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6 votes
4 answers
590 views

What is the information in an exact p-value?

Consider the following two statistical principles: 1) an exact test's $p$-value gives the exact frequency with which the observed random sample appears by chance, i.e., under a true null hypothesis; ...
virtuolie's user avatar
  • 642
1 vote
1 answer
28 views

Why does the score test work for values longer in the tail that have a small log-likelihood derivative?

The score test says that we take the derivative of the log-likelihood at $H_0$ and divide it by the fisher information at $H_0$. $U(\theta )={\frac {\partial \log L(\theta \mid x)}{\partial \theta }}.$...
Estimate the estimators's user avatar
0 votes
0 answers
61 views

Fiding the test statistic, using wald test

Given the random sample $X_1,...,X_n \sim N(\mu, \sigma^2)$, I want to perform a Wald test for: $\mathrm{H}_\mathrm{0}: \mu = \mathrm{\mu}_\mathrm{0}$ $\mathrm{H}_\mathrm{1}: \mu \neq \mathrm{\mu}_\...
CORy's user avatar
  • 543
6 votes
2 answers
737 views

Is it true that we can always increase statistical power/estimator precision by increasing sample size?

Suppose a test has ~$16.67\%$ power to detect some arbitrary but fixed effect size when sample size is $3$, and as we increase size by adding IID random observations to the sample ${4, 5, 6, 7,...}$ ...
virtuolie's user avatar
  • 642
5 votes
2 answers
2k views

Statistical comparison of (covariance) matrices

I am trying to test whether the covariance matrix for the maximum likelihood estimates for a gaussian general linear model approaches the inverse Fisher information matrix (times 1/n , n being the ...
Meep's user avatar
  • 173
0 votes
0 answers
28 views

Does Fisher Information quantify precision? [duplicate]

Looking at perspective from estimating the actual value from a set of data measured by the instrument. Does Fisher information just quantify the precision of the measurement? What does it say about ...
Chetan Waghela's user avatar
1 vote
1 answer
601 views

Different version of Wald test statistic formula

I came across two formulas for the Wald test statistic in a maximum likelihood framework: One has $(R\hat{\theta}-r)'(RI_n^{-1}R')^{-1}(R\hat{\theta}-r)$, where $I_n^{-1}$ is the inverse of the ...
Guest's user avatar
  • 11
2 votes
0 answers
2k views

wald test and score test, normal or chi square?

I learnt from section 10.3 of statistical inference that both Wald test statistic $\frac{W_n-\theta_0}{S_n}\approx\frac{W_n-\theta_0}{\sqrt{\hat I_n(W_n)}}$ and score test statistic $\frac{S(\theta_0)}...
user3813057's user avatar
  • 1,102