Displaying 20 results from an estimated 3000 matches similar to: "(no subject)"
2010 Apr 21
2
Maximum Likelihood Estimation in R
Dear R-Help,
I also send the following post by e-mail to you, however I try to post it
here aswell. My name is Henrik and I am currently trying to solve a Maximum
Likelihood optimization problem in R. Below you can find the output from R,
when I use the "BFGS" method:
The problem is that the parameters that I get are very unreasonable, I would
expect the absolute value of each
2009 Sep 30
1
Optim(...) estimate of stDev far too low
R-help,
I'm just trying to find the ML (maximum likelihood) estimates
of the mean and standard deviation of a set of observations:
>xx=c(2.5,3.5,4,6,6.5,7.5)
fn<-function(params,x=xx)
{
media<-params[1]
st <-params[2]
pdf=-sum(dnorm(log(xx),log(media),st,TRUE))
return(pdf)
}
optim(c(mu,stdev),fn,method="L-BFGS-B",lower=c(0.001, 0.001)
,upper = rep(Inf, 2),
2006 Mar 01
3
Optimization problem: selecting independent rows to maximize the mean
Dear R community,
I have a dataframe with 500,000 rows and 102 columns. The rows
represent spatial polygons, some of which overlap others (i.e., not
all rows are independent of each other).
Given a particular row, the first column contains a unique "RowID".
The second column contains the "Variable" of interest. The remaining
100 columns ("Overlap1" ...
2012 Aug 10
1
virtio-scsi <-> vhost multi lun/adapter performance results with 3.6-rc0
Hi folks,
The following are initial virtio-scsi + target vhost benchmark results
using multiple target LUNs per vhost and multiple virtio PCI adapters to
scale the total number of virtio-scsi LUNs into a single KVM guest.
The test setup is currently using 4x SCSI LUNs per vhost WWPN, with 8x
virtio PCI adapters for a total of 32x 500MB ramdisk LUNs into a single
guest, along with each backend
2012 Aug 10
1
virtio-scsi <-> vhost multi lun/adapter performance results with 3.6-rc0
Hi folks,
The following are initial virtio-scsi + target vhost benchmark results
using multiple target LUNs per vhost and multiple virtio PCI adapters to
scale the total number of virtio-scsi LUNs into a single KVM guest.
The test setup is currently using 4x SCSI LUNs per vhost WWPN, with 8x
virtio PCI adapters for a total of 32x 500MB ramdisk LUNs into a single
guest, along with each backend
2012 Nov 15
5
[Bug 57151] New: repeatable nouveau driver crashes/hangs during resume on Dell Latitude E6510 when drm.debug=14
https://bugs.freedesktop.org/show_bug.cgi?id=57151
Priority: medium
Bug ID: 57151
Assignee: nouveau at lists.freedesktop.org
Summary: repeatable nouveau driver crashes/hangs during resume
on Dell Latitude E6510 when drm.debug=14
QA Contact: xorg-team at lists.x.org
Severity: critical
Classification: Unclassified
2005 Nov 15
1
An optim() mystery.
I have a Master's student working on a project which involves
estimating parameters of a certain model via maximum likelihood,
with the maximization being done via optim().
A phenomenon has occurred which I am at a loss to explain.
If we use certain pairs of starting values for optim(), it
simply returns those values as the ``optimal'' values, although
they are definitely not
2010 Mar 31
2
Simplifying particular piece of code
Hello, everyone
I have a piece of code that looks like this:
mrets <- merge(mrets, BMM.SR=apply(mrets, 1, MyFunc, ret="BMM.AV120",
stdev="BMM.SD120"))
mrets <- merge(mrets, GM1.SR=apply(mrets, 1, MyFunc, ret="GM1.AV120",
stdev="GM1.SD120"))
mrets <- merge(mrets, IYC.SR=apply(mrets, 1, MyFunc, ret="IYC.AV120",
2013 Dec 15
0
[Bug 58378] [NV86] Distorted graphics on NVIDIA GeForce 8400M G after upgrade the kernel to 3.7.0 version
https://bugs.freedesktop.org/show_bug.cgi?id=58378
--- Comment #34 from Andreas Loew <awl1 at gmx.net> ---
Bad news once again...
I applied the following single-line patch to a stock 3.12.4 kernel in order to
switch to the NV50 fence:
diff -Nrpu linux-3.12.4.orig/drivers/gpu/drm/nouveau/nouveau_drm.c
linux-3.12.4/drivers/gpu/drm/nouveau/nouveau_drm.c
---
2023 Nov 03
2
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
Just a minor point in the suggested solution:
df$LAP <- with(df, ifelse(G=='male', (WC-65)*TG, (WC-58)*TG))
since WC and TG are not conditional, would this be a slight improvement?
df$LAP <- with(df, TG*(WC - ifelse(G=='male', 65, 58)))
-----Original Message-----
From: R-help <r-help-bounces at r-project.org> On Behalf Of Jorgen Harmse via
R-help
Sent: Friday,
2002 Feb 22
2
errors in integrate function?
I have been trying the integrate function in R, a function which would be
very useful for a current project of mine. But I am encountering errors
integrating the one function I have tried. The function to be integrated is
a product of a gamma demsity and a normal density:
gamma.by.normal_function(y,x,shape,scale,stdev)
return( dgamma(y,shape=shape,scale=scale)*
2023 Nov 03
1
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
Well, something like:
LAP <- ifelse(gender =='male', (WC-65)*TG, (WC-58)*TG)
The exact code depends on whether your variables are in a data frame or
list or whatever, which you failed to specify. If so, ?with may be useful.
Cheers,
Bert
On Fri, Nov 3, 2023 at 3:43?AM Md. Kamruzzaman <mkzaman.m at gmail.com> wrote:
> Hello Everyone,
> I have three variables: Waist
2023 Nov 03
1
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
df$LAP <- with(df, ifelse(G=='male', (WC-65)*TG, (WC-58)*TG))
That will do both calculations and merge the two vectors appropriately. It will use extra memory, but it should be much faster than a 'for' loop.
Regards,
Jorgen Harmse.
------------------------------
Message: 8
Date: Fri, 3 Nov 2023 11:10:49 +1030
From: "Md. Kamruzzaman" <mkzaman.m at gmail.com>
2023 Nov 03
1
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
Hello Everyone,
I have three variables: Waist circumference (WC), serum triglyceride (TG)
level and gender. Waist circumference and serum triglyceride is numeric and
gender (male and female) is categorical. From these three variables, I want
to calculate the "Lipid Accumulation Product (LAP) Index". The equation to
calculate LAP is different for male and females. I am giving both
2023 Nov 04
2
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
I might have factored the gender.
I'm not sure it would in any way be quicker. But might be to some extent
easier to develop variations of. And is sort of what factors should be
doing...
# make dummy data
gender <- c("Male", "Female", "Male", "Female")
WC <- c(70,60,75,65)
TG <- c(0.9, 1.1, 1.2, 1.0)
myDf <- data.frame( gender, WC, TG )
#
2023 Nov 05
1
I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
There are many techniques Callum and yours is an interesting twist I had not considered.
Yes, you can specify what integer a factor uses to represent things but not what I meant. Of course your trick does not work for some other forms of data like real numbers in double format. There is a cost to converting a column to a factor that is recouped best if it speeds things up multiple times.
The
2023 Nov 03
1
[EXTERNAL] RE: I need to create new variables based on two numeric variables and one dichotomize conditional category variables.
Yes, that will halve the number of multiplications.
If you?re looking for such optimisations then you can also consider ifelse(G=='male', 65L, 58L). That will definitely use less time & memory if WC is integer, but the trade-offs are more complicated if WC is floating point.
Regards,
Jorgen Harmse.
From: avi.e.gross at gmail.com <avi.e.gross at gmail.com>
Date: Friday,
2013 Dec 18
0
[Bug 58378] [NV86] Distorted graphics on NVIDIA GeForce 8400M G after upgrade the kernel to 3.7.0 version
https://bugs.freedesktop.org/show_bug.cgi?id=58378
--- Comment #55 from Andreas Loew <awl1 at gmx.net> ---
> > [aloew at aloew-lap envytools-master]$ ./nva/nvapoke 10200c 10
> > WARN: Can't probe 0000:01:00.0
> > PCI init failure!
> You need to run these as root.
Ouch - sorry - could have indeed had this idea myself... :-(
Here are the results as root:
[aloew at
2013 Dec 18
0
[Bug 58378] [NV86] Distorted graphics on NVIDIA GeForce 8400M G after upgrade the kernel to 3.7.0 version
https://bugs.freedesktop.org/show_bug.cgi?id=58378
--- Comment #57 from Ilia Mirkin <imirkin at alum.mit.edu> ---
(In reply to comment #55)
> > > [aloew at aloew-lap envytools-master]$ ./nva/nvapoke 10200c 10
> > > WARN: Can't probe 0000:01:00.0
> > > PCI init failure!
>
> > You need to run these as root.
>
> Ouch - sorry - could have indeed
2009 Aug 20
1
lattice xyplot strip colors and location
Hi all,
I've been trying (unsuccessfully) to modify an xyplot I created using the lattice package. I would like to change default strip colors and locations.
I started with numeric data in 4 columns, which look like this:
0.25 2 1 32
0.25 2 2 30
0.25 2 3 27
0.25 2 4 23
0.25 2 5 17
0.25 3 1 30
0.25