Displaying 20 results from an estimated 500 matches similar to: "Non-linear maximization function in R"
2005 Feb 20
1
logistic regression and 3PL model
Hello colleagues,
This is a follow up to a question I posed in November regarding an analysis
I was working on. Thank you to Dr. Brian Ripley and Dr. John Fox for
helping me out during that time.
I am conducting logistic regression on data set on psi (ESP) ganzfeld
trials. The response variable is binary (correct/incorrect), with a 25%
guessing base rate. Dr. Ripley suggested that I
2009 Jul 03
1
The time series analysis functions/packages don't seem to like my data
I have hundreds of megabytes of price data time series, and perl
scripts that extract it to tab delimited files (I have C++ programs
that must analyse this data too, so I get Perl to extract it rather
than have multiple connections to the DB).
I can read the data into an R object without any problems.
thedata = read.csv("K:\\Work\\SignalTest\\BP.csv", sep = "\t", header
=
2012 Jan 04
1
Adding a vertical line to plot with two overlapping density plots
Hi,
A simple question I hope. I wish to add a single vertical line to a plot
with several density plots.
Here is a simplified example.
############
thedata <- data.frame(x1=rnorm(100,1,1),x2=rnorm(100,3,1)) #create data
thedata.m<-melt(thedata)
densityplot(~value, thedata.m, groups=variable,auto.key=list(columns=2))
#this gives the two density plots
#########
what I wish now is to add a
2008 Jul 16
1
Problem with mpi.close.Rslaves()
I am running R 2.7.0 on a Suse 9.1 linux cluster with a job scheduler
dispatching jobs and openmpi-1.0.1. I have tried running one of the
examples at http://ace.acadiau.ca/math/ACMMaC/Rmpi/examples.html in Rmpi
and they seem to be working, except mpi.close.Rslaves() hangs. The
slaves are closed, but the master doesn't finish its script. Below is
the example script and the call to R. The job is
2008 Nov 07
1
Rmpi task-pull
Hi, I'm testing the efficiency of the Rmpi package regarding parallelization
using a cluster.
I've found and tried the task pull programming method, but even if it is
described as the best method, it seems to cause deadlock, anyone could help
me in using this method?
here is the code I've found and tried:
# Initialize MPI
library("Rmpi")
# Notice we just say "give us
2006 Mar 11
2
how to create analog stripchart plots of x vs t (t=mm/dd/yyyy hh:mm:ss)
Hello r-experts,
I sure could us a little help.
I have an ever updating text file with timestamped data in it. I can
reformat in anyway I want if need be but currently I have chosen to make
columns of date, time and measuresed value (comma delimeted and with the
dates and times in quotes to interpret them as strings).
Here is a small section of my text data file:
2018 Jan 24
4
Geometry delaunayn and deldir results, differing results from Octave due to decimal precision?
The problem:
I would like to translate the Octave algorithm in griddata.m to R.
Within the griddata algorithm calls are made to the Delaunay function. For the R translation I have found delaunayn within the "geometry" package and also the deldir package.
Both do similar things but give slightly different results depending on the input.
The question is, what is making the results for the
2018 Jan 24
0
Geometry delaunayn and deldir results, differing results from Octave due to decimal precision?
"The question is, what is making the results for the R packages different
from each other?"
There are literally thousands of R packages, contributed independently by
thousands of people. There should be no expectation of consistency or for
that matter, "correctness", among them. Caveat emptor.
Only within the base R distribution, maintained and mostly written by the R
Core
2006 Jul 07
1
densityplot and panel.groups
I am trying to plot multiple densityplots on each panel, and using
panel.groups to do some additional plotting (not included in the
example) as in this example.
library(lattice)
thedata <- data.frame(x=rnorm(1200),class=rep(1:3,each=200,times=2),
group=rep(1:2,each=100,times=6))
densityplot(~x | class,groups=group,
xlab='x',
panel.groups =
2006 Feb 07
2
Question about Classes.
I have the attached class that I''m writing. The problem that I''m
running into is that I can not access the options from the createArray
function which get called after the ajax request gets done. I want to
move the values of the xml file to an array and story it in the options
variable. Can someone explain what I''m doing wrong?
var LeaderInfo = Class.create();
2008 May 02
3
data transformation
Dear all,
how can I, with R, transform a presence-absence (0/1) matrix of species
occurrences into a presence-only table (3 columns) with the names of the
species (1st column), the lat information of the sites (2nd column) and
the lon information of the sites (3rd column), as given in the below
example?
Thanks a lot for your help!
Christian
my dataframe:
site lat lon spec1 spec2 spec3 spec4
2007 Jul 06
2
access to 'formula' terms in a user function
This is probably buried somewhere in the R help archives, but I've been
unable to find it, so perhaps the keywords I use here will help bring the
topic to the surface more easily for future users.
I want to write my own modeling function (ultimately for some
multidimensional windowing - but this question is on scripting basics). For
purposes of figuring out my needs, lets just consider
2008 Jan 30
2
data.frame transformation
Dear all,
maybe somebody can provide some help for this problem:
Example:
I've got the following dataframe "data":
grid.id<-c(1:4)
lat<-c(10,12,13,15)
species1<-c(0,0,0,1)
species2<-c(1,1,0,0)
species3<-c(1,1,1,1)
data<-data.frame(cbind(grid.id,lat,species1,species2,species3))
How can I, out of "data" make a new dataframe, where the cells of value
2004 Jul 21
1
function ms
Dear R users,
I am using the MICE package. Specifically, at some point in my code I have
imp2=mice(PoptotalMICE,imputationMethod="logreg2")
And R returns...
iter imp variable
1 1 MICEYError in logitreg(xobs, yobs, intercept=F) :
couldn't find function "ms"
I have been looking for this ms function on the web, hoping it was just a matter of downloading a
2009 Nov 29
1
Convergence problem with zeroinfl() and hurdle() when interaction term added
Hello,
I have a data frame with 1425 observations, 539 of which are zeros. I
am trying to fit the following ZINB:
f3<-formula(Nbr_Abs~ Zone * Year + Source)
ZINB2<-zeroinfl(f3, dist="negbin", link= "logit", data=TheData,
offset=log(trans.area), trace=TRUE)
Zone is a factor with 4 levels, Year a factor with 27 levels, and
Source a factor with 3 levels. Nbr_Abs is counts
2007 Nov 09
1
fisher.test, chisq.test
Hi,
I want to analyse a contigency table (3 x 12) with a fisher.test
beacause there are cells that are less than 5.
?mmen Anken Baf Belchen H?chi Hof Porti R?m Schmutz Sch?n Sissa Tann
class14 7 26 150 2 46 68 126 66 3 31 7 61
class24 7 6 55 5 49 71 93 90 1 18 16 79
class34 1 1 4 3 19 8 29 61
2008 Jul 22
1
data transformation
Dear all,
how can I, with R, transform a presence-only table (with the names of
the species (1st column), the lat information of the sites (2nd column)
and the lon information of the sites (3rd column)) into a
presence-absence (0/1) matrix of species occurrences across sites, as
given in the below example?
Thanks a lot for your help!
Christian
My initial table:
species lat lon
sp1 10 10
2007 Aug 13
0
R^2 for multilevel models
Hi there,
In multiple regression one way to view R^2 is as (the square of) the
correlation between original y's and the estimated y's.
Suppose you fit a multilevel model with random intercept for each
cluster. Would it be valid to compute an R^2 by using fixed effects
plus the group intercepts to reduce the residuals?
I suspect this has been done and, given its absence from the lmer
2007 Oct 08
0
Residuals for binomial lmer fits
Dear all,
I would like to use the residuals in a general linear mixed effect model
to diagnose model fit.
I know that the resid function has been implemented for linear mixed
models but not yet for general linear mixed effects. Is there a way to
get them out of lmer fit objects?
I tried searching the r-help archive and found nothing.
I tried and failed to replicate what (I guessed would be
2006 Sep 14
1
working with strptime data
Dear R-forum,
I am looking for a good resource/help on working with POSIXct values and
controlling the pretty x-axis labels and tick marks for a data VS time
plots. Specifically, I wish to do programming logic which creates
different vertical ablines calculations based on the range of times
which i am working on. The default plot results are adequate, but I
would love to make explicit calls on