Displaying 20 results from an estimated 8000 matches similar to: "Likelihood Ratio Tests"
2011 Sep 27
1
compare proportions
Hi, I have a seemingly simple proportional test. ?here is the question I am trying to answer:
?
There is a test running each day in the lab, the test comes out as
either positive or negative. So at the end of each month, we can calculate a
positive rate in that month as the proportion of positive test results. The
data look like:
?
Month??? ??# positive?????? # total tests??? positive rate
2011 Sep 07
4
suggestion for proportions
Hi, I am wondering if anyone can suggest how to test the equality of 2 proportions. The caveat here is that the 2 proportions were calculated from the same number of samples using 2 different tests. So essentially we are comparing 2 accuracy rates from same, say 100, samples. I think this is like a paired test, but don't know if really we need to consider the "paired" nature of the
2020 May 18
2
dbinom link
FWIW the link from ?dbinom to the Loader paper on Binomials is broken but the paper seems to be
available here: https://octave.1599824.n4.nabble.com/attachment/3829107/0/loader2000Fast.pdf
Roger Koenker
r.koenker at ucl.ac.uk<mailto:r.koenker at ucl.ac.uk>
Honorary Professor of Economics
Department of Economics, UCL
Emeritus Professor of Economics
and Statistics, UIUC
[[alternative
2020 May 18
3
dbinom link
In principle a good idea, but I'm not sure the whereabouts of Catherine Loader are known at this point. Last peeps from her on the net seem to be about a decade old.
.pd
> On 18 May 2020, at 10:31 , Abby Spurdle <spurdle.a at gmail.com> wrote:
>
> This has come up before.
>
> Here's the last time:
> https://stat.ethz.ch/pipermail/r-devel/2019-March/077478.html
2003 Apr 18
2
prop.test confidence intervals (PR#2794)
Full_Name: Robert W. Baer, Ph.D.
Version: 1.6.2
OS: Windows 2000
Submission from: (NULL) (198.209.172.106)
Problem: prop.test() does not seem to produce appropriate confidence intervals
for the case where the vector length of x and n is one. (I am not certain about
higher vector lengths.)
As an example, I include x=6 and n=42 which has a mean proportion of 0.115.
When I calculate the 95% CI
2008 Sep 23
4
Proper power computation for one-sided binomial tests.
Hi, I trying to determine the best way to compute the power for a
one-sample one-sided binomial test. Specifically I need to sample a
population of individuals and ask whether a sample rate of 0% is
compatable with a minimum threshold of 3% and how many samples are needed.
I have made use of power.prop.test but I am not sure if a) that is the
correct (or best) function to use and b) if the
2005 Jan 24
1
mcnemar.test odds ratios, CI, etc.
Does anyone know of another version of the Mcnemar test that provides:
1. Odds Ratios
2. 95% Confidence intervals of the Odds Ratios
3. Sample probability
4. 95% Confidence intervals of the sample probability
Obviously the Odds Ratios and Sample probabilities are easy to calculate
from the contingency table, but I would appreciate any help on how to
calculate the confidence
2011 Jul 07
4
Simulating from the null distribution of a 2 x 3 table
Dear all,
I want to simulate from the null distribution of the following 2 x 3 table,
2 5 10
4 8 5
I am using a chi-squared test.
Anyone has any idea how to do this?
--
Thanks,
Jim.
[[alternative HTML version deleted]]
2009 Apr 13
2
joint estimation of two poisson equations
Dear list members,
Is there a package somewhere for jointly estimating two poisson processes?
I think the closest I've come is using the "SUR" option in the Zelig
package (see below), but when I try the "poisson" option instead of
the "SUR" optioin I get an error (error given below, and indeed,
reading the documentation of the Zelig package, I get the impression
2007 Aug 02
1
simulate() and glm fits
Dear All,
I have been trying to simulate data from a fitted glm using the simulate()
function (version details at the bottom). This works for lm() fits and
even for lmer() fits (in lme4). However, for glm() fits its output does
not make sense to me -- am I missing something or is this a bug?
Consider the following count data, modelled as gaussian, poisson and
binomial responses:
counts
2006 Feb 03
5
pbinom with size argument 0 (PR#8560)
Full_Name: Uffe H?gsbro Thygesen
Version: 2.2.0
OS: linux
Submission from: (NULL) (130.226.135.250)
Hello all.
pbinom(q=0,size=0,prob=0.5)
returns the value NaN. I had expected the result 1. In fact any value for q
seems to give an NaN. Note that
dbinom(x=0,size=0,prob=0.5)
returns the value 1.
Cheers,
Uffe
2010 Jan 26
1
poisson.test from stats package does not pass the conf.level (PR#14195)
Hi,
The poisson.test function from stats package does not pass the conf.level p=
arameter for the two-sample test. Here is an example:
poisson.test(c(2,4),c(20,14),conf.level=3D.95)$conf.int
poisson.test(c(2,4),c(20,14),conf.level=3D.9)$conf.int
Here is the solution, change:
RVAL <- binom.test(x, sum(x), r * T[1]/(r * T[1] + T[2]),
alternative =3D alternative)
to:
2004 Jul 12
6
proportions confidence intervals
Dear R users
this may be a simple question - but i would appreciate any thoughts
does anyone know how you would get one lower and one upper confidence
interval for a set of data that consists of proportions. i.e. taking a
usual confidence interval for normal data would result in the lower
confidence interval being negative - which is not possible given the data
(which is constrained between
2011 Sep 22
2
Proportions of a vector
>
> Hi all,
> I have a vector xm say: xm = c(1,2,3,4,5,5,5,6,6)
>
> I want to return a vector with the corresponding probabilities based on the
> amount of times the numbers occurred. For example, I should get the
> following vector for xm:
> prob.xm = c(1/9, 1/9, 1/9, 1/9, 3/9, 3/9, 3/9, 2/9, 2/9)
>
Using prop.table gives:
Usage (with table)
> prob.xm <-
2002 Jul 06
3
one-sample binomial test
Hi everyone,
Here's how I solved a problem for my stats class. I'm pretty sure I
understand what's going on, but I wonder if there's a more direct way to
solve it.
Problem summary:
A recent poll indicated that Candidate A is leading B with 55% of the
vote. How many voters need to be surveyed to ensure a margin of error of
+/- 2.5% with 99% confidence.
Here's what I did:
2006 Jul 30
1
Power of a single sample binomial test
The only references to this I can find searching the archives are to a
student who asked in relation to his course work on a stats course.
Promise I'm not doing that!
I have a situation in which we want to test proportions against an
expected proportion, binom.test() is great. I'd like to do some post
hoc power tests (the x and n were beyond our control in the survey as
all we could set
2010 Jun 24
1
two sample binomial test
I wanted to know if there is a way to perform a two sample binomial test in
R. I know you can use the proportion test i.e.:
prop.test(c(19,5),c(53,39),p=NULL,alternative="two.sided"). But I was
looking to use the exact binomial test, binom.test, however when I have
tried replacing prop.test with binom.test I get an error. Is there any way
to do this?
--
View this message in context:
2009 Apr 20
1
doing zero inflated glmm for count data with fmr
Hello R users,
Doing My PhD I collected count data which I believe is zero inflated. I have
run a statistical model with lmer and family=poisson and got
summary(model)@sigma=1 so I believe there is no overdispertion. I would
like to use the fmr function from the 'gnlm' library but I just cannot
figure out from the examples in the help page and some forums out there how
to convert the lmer
2010 Sep 29
1
License of R manuals
Hi all,
Under what license are the R manuals (R language definition etc)
released? They are not mentioned explicitly in license() and have no
license information in the individual documents. Does this mean that
they are released under GPL-2? If so, what does that mean, given that
they aren't software?
Hadley
--
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics
2005 Apr 19
1
a statistic question,a bit off-topic,but important
it seems that all the existing prop test assume 2 independent or matched sample.but in the real world, many situations are not as we assume.for example,i do a research on the voter's prefernce through a random sampling.and the sample shows that 23% of the sample choose A,28% choose B,the others choose C.and i want to test the diference between the proportion choosing A and B (23%-28%=-5%) is