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3 votes
1 answer
55 views

is the likelihood ratio test "best" for finite samples?

Wikipedia says The Neyman–Pearson lemma states that this likelihood-ratio (lr) test is the most powerful among all level α alpha tests for this case. Is this only true for infinite sample sizes? Is ...
A Friendly Fish's user avatar
1 vote
0 answers
54 views

UMP two sided tests for exponential families

Consider a random variable $X$ with density $$f(x : θ) = C(θ)e^{η(θ)T(x)}h(x), θ ∈ Θ$$. Assume that $η(θ)$ is strictly increasing in $θ$ and that the family is full rank. Show that there will not be ...
user671269's user avatar
1 vote
1 answer
52 views

Show a composite test is the most powerful after deriving a similar most powerful simple test

Let $X$ be a real-valued random variable with density $f(x) = (2\theta x + 1 - \theta) \mathbb{1}(x \in [0,1])$ where $1$ here is the indicator function and $-1 < \theta < 1$. I am trying to ...
Featherball's user avatar
1 vote
1 answer
118 views

Does there always exist for n small, a non-chi-squared test-statistic for the likelihood-ratio (neyman-pearson, karlin-rubin), score, and wald-tests?

An additional reason that the chi-squared distribution is widely used is that it turns up as the large sample distribution of generalized likelihood ratio tests (LRT).[6] LRTs have several desirable ...
user avatar
0 votes
0 answers
711 views

Which to Use: Likelihood Ratio Test or Uniformly Most Powerful Test?

I've recently been learning about MPTs (most powerful tests), UMPTs (uniformly most powerful tests) and LRTs (likelihood ratio tests), and do not totally understand in which context the different ...
Academic005's user avatar
1 vote
0 answers
188 views

How to combine two independent likelihood ratio tests?

Let us know that a patient has one of disease A or B. Suppose that we run an experiment to find that the patient has disease A or disease B. The null hypothesis is that the patient has disease A and ...
Amir's user avatar
  • 21
0 votes
0 answers
276 views

Neyman-Pearson hypothesis testing and composite alternative hypothesis

I am in love with the idea of setting up a statistical test à la Neyman-Pearson when possible, because it is just so intuitive. Most of times, $H_0$ is some kind of point hypothesis, but $H_1$ is ...
marco's user avatar
  • 215
1 vote
0 answers
48 views

Finding the likelihood ratio to test which distribution has the largest mean

The problem: Let $X_1, \ldots, X_n$ and $Y_1, \ldots, Y_m$ be two i.i.d. samples drawn from $\mathcal{N}(\mu_x, \sigma^2)$ and $\mathcal{N}(\mu_y, \sigma^2)$, respectively. I wanna test $H_0: \mu_x \...
WHoZ's user avatar
  • 66
0 votes
0 answers
586 views

Proving a test is UMP for Uniformly distributed random variable

Let $X_1, X_2,..., X_n$ be a sample of size n from the PMF $$P_N(x) = {1 \over N},\ \ \ \ \ \ \ \ \ x = 1,2,...,N;N \in \mathbb{N} $$ Show that $$ \varphi(x_1, x_2, ..., x_n) = \begin{cases} 1 & ...
AxyuS's user avatar
  • 101
1 vote
1 answer
102 views

A basketball probability question using Neyman–Pearson lemma

It is known that the probability of a basketball player to make his first shot is $p=0.6$ A player argues that it does not matter if he made the previous shot or not his odds stays the same. We say if ...
Roi Hezkiyahu's user avatar
1 vote
0 answers
133 views

Hypothesis testing - Neyman-Pearson Lemma

While studying for my exam and practicing with old exams I came across this question. In the answer to part d) they mention that both coefficients are positive and hence for some c the test in part b) ...
Boyd Werkman's user avatar
0 votes
0 answers
287 views

Finding UMP test when testing a simple hypothesis against a composite hypothesis

Hi all I have question regarding the following when reading the notes on Page 5 here: http://www.ams.sunysb.edu/~zhu/ams571/Lecture8_571.pdf The question that I have is when the author showed how to ...
john_w's user avatar
  • 649
0 votes
1 answer
310 views

Constant value in Neyman Pearson lemma

To know the k value in Neyman Pearson lemma, do we need to know the alternate hypothesis. To what I understood (from articles like PenStateNotes), we could get value of k using null hypothesis and the ...
kg__'s user avatar
  • 63
1 vote
0 answers
110 views

Likelihood ratio test and sample statistics

Given a sample $\mathbf X =(X_1,...,X_n)$ from a parent random variable $X$, Neyman-Pearson's test for two point hypotheses $H_0$ and $H_1$ is the one defined by the critical region $$C=\left\{\mathbf ...
renyhp's user avatar
  • 121
9 votes
1 answer
732 views

Reproduce figure of "Computer Age Statistical Inference" from Efron and Hastie

The summarized version of my question (26th December 2018) I am trying to reproduce Figure 2.2 from Computer Age Statistical Inference by Efron and Hastie, but for some reason that I'm not able to ...
Francisco Fonseca's user avatar

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