Displaying 20 results from an estimated 300 matches similar to: "optmizing with monotone stepfunctions?"
2004 Jul 12
3
Smooth monotone estimation on R
Hi all,
I'm looking for smooth monotone estimation packages, preferably using splines.
I downloaded the 'cobs' package and intend to use it, but since it offers only quadratic splines based on L1 minimization, I'd like to compare its performance to that of a more 'mainstream' cubic-spline, L2-norm minimizing spline. Preferably a smoothing spline.
Does anyone know of such
2005 May 08
4
Monotonic regression
Hi, I'm trying to find an implementation of monotonic regression in R
and I haven't been able to find anything that's really related to
this. isoMDS in the MASS package uses monotonic regression, however,
I was wondering if there is any standalone function for monotonic
regression?
Basically what I'm trying to do is implement monotonic regression
where I can see not just the
2009 Apr 17
1
Monotone Transformation
Hi, I am trying to use R to mimic what I did in SAS.
proc transreg data=x ;
model identity(GSI)=monotone(group1);
output out=d2 pprefix=M;
run;
Accroding to SAS documentation, the MONOTONE transfomation algorithm comes
from (Kruskal 1964, secondary approach to ties). I have tried ace. it does
provide some kind of monotone transformation, but it is not what I expected.
Here is how
2009 Aug 24
0
Monotone Smoothing specifically I splines
Hello
I am looking for a function to create an Integrated (I) spline basis,
somehting similar to the likes of 'bs' and 'ns'. I have come across the
funcitons,
fda::eval.monfd Values of a Monotone Functional Data
Object
fda::/.fd FDA internal functions
fda::monfn Evaluates a monotone function
fda::smooth.monotone
Monotone
2007 Dec 14
1
segfault isoreg with NAs
Dear list,
As can be seen below, adding a NA to the y values
in a call to isoreg results in a segfault.
ir4 <- isoreg(1:10, y4 <- c(5, 9, 1:2, 5:8, NA, 8))
Adding missing values to the x values, on the contrary,
gives an error, but maybe the error message could be
tailored to this particular situation.
y <- c(5, 9, 1:2, 5:8, 3, 8)
x <- c(1:9, NA)
isoreg(x, y)
## error message:
2004 Jan 28
3
unstability when using isoreg() function (PR#6494)
Full_Name: Petr Klasterecky
Version: 1.8.1
OS: Windows XP, Linux
Submission from: (NULL) (195.113.27.212)
The isoreg() function causes R to crash when called repeatedly. Consider the
following simple script:
{
library(modreg)
N <- 10
x <- rnorm(N)
print("Original x values:")
print(x)
for(n in (1:N)){print(y <- isoreg(x[1:n])$yf)}
}
I am able to run (call) it several
2016 Jul 14
0
[PATCH 2/5] Optimize fixed-point celt_fir_c() for ARM NEON
Create the fixed-point intrinsics optimization celt_fir_neon() for ARM NEON.
Create test tests/test_unit_optimization to unit test the optimization.
---
.gitignore | 1 +
Makefile.am | 39 ++++-
celt/arm/arm_celt_map.c | 17 +++
celt/arm/celt_lpc_arm.h | 65 ++++++++
celt/arm/celt_lpc_neon_intr.c
2001 Mar 12
2
Regressions with monotonicity constraints
This seems to be a recurrent topic, but I don't remember hearing a
definitive answer. I also apologies for cross-posting.
Say I have a numerical response variable and a bunch of multi-level factors
I want to use for modeling. I don't expect factor interaction to be
important so there will be no interactions in the model.
All this would be a perfect job for ANOVA except for one additional
2010 Jun 15
3
How to see how a function is written
Hello,
If I want to see how, say, apply function is written, how would I be
able to do that?
Just typing "apply" at the prompt does not work.
Thank you for help!
Sergey
2011 Jan 17
1
isoreg memory leak?
I believe there is a memory leak in isoreg in the current version of R,
as I believe the following shows
> gc()
used (Mb) gc trigger (Mb) max used (Mb)
Ncells 120405 3.3 350000 9.4 350000 9.4
Vcells 78639 0.6 786432 6.0 392463 3.0
> for(k in 1:100) {
+
+ y <- runif(10000)
+ isoreg(x,y)
+ }
> rm(x)
> rm(y)
> gc()
used (Mb) gc
2016 Jun 17
5
ARM NEON optimization -- celt_fir()
Hi all,
This is Linfeng Zhang from Google. I'll work on ARM NEON optimization in the
next few months.
I'm submitting 2 patches in the following couple of emails, which have the new
created celt_fir_neon().
I revised celt_fir_c() to not pass in argument "mem" in Patch 1. If there are
concerns to this change, please let me know.
Many thanks to your comments.
Linfeng Zhang
2017 Dec 11
1
OT -- isotonic regression subject to bound constraints.
Well, I could argue that it's not *completely* OT since my question is
motivated by an enquiry that I received in respect of a CRAN package
"Iso" that I wrote and maintain.
The question is this: Given observations y_1, ..., y_n, what is the
solution to the problem:
minimise \sum_{i=1}^n (y_i - y_i^*)^2
with respect to y_1^*, ..., y_n^* subject to the "isotonic"
2000 Aug 29
1
optmizing encoding
Is there any reason to avoid looking at optimizing the encoding process? From just a simple profile run, it looks like a big chunk of the time is in seed_curve, sqrt, dradf4 and log. Are there big changes to the encoding part that are coming that would invalidate optimizations done now?
-tim
--- >8 ----
List archives: http://www.xiph.org/archives/
Ogg project homepage:
2004 Dec 03
1
isotonic regression
Hi,
Has anyone written code for isotonic regression on ordered rectangular
grids?
Nathan
Nathan Leon Pace, MD, MStat
University of Utah
Salt Lake City, UT 84132
Office: 801.581.6393
Fax: 801.581.4367
Cell: 801.558.3987
Pager: 801.291.9019
Home: 801.467.2925
[[alternative text/enriched version deleted]]
2002 Dec 22
1
a maximazation question
Dear Sir/Madam:
this is shuangge Ma, graduate student in UW-Madison statistics department.
I have a computational question.
I have a function f(x,y). I want to find the y(x) that maximize f(x,y)
under the constraint y(x) is a non-decreasing step function.
Is there any R package or algorithm I can use for this purpose?
thanks a lot for your time and help,
Sincerely,
Shuangge Ma
2007 Jan 31
1
Estimation of discrete unimodal density
Dear All,
A method for the estimation is univariate unimodal densities (with unknown
mode) is described in "Statistical Inference under Order Restrictions" by
Barlow et al.. Would anyone know whether there is an R-implementation
(preferably with reference) for the estimation of univariate discrete unimodal
densities (with unknown mode)? Thanks in advance for your help.
Kind
2008 May 02
0
isotonic/ordered heterogeneity tests
dear R-help:
one of my students is struggling to test an ordered alternative
hypothesis on a set of groups (e.g., mu_a <= mu_b <= mu_c).
There has been some literature on this topic -- a lot of
this goes back to Bartholomew (1961); Gaines and Rice
(see refs below) are the ones who've popularized it in the
ecology community. The topic is closely related to isotonic regression,
but
2007 Oct 18
1
documentation bug for isoreg example (PR#10352)
Full_Name: Benjamin Tyner
Version: 2.6.0 (43063)
OS: WinXP
Submission from: (NULL) (171.161.224.10)
At the end of the examples for isoreg, there is
cat("R^2 =", formatC(sum(residuals(ir4)^2) / (9*var(y4)), digits=2),"\n")
I think this should be
cat("R^2 =", formatC(1 - sum(residuals(ir4)^2) / (9*var(y4)), digits=2),"\n"
Thanks
Ben
platform
2008 Jul 15
1
methods/namespaces/possible bug
Using
> methods("plot")
[1] plot.Date* plot.HoltWinters* plot.POSIXct*
[4] plot.POSIXlt* plot.TukeyHSD plot.acf*
[7] plot.data.frame* plot.decomposed.ts* plot.default
[10] plot.dendrogram* plot.density plot.ecdf
[13] plot.factor* plot.formula* plot.hclust*
[16] plot.histogram* plot.isoreg* plot.lm
[19] plot.medpolish*
2016 Jul 01
1
silk_warped_autocorrelation_FIX() NEON optimization
Hi all,
I'm sending patch "Optimize silk_warped_autocorrelation_FIX() for ARM NEON" in an separate email.
It is based on Tim’s aarch64v8 branch https://git.xiph.org/?p=users/tterribe/opus.git;a=shortlog;h=refs/heads/aarch64v8
Thanks for your comments.
Linfeng