Displaying 20 results from an estimated 800 matches similar to: "Piecewise regression in lmer"
2003 Oct 09
1
Key-based auth fails - OpenSSH 3.7.1p2 (cygwin)
Hey all, Maybe someone has seen my problem before with OpenSSH under
cygwin. I'm trying to use key-based authentication and it's failing.
Configuration, permissions and -ddd information is provided in this email.
Thanks,
Brian Hayward
---------- Forwarded message ----------
Date: Thu, 9 Oct 2003 10:12:47 -0500 (CDT)
From: hayward at slothmud.org
To: cygwin at cygwin.com
Subject: Re:
2011 Jan 14
4
piecewise regression
Hello everybody!!!!
Quick question, if you'd like to throw a little tip:
does anyone knows a function that runs piecewise regression models with
coefficients estimation and inferences ?
Thank you
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2005 May 30
3
Piecewise Linear Regression
Hi,
I need to fit a piecewise linear regression.
x = c(6.25,6.25,12.50,12.50,18.75,25.00,25.00,25.00,31.25,31.25,37.50,37.50,50.00,50.00,62.50,62.50,75.00,75.00,75.00,100.00,100.00)
y = c(0.328,0.395,0.321,0.239,0.282,0.230,0.273,0.347,0.211,0.210,0.259,0.186,0.301,0.270,0.252,0.247,0.277,0.229,0.225,0.168,0.202)
there are two change points. so the fitted curve should look like
\
\ /\
2009 Mar 25
1
Piecewise
Hi,
I am a biologist (relatively new to R) analyzing data which we predict
to fit a power function. I was wondering if anyone knew a way to model
piecewise functions in R, where across a range of values (0-x) the data
is modeled as a power function, and across another range (x-inf) it is a
linear function. This would be predicted by one of our hypotheses, and
we would like to find the AICs
2012 Mar 25
2
Simple question regarding domain restrictions/piecewise functions in R
I am a novice R user.
I would like to be able to graph some simple piecewise functions/functions
with domain restrictions in R, but I'm having trouble defining such
functions. For example, I would like to define the following function:
f(x)={x^2 if -1<x<x; 1 if 2<x<3}
Notably, the function is undefined outside of domain (-1,1)U(2,3). My best
attempt in R is something like
2008 Jan 01
3
Specify a correct formula in R for Piecewise Linear Functions?
Dear all,
I have two variables, y and x. It seems that the relationship between them
is Piecewise Linear Functions. The cutpoint is 20. That is, when x<20, there
is a linear relationship between y and x; while x>=20, there is another
different linear relationship between them.
How can i specify their relationships in R correctly?
# glm(y~I(x<20)+I(x>=20),family = binomial, data =
2000 Jul 27
1
Interpolation using a piecewise linear function in higher dimensions
Dear all,
I am just wondering if anybody has implemented a function that can give a
piecewise linear interpolation in more than 2 dimensions?
I have looked at the akima package, but I would rather like a piecewise
linear interpolation rather than a spline and while it did the job quite
satisfactory for 2 dimensions, I need to interpolate in at least three
dimensions. If anybody has implemented
2001 Dec 05
4
Questions about piecewise spline fitting
Hi All,
I want to fit a piecewise spline of degree 1, i.e. a spline consisting of a
straight line over each piece. I downloaded the R package pspline, then I
have following questions:
1. in the program, the degree of the spline is specified by 2*norder-1. Why
do they adopt such scheme that we can only fit a spline with odd degree?
2. norder cannot be set to 1. Is there any specific reason
2007 May 08
1
Piecewise cubic Hermite interpolation
Which function implements the piecewise cubic Hermite interpolation?
I am looking for equivalent of matlab's interp1 with the method = 'pchip'
Here is the reference
http://www.mathworks.com/access/helpdesk/help/techdoc/index.html?/access/helpdesk/help/techdoc/ref/interp1.html&
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2012 Jun 05
1
Piecewise Lasso Regression
Hi All,
I am trying to fit a piecewise lasso regression, but package Segmented does not work with Lars objects.
Does any know of any package or implementation of piecewise lasso regression?
Thanks,
Lucas
2017 Jun 23
1
Piecewise continuous logistic regression with one knot
How can I fit a piecewise continuous logistic regression with a single free knot (i.e. the knot is not specified; the model produce an estimate of the value of the knot).
Thank you,
John
John David Sorkin M.D., Ph.D.
Professor of Medicine
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology and Geriatric Medicine
Baltimore VA Medical Center
2012 Apr 05
1
how to do piecewise linear regression in R?
Dear all,
I want to do piecewise CAPM linear regression in R:
RRiskArb−Rf = (1−δ)[αMktLow+βMktLow(RMkt−Rf)] + δ[αMkt High +βMkt High(RMkt −Rf )]
where δ is a dummy variable if the excess return on the value-weighted CRSP index is above a threshold level and zero otherwise. and at the same time add the restriction:
αMkt Low + βMkt Low · Threshold = αMkt High + βMkt High · Threshold
to ensure
2011 Jan 24
2
Problem with factor analysis
Hi all,
I am using the example on page 737 of "The R Book" by Michael J Crawley,
to plot factor loadings against each other (in a multivariate analysis).
However the following line code
plot(loadings(model)[,1],loadings(model)[,2],pch=16,xlab="Factor 1",
ylab="Factor 2")
throws an error message
"Error in plot.window(...) : need finite
2024 Jul 09
1
Automatic Knot selection in Piecewise linear splines
How can I do automatic knot selection while fitting piecewise linear
splines to two variables x and y? Which package to use to do it simply? I
also want to visualize the splines (and the scatter plot) with a graph.
Anupam
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2024 Jul 16
2
Automatic Knot selection in Piecewise linear splines
>>>>> Anupam Tyagi
>>>>> on Tue, 9 Jul 2024 16:16:43 +0530 writes:
> How can I do automatic knot selection while fitting piecewise linear
> splines to two variables x and y? Which package to use to do it simply? I
> also want to visualize the splines (and the scatter plot) with a graph.
> Anupam
NB: linear splines, i.e. piecewise
2008 Mar 24
1
Great difference for piecewise linear function between R and SAS
Dear Rusers,
I am now using R and SAS to fit the piecewise linear functions, and what
surprised me is that they have a great differrent result. See below.
#R code--Knots for distance are 16.13 and 24, respectively, and Knots for y
are -0.4357 and -0.3202
m.glm<-glm(mark~x+poly(elevation,2)+bs(distance,degree=1,knots=c(16.13,24))
+bs(y,degree=1,knots=c(-0.4357,-0.3202
2010 Apr 19
3
nls for piecewise linear regression not converging to least square
Hi R experts,
I'm trying to use nls() for a piecewise linear regression with the first
slope constrained to 0. There are 10 data points and when it does converge
the second slope is almost always over estimated for some reason. I have
many sets of these 10-point datasets that I need to do. The following
segment of code is an example, and sorry for the overly precise numbers,
they are just
2024 Jul 26
1
Automatic Knot selection in Piecewise linear splines
dear all,
I apologize for my delay in replying you. Here my contribution, maybe
just for completeness:
Similar to "earth", "segmented" also fits piecewise linear relationships
with the number of breakpoints being selected by the AIC or BIC
(recommended).
#code (example and code from Martin Maechler previous email)
library(segmented)
o<-selgmented(y, ~x, Kmax=20,
2010 Apr 16
2
piecewise nls?
I am looking into fitting a so-called double von Bertalanffy function to fish length-at-age data. Attempting to simplify the situation, the model looks like this ...
Y ~ f(X; a,b,c) if x < Z
Y ~ g(X; a,d,e) if x >= Z
where
* f and g are non-linear functions (the "traditional" "single" von Bertalanffy growth function),
* Y (length) and X (age) are observed variables,
2005 Mar 05
1
S-code for piecewise regression
Dear R-helpers,
a S-code for piecewise regressions was provided by Toms & Lesperance
(2003) Ecology, 84, 2034-2041 (paper can be found on the web).The code
is quite complete with different types of transitions around breakpoints
and model selection fonctions.
It doesn't work directly under R due to some "translation" problems I
guess. However I reckon that it would be a