan(c/2),ylim=c(-2e-16,2e-16),cex=0.1) instead (with the previous co …
R Hahn's user avatar
  • 2,791
1 vote

Gibbs sampler with linear constraints

I think the difficulty is worse than just finding the right algorithm. The first matter of business is deciding which conditional distribution you want to draw from, because they are non-unique. I'm …
R Hahn's user avatar
  • 2,791
11 votes

Distance metric between two sample distributions (histograms)

Total variation and Hellinger distance are two standard ways to measure this. Kullback-Leibler divergence is another standard way, as would be general $f$-divergences. The Earth-Mover's distance (al …
R Hahn's user avatar
  • 2,791
6 votes
Accepted

Why doesn't Stein effect happen for multinomial distributions?

This is not an answer, but maybe worth thinking about (and I cannot yet leave comments). My intuition about the Stein phenomenon is that while the individual coordinates of the Gaussian random variab …
R Hahn's user avatar
  • 2,791
1 vote
Accepted

Information criteria for ridge regression

The ridge estimator corresponds to the posterior mean under a Normal linear regression model with a conjugate Normal-inverse-gamma prior on the regression coefficients: $\beta \mid \sigma^2, \lambda …
R Hahn's user avatar
  • 2,791
5 votes
Accepted

Sampling uniformly from a sphere

The result you want, I think, is in Stationarity, Isotropy and Sphericity in $l_p^*$. It is behind a pay-wall, but the form of the distribution is stated in the abstract.
R Hahn's user avatar
  • 2,791

15 30 50 per page