Displaying 20 results from an estimated 6000 matches similar to: "Area under standard normal density"
2005 Nov 03
1
multidimensional integration not over a multidimensionalrectangle
Hi,
anyone knows about any functions in R can get multidimensional integration
not over a multidimensional rectangle (not adapt).
For example, I tried the following function f(x,n)=x^n/n!
phi.fun<-function(x,n)
{ if (n==1) {
x
}else{
integrate(phi.fun, lower=0, upper=x, n=n-1)$value
}
}
I could get f(4,2)=4^2/2!=8, but failed in f(4,3)=4^3/3! Thanks
Best,
Lynette
2006 Aug 16
3
fitting truncated normal distribution
Hello,
I am a new user of R and found the function dtnorm() in the package msm.
My problem now is, that it is not possible for me to get the mean and sd out of a sample when I want a left-truncated normal distribution starting at "0".
fitdistr(x,dtnorm, start=list(mean=0, sd=1))
returns the error message
"Fehler in "[<-"(`*tmp*`, x >= lower & x <= upper,
2002 Apr 19
4
Multidimensional scaling
A student of mine wants to use R to do some nonmetric multidimensional
scaling. According to the R FAQ, there's a package called pcurve that
computes multidimensional scaling solutions, but I was not able to locate
it the contrib page (I am a Windows user with R version 1.4.1). Can
anyone tell me whether it is possible to do nonmetric multidimensional
scaling with R, and if so, how?
John
2007 Jun 13
1
Normal and Poisson tail area expectations in R
I am interested in R functions for the following integrals / sums (expressed best I can in text) -
Normal: G_u(k) = Integration_{Lower limit=k}^{Upper limit=infinity} [(u -k) f(u) d(u)], where where u is N(0,1), and f(u) is the density function.
Poisson: G(lambda,k) = Sum_{Lower limit=k}^{Upper limit=infinity} [(x-k) p(x, lambda)] where P(x,lambda) is the Poisson prob function with parameter
2011 Mar 29
2
normal distribution and floating point traps (?): unexpected behavior
dear all,
here's a couple of questions that puzzled me in these last hours:
##### issue 1 qnorm(1-10e-100)!=qnorm(10e-100)
qnorm(1-1e-10) == -qnorm(1e-10)
# turns on to be FALSE. Ok I'm not a computer scientist but,
# but I had a look at the R inferno so I write:
all.equal(qnorm(1-1e-10) , -qnorm(1e-10))
# which turns TRUE, as one would expect, but
all.equal(qnorm(1-1e-100) ,
2007 Jun 25
3
How to shadow 'power' area?
Dear all,
Suppose I plot two normal distributions (A and B) side by side and add
vertical line which hipotheticaly represent alpha value; e.g.:
x <- seq(-3.5,5, length=1000)
y <- dnorm(x)
# Plot distribution A
plot(y~x, type='l',axes=F,xlab="",ylab="",lwd=2)
# Plot distribution B
y2 <- dnorm(x-1.5)
lines(y2~x,lwd=2)
# Plot vertical line for alpha value
2010 Oct 03
2
sampling from normal distribution
Hello
If i want to resampl from the tails of normal distribution , are these commans equivelant??
upper tail:qnorm(runif(n,pnorm(b),1)) if b is an upper tail boundary
or
upper tail:qnorm((1-p)+p(runif(n)) if p is the probability of each interval (the observatins are divided to intervals)
Regards
[[alternative HTML version deleted]]
2007 Jan 19
8
kate editor for R
Like kile for LaTeX, Linux/KDE's kate editor is an excellent editor for
R, with easy code submission to a running R process. Syntax
highlighting is good. I have not been able to figure out two things:
- how to automatically reformat a line or region of text using good
indentation rules (Emacs/ESS make this so easy by just hitting Tab while
the cursor is in a line, or highlighting a
2012 Jul 20
3
function for inverse normal transformation
Hi,
What is the function for inverse normal transformation?
Thanks,
Carol
[[alternative HTML version deleted]]
2019 Jun 21
4
Calculation of e^{z^2/2} for a normal deviate z
Hello,
Well, try it:
p <- .Machine$double.eps^seq(0.5, 1, by = 0.05)
z <- qnorm(p/2)
pnorm(z)
# [1] 7.450581e-09 1.228888e-09 2.026908e-10 3.343152e-11 5.514145e-12
# [6] 9.094947e-13 1.500107e-13 2.474254e-14 4.080996e-15 6.731134e-16
#[11] 1.110223e-16
p/2
# [1] 7.450581e-09 1.228888e-09 2.026908e-10 3.343152e-11 5.514145e-12
# [6] 9.094947e-13 1.500107e-13 2.474254e-14 4.080996e-15
2004 Feb 03
4
how to change one of the axis to normal probability scale
Hi,
I would like to plot a graph with one axis in log scale and the other in
normal probability scale using R. I cannot change the axis scale to
probability scale. What can be a solution? Thanks.
CT
2019 Jun 21
4
Calculation of e^{z^2/2} for a normal deviate z
You may want to look into using the log option to qnorm
e.g., in round figures:
> log(1e-300)
[1] -690.7755
> qnorm(-691, log=TRUE)
[1] -37.05315
> exp(37^2/2)
[1] 1.881797e+297
> exp(-37^2/2)
[1] 5.314068e-298
Notice that floating point representation cuts out at 1e+/-308 or so. If you want to go outside that range, you may need explicit manipulation of the log values. qnorm()
2019 Jun 23
2
Calculation of e^{z^2/2} for a normal deviate z
I agree with many the sentiments about the wisdom of computing very
small p-values (although the example below may win some kind of a prize:
I've seen people talking about p-values of the order of 10^(-2000), but
never 10^(-(10^8)) !). That said, there are a several tricks for
getting more reasonable sums of very small probabilities. The first is
to scale the p-values by dividing the
2008 Sep 09
2
densities with overlapping area of 0.35
Hi,
I like to generate two normal densities such that the overlapping area
between them is 0.35. Is there any code/package available in R to do that??
Regards,
Lavan
--
View this message in context: http://www.nabble.com/densities-with-overlapping-area-of-0.35-tp19384741p19384741.html
Sent from the R help mailing list archive at Nabble.com.
2002 May 09
2
truncated normal
Does anyone know of an R-function that will generate an observation from a
truncated normal (left or right) with a mu and sigma2? Any correspondence
would be greatly appreciated.
Best regards, Scott Summerill
FAA ACB-330
SIGNAL Corp.
609-485-6377
scott.ctr.summerill at tc.faa.gov
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read
2014 Nov 25
6
[Bug 10963] New: rsync to multiple destinations
https://bugzilla.samba.org/show_bug.cgi?id=10963
Bug ID: 10963
Summary: rsync to multiple destinations
Product: rsync
Version: 3.0.6
Hardware: All
OS: All
Status: NEW
Severity: normal
Priority: P5
Component: core
Assignee: wayned at samba.org
Reporter: Dave at
2006 Feb 08
1
Mixture normal distribution
Dear R helper,
I hope that u can help me to sort out my problem
because I sent an E-mail last night to R-list but I
have not receive any help and at the same time I think
this problem is not so hard.
I have used the following functions before
> K<-10
> prime<-c(2,3,5,7,11,13,17)
> UN<-seq(1:K)%*%t(sqrt(prime))
> U1<-UN-as.integer(UN)
> U<-matrix(qnorm(U1),K,7)
2009 Jun 05
2
ssh trouble checklist
Hi.
There should be a checklist of everything that can go wrong with
making an ssh connection.
Here's one entry for the list, which I didn't know before, and
* I couldn't see the problem from the -ddd and -vvv output, and
* there were no /var/log/* file entries to give hints.
Here's what I did
sudo kill <pid-of-sshd>
/usr/sbin/sshd
No good.
Usually I did kill
2007 Oct 31
3
Homework help: Is this how CIs of normal distributions are computed?
I'm looking for a function in R similar to t.test() which was generously
pointed out to me yesterday, but which can be used for normally
distributed data.
To recap yesterday:
> x <- scan()
1: 62 52 68 23 34 45 27 42 83 56 40
12:
Read 11 items
> alpha<- .05
> t.test(x)
One Sample t-test
data: x
t = 8.8696, df = 10, p-value = 4.717e-06
alternative hypothesis: true
2006 Mar 13
2
S-Plus Essentials April 24th-27th 2006
S-PLUS ESSENTIALS
24-27th April 2006
Venue : Insightful UK Office, Network House, Basing View, Basingstoke, Hants
RG21 4HG
We are pleased to be taking registrations for the next scheduled S-PLUS
Essentials course being held in Basingstoke 24-27th April 2006. If you are
unfamiliar with S-PLUS or have been meaning to upgrade your S-PLUS skills,
this is the course for you. This course will be