similar to: P values in non linear regression and singular gradients using nls

Displaying 20 results from an estimated 20000 matches similar to: "P values in non linear regression and singular gradients using nls"

2008 Aug 02
3
Bubble plots
Is there a way to create a 'bubble plot' in R? For example, if we define the following data frame containing the level of y observed for 5 patients at three time points: time<-c(rep('time 1',5),rep('time 2',5),rep('time 3',5))
2003 Mar 08
0
RE: Text Rotation (was: Take care with codes()!)
I've just uploaded gregmisc_0.8.2.tar.gz to CRAN. It should show up in the package repository in a day or two. This version of the gregmisc package provides an enhanced 'balloonplot' function with 'rowsrt', 'colsrt' arguments to control rotation of the labels, and 'rowmar', 'colmar' to control the amount of space reserved for the labels. Here's
2008 Aug 04
0
Unexpected nls behaviour: Solved
Hi Everyone, I'd omitted the non-optional 'parameters' argument to selfStart. Making this change to SSbatch gives the same (successful) result from the two calls to nls. SSbatch<-selfStart( model=function(Batch, Coeffs) { Coeffs[Batch] } ,initial=function(mCall, data, LHS) { # Estimate coefficients as mean of each batch xy <- sortedXyData(mCall[["Batch"]],
2008 Aug 01
0
Unexpected nls behaviour
Hi everyone, I thought that for a selfStart function, these two should be exactly equivalent > nls(Aform, DF) > nls(Aform, DF, start=getInitial(Aform, DF)) but in this example that is not the case in R (although it is in S-plus V6.2) ------------------------------ SSbatch<-selfStart( model=function(Batch, Coeffs) { Coeffs[Batch] } ,initial=function(mCall, data, LHS) { # Estimate
2006 Jul 03
1
xlab, ylab in balloonplot(tab)?
I'm not understanding something. I'm trying to add xlab & ylab to a balloon plot of a table object. From docs I thought following should work: require(gplots) # From balloonplot example: # Create an example using table xnames <- sample( letters[1:3], 50, replace=2) ynames <- sample( 1:5, 50, replace=2) tab <- table(xnames, ynames) balloonplot(tab)
2010 Feb 09
1
question about nlme...
I am looking for R code to be able to fit a linear-linear piecewise model with person-specific changepoint. I have searched the web, but have not been able to locate any code. Below is my attempt at some code: chgpt = function(a1,a2,a3,gam,wave){ yht=numeric(10) y1=(wave <= gam)*(a1+(a2*wave)) y2=(wave > gam)*((a1+(a2-a3)*gam)+a3*wave) yhat=y1+y2 return(yht) } nl.dat <- nlme(y ~
2000 Jan 05
0
bug in glm.fit (PR#395)
Dear R-team There seems to be a bug in glm.fit - I got the following error message: > > > + Error in names<-.default(*tmp*, value = ynames) : names attribute must be the same length as the vector In addition: Warning messages: 1: fitted probabilities of 0 or 1 occurred in: (if (is.empty.model(mt)) glm.fit.null else glm.fit)(x = X, y = Y, 2: fitted probabilities of 0 or 1 occurred
2005 Jun 22
2
A polar.plot BUG in plotrix 1.3.3 ?
Hi, I just updated to R-2.1.1 and updated packages acordingly However, after the update, routines that use polar.plot did not function as correctly. In plotrix 1.3.3 the polar.plot function does scale label.pos to radians prior to calling radial.plot Hence, the command polar.plot(c(5,10,5,0),c(-10,0,10,20),rp.type='P',
2003 Jan 22
1
something wrong when using pspline in clogit?
Dear R users: I am not entirely convinced that clogit gives me the correct result when I use pspline() and maybe you could help correct me here. When I add a constant to my covariate I expect only the intercept to change, but not the coefficients. This is true (in clogit) when I assume a linear in the logit model, but the same does not happen when I use pspline(). If I did something similar
2000 May 01
1
GAMs under R?
At 06:09 AM 5/1/00 +0100, Prof Brian D Ripley wrote: >On Sun, 30 Apr 2000, Stephen R. Laniel wrote: > >> I was just now surprised to note that functions to go generalized additive >> models don't appear to exist under R 1.000. In particular, the gam() and >> loess() functions aren't there. Are they hidden somewhere and I just >> haven't noticed? >
2010 Apr 19
1
BRugs
Hi. I am new here, and I am writing this Winbugs code with BRugs. n=length(bi.bmi) Lagegp=13 Lgen=2 Lrace=5 Lstra=15 Lpsu=2 #model gen x race bi.bmi.model=function(){ # likelihood for (i in 1:n){ bi.bmi[i]~ dbern(p[i]) logit(p[i])<- a0 + a1[agegp[i]]+a2[gen[i]]+a3[race[i]] + a12[agegp[i], gen[i]] + gam[stra[i]]+ u[psu[i],stra[i]] } # constraints for a1, a2, a3, a12 a1[1]<-0.0
2013 Jun 18
0
Fwd: offset en bucle
Amigos de la erre. He creado mi primer bucle con for para entrenar unos modelos con GAM. La respuesta es quasipoisson porque estoy trabajando con densidades de peces. Sin embargo, tengo un problema, no se muy bien como añadir el offset a la formula siguiente cuando creo el bucle. GAM.A1 <-gam ((DYO)~s(DMA,k=4)+ s(WOD,k=4)+s(CIN,k=4)+s(DRA,k=4)+s(DBR,k=4)
2012 Apr 02
1
gamm: tensor product and interaction
Hi list, I'm working with gamm models of this sort, using Simon Wood's mgcv library: gm<- gamm(Z~te(x,y),data=DATA,random=list(Group=~1)) gm1<-gamm(Z~te(x,y,by=Factor)+Factor,data=DATA,random=list(Group=~1)) with a dataset of about 70000 rows and 110 levels for Group in order to test whether tensor product smooths vary across factor levels. I was wondering if comparing those two
2010 Dec 08
1
I want to get smoothed splines by using the class gam
Hi all, I try to interpolate a data set in the form: time Erg 0.000000 48.650000 1.500000 56.080000 3.000000 38.330000 4.500000 49.650000 6.000000 61.390000 7.500000 51.250000 9.000000 50.450000 10.500000 55.110000 12.000000 61.120000 18.000000 61.260000 24.000000 62.670000 36.000000 63.670000 48.000000 74.880000 I want to get smoothed splines by using the class gam The first way I tried , was
2013 Jun 18
2
offset en bucle
Amigos de la erre. He creado mi primer bucle con for para entrenar unos modelos con GAM. La respuesta es quasipoisson porque estoy trabajando con densidades de peces. Sin embargo, tengo un problema, no se muy bien como añadir el offset a la formula siguiente cuando creo el bucle. GAM.A1 <-gam ((DYO)~s(DMA,k=4)+ s(WOD,k=4)+s(CIN,k=4)+s(DRA,k=4)+s(DBR,k=4)
2006 Mar 23
1
gam y-axis interpretation
Sorry if this is an obvious question... I'm estimating a simple binomial generalized additive model using the gam function in the package mgcv. The model makes sense given my data, and the predicted values also make sense given what I know about the data. However, I'm having trouble interpreting the y-axis of the plot of the gam object. The y-axis is labeled "s(x,2.52)"
2009 Apr 28
0
problems in package gam
Hi all, until now I have generally used mgcv for gams, however, I decided to experiment with the package gam, and have ran into the previously outlined problem (see below), for which I have not yet found a solution in the archives. If anyone has any suggestions, please let me know. The only difference for my case is that I am running R 2.9.0 under windows Thank you! I'm running R
2008 Aug 19
0
environment problems
Hello, I realize this is not a new problem, but I'm hoping somebody can point me in the right direction. The function silly() below calls gam() (from package gam) with different values of the span parameter for lo(), which is used inside the formula of gam. The values for span are stored in a vector that resides in the function silly(), and that lo(), for some reason, needs to see. A hack
2012 May 23
0
gam (mgcv) vs. multiple regression breakpoint analysis: inconsistencies?
Dear useRs, I have a question with respect to fitting a non-linearity using gam (mgcv package, version 1.7-16). In a study I'm currently conducting, I'd like to find out if there is a breakpoint after which the effect of Age of Acquisition (AOA) of the second language changes. I.e. if the slope of AOA before the breakpoint (at a certain AOA) is different from the slope past the
2008 Feb 28
0
use of step.gam (from package 'gam') and superassignment inside functions
Hello, I am using the function step.gam() from the 'gam' package (header info from library(help=gam) included below) and have come across some behavior that I cannot understand. In short, I have written a function that 1) creates a dataframe, 2) calls gam() to create a gam object, then 3) calls step.gam() to run stepwise selection on the output from gam(). When I do this, gam()