Displaying 20 results from an estimated 4000 matches similar to: "2D density tophat"
2012 Apr 17
1
Cummerbund differential expression data analysis package issue
Hi all,
I'm having the same issue as in this previous post:
http://r.789695.n4.nabble.com/R-error-td4200447.html#a4209042
And as another user of Biostar:
http://www.biostars.org/post/show/42562/cummerbund-isnt-managing-cuffdiff-database/#42895
Whereby I'm trying to output cuffdiff data into cummeRbund, but it appears
to be having issues with connection to a database (below). Does anyone
2007 Nov 26
2
2d Joint Density Plot
Hi all,
I'm fairly new to R, so I'm still trying to feel out what is available to
me. I would like to be able to plot joint density in a two dimensional plot
where density is indicated by color or darkness gradients, like a 2d color
coded topographic map. Ideally, the output would be something I could then
plot other points or lines on.
Currently, I'm calculating joint density with
2006 Jun 14
1
Estimate region of highest probabilty density
Estimate region of highest probabilty density
Dear R-community
I have data consisting of x and y. To each pair (x,y) a z value (weight) is assigned. With kde2d I can estimate the densities on a regular grid and based on this make a contour plot (not considering the z-values). According to an earlier post in the list I adjusted the kde2d to kde2d.weighted (see code below) to estimate the
2011 Nov 24
2
Question on density values obtained from kde2d() from package MASS
Hello,
I am a little bit confused regarding the density values obtained from the function kde2d() from the package MASS because the are not in the intervall [0,1] as I would expect them to be. Here is an example:
x <- c(0.0036,0.0088,0.0042,0.0022,-0.0013,0.0007,0.0028,-0.0028,0.0019,0.0026,-0.0029,-0.0081,-0.0024,0.0090,0.0088,0.0038,0.0022,0.0068,0.0089,-0.0015,-0.0062,0.0066)
y <-
2006 Apr 23
3
bivariate weighted kernel density estimator
Is there code for bivariate kernel density estimation?
For bivariate kernels there is
kde2d in MASS
kde2d.g in GRASS
KernSur in GenKern
(list probably incomplete)
but none of them seems to accept a weight parameter
(like density does since R 2.2.0)
--
Erich Neuwirth, University of Vienna
Faculty of Computer Science
Computer Supported Didactics Working Group
Visit our SunSITE at
2009 Dec 02
2
Joint density kde2d works improperly?
Dear all,
Please, look at the following code:
attach(geyser)
f1 <- kde2d(duration, waiting, n = 5)
a <- 0
for (i in 1:5){
for (j in 1:5){
a <- a + f1$z[i,j]
}
}
As far as I understood from Help kde2d returns matrix elements of which are
values of joint probability mass function Pr(X=x,Y=y) therefore, sum of its
elements should sum to 1.
Which is not the case from my check.
Where is
2005 Jul 22
1
virtual routing issue
A most puzzling network conundrum has arisen while I was attempting to
create a virtual network behind a virtual router which in turn connects the
virtual network to my real network.
My machine (192.168.103.23) is on the network with my router
(192.168.103.1). The virtual router, tiara, has to connect my
192.168.103.* network with the virtual 10.0.0.* network which comprises two
other virtual
2009 Mar 17
1
help with 3-D plot of kernel density estimates
Hi,
I guess I have a naive question. I use kde2d function in a standard way to
estimate kernel densities of x and y (x and y are vectors) and plot them
using image().
f1=kde2d(x,y)
image(f1)
But what if I want to see kernel estimates of three variables, x, y and z (a
vector) plotted together ? Something in which x<->y is plotted and colored
according to the corresponding value of z ?
2004 Nov 17
2
Cross-correlated variables in kernel density estimation
Hi,
I am wondering if the kde2d 2-D kernel density estimation function in the
MASS package can take into account the effect of correlations between the
variables. I couldn't find any achieved information on this issue.
Unfortunately, I don't have the 2002 edition of Modern Applied Statistics
with S by Venables and Ripley in case it was described there.
Thanks in advance.
Adam
2008 Jan 16
1
Probability weights with density estimation
I am a physician examining an NHANES dataset available at the NCHS
website:
http://www.cdc.gov/nchs/about/major/nhanes/nhanes2005-2006/demo_d.xpt
http://www.cdc.gov/nchs/about/major/nhanes/nhanes2005-2006/hdl_d.xpt
http://www.cdc.gov/nchs/about/major/nhanes/nhanes2005-2006/tchol_d.xpt
Thank you to the R authors and the foreign package authors in
particular. Importing from the SAS export
2006 May 11
1
Conditional contour plots for estimated density functions using Lattice
Does anybody here have a suggestion for a clever way of creating contour
plots for estimated bivariate density functions conditional on a factor?
The contourplot function in the 'lattice' package only accepts data that
are on the form 'z ~ x * y', not on the form 'x,y' or 'y~x'; otherwise I
could probably have used the panel function to do the needed conversion.
2010 Jul 28
1
kde on Torus
Hello,
I have 2D-data on a torus, i.e. they are scattered within [0:2pi) and are
supposed to be periodic with period 2pi.
Is there a way in R for a kernel density estimation for such data? I found this
article http://www.dmqte.unich.it/personal/dimarzio/density46.pdf
but
a) I don't fully understand the article (my knowledge in statistics is poor)
b) I did not understand which Eq.
2010 Nov 20
2
How to do a probability density based filtering in 2D?
Hello,
This sounds like a problem to which many solutions should exist, but I
did not manage to find one.
Basically, given a list of datapoints, I'd like to keep those within
the X% percentile highest density.
That would be equivalent to retain only points within a given line of
a contour plot.
Thanks to anybody who could let me know which function I could use!
Best,
Emmanuel
2012 Apr 18
1
ggplot2 stat_density2d issue.
Hello,
I'd be very grateful for help with some ggplot2's stat_density2d issues.
First issue is with data limits. xlim() and ylim() doesn't seem to
work; instead, estimates (and plotting) seems to be constrained to
range(x), range(y) no matter what i do. The documentation says i can
pass in kde2d's parameters to ... but pussing kde2d's "lims" parameter
achieves
2002 Dec 09
1
3D density estimation
I am trying to carry out density estimation for three dimensions
(with anywhere between a few hundred and ~8000 data points). Which
leads me to ask:
a) is there any equivalent to kde2d (in MASS) or bkde2D (in
KernSmooth) out there for three dimensions?
b) if not, my skills only seem to extend as far as writing a function
which measures density as the number of data points falling within a
2007 Aug 10
1
kde2d error message
Hello!
I am trying to do a smooth with the kde2d function, and I'm getting an error
message about NAs. Does anyone have any suggestions? Does this function
not do well with NAs in general?
fit <- kde2d(X, Y, n=100,lims=c(range(X),range(Y)))
Error in if (from == to || length.out < 2) by <- 1 :
missing value where TRUE/FALSE needed
Thanks in advance!!
Jen
[[alternative
2012 Nov 28
1
Plot 3d density
I want to create a 3d plot with densities.
I use the function density to first create a 2d dimensional plot for
specific x values, the function then creates the density and puts them
into a y variable. Now I have a second set of x values and put it
again into the density function and I get a second set of y variables
and so on.... I want to put those sets into a 3d plot, I hope you know
what I
2008 Jun 25
1
confidence bounds using contour plot
Hello
I'm trying to calculate 2d confindence bounds into a scatterplot using the
function "kde2d" (package MASS) and a contour plot.
I found a similar post providing a solution - unfortunatly I do not realy
understand which data I have to use to calculated the named "quantile":
Post URL: http://tolstoy.newcastle.edu.au/R/help/03b/5384.html
> (...)
>
>> Is
2003 Oct 22
1
2 D non-parametric density estimation
I have spatial data in 2 dimensions - say (x,y). The correlation
between x and y is fairly substantial. My goal is to use a
non-parametric approach to estimate the multivariate density describing
the spatial locations. Ultimately, I would like to use this estimated
density to determine the area associated with a 95% probability contour
for the data.
Given the strong correlation between x and
2010 Feb 15
4
density estimates for fixed points
Problem:
Based on a n x 2 data matrix i want a kernel estimate of the bivariate
density. However, i also wish to specify wich points the density should be
calculated at.
I can offcourse just write the full kernel density estimate as a R-code, but
surely there must already exist some package for this operation?
The package density(), seems to create a new matrix (depending on n), where
the