Displaying 20 results from an estimated 5000 matches similar to: "(no subject)"
2006 Jan 19
2
function kde2d
Good evening,
I am Marta Colombo, student at Milan's Politecnico.
Thank you very much for your kindness, this mailing list is really useful.
I am using the function kde2d for two-dimensional kernel density estimation and I'd like to know something more about this kind of density estimator. In particular I'd like to know: what bandwidth is used ?
Thank you in advance for your attention
2008 Jul 08
1
fisher.test
Hi!
I am Marta Colombo, student in Mathematical Engineering at "Politecnico di Milano". For my master degree thesis I have to analyze some categorical data. My dataset is composed by 327 individuals and 16 variables. I am using Fisher exact test to test independence on IxJ contingency tables, but I have a problem with one variable.
R gives me this error message:
FEXACT error 7.
2005 Aug 18
1
display of a loess fitted surface
Good morning,
I am Marta Colombo,student at Politecnico,Milan. I am studying local regression models and I am using loess function. My problem is that when I have a loess object I don't know how to display the fitted surface; in fact, while in S when you have a loess object you can see it writing plot(object), in R this dosen't work. Also I'd like to know if there is something like the
2005 Aug 03
0
R-squared
Good evening, I am Marta Colombo, student of the "Politecnico" in Milan and I'm looking for some help.I'd like to know how I can see R-Squared using loess because in the output there are only:
number of observations
equivalent number of parameters
residual standard error
and even looking at the summary I wasn't able to find it.
Thank you very much for the attention,
Marta
2005 Nov 28
2
Robust fitting
Good evening,I am Marta Colombo, student of "Politecnico di Milano". I'm studying Local Regression Techniques such as loess, smoothing splines and kernel smoothers. Choosing "symmetric" for the argument "family" in loess function it is possible to produce a robust estimate , in function smooth.spline and ksmooth I didn't find this possibility. Well, is there a
2014 Jan 19
0
stat_density2d de ggplot2
Marta,
Puedes ver en el código source de ggplot stat_density si es que lo tienes
descargado como sorce o puedes ir a GitHub
https://github.com/hadley/ggplot2/blob/master/R/stat-density-2d.r y ver
como calcula los datos. Por lo que veo usa la función de la librería MASS
kde2d, para ver que hace esta escribe kde2d en la consola.
Espero te sirva.
Daniel
El 18 de enero de 2014, 22:35, marta
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
2004 Jul 05
1
how to personalize split function in rpart
Hallo!
I am a student of the Politecnico di Milano (Milan, italy) and I'm working
on CARTs. I'm trying to use the R rpart function with a personalized splitfunction... but I'm not able to do it!
More precisely, I would like to know what is the meaning of the function
'init', 'split' and 'eval' named in the help page.I can't find any answer
in
2007 Jun 07
0
How to get the number of modes using kde2d
Hi,
The silverman's paper introduction offer how to find a mode for one
dimensional data based
on software
http://www.stanford.edu/~kasparr/software/silverman.r,
for two dimensional data I use kde2d to smooth it out first, then I get a
matrix of densities for all the X(one dimension) cross Y(another
dimension).
I sort X and Y first before I pass the values to kde2d(x, y, c(hx, hy)),
the
2008 Apr 09
11
Number of words in a string
Hi R,
A quick question: How do we find the number of words in a string?
Example:
C="Have a nice day"
And the number of words should be 4. any built in function or?...
Thanks, Shubha
Shubha Karanth | Amba Research
Ph +91 80 3980 8031 | Mob +91 94 4886 4510
Bangalore * Colombo * London * New York * San José * Singapore * www.ambaresearch.com
This e-mail may contain
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
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
2008 Oct 04
0
difference between sm.density() and kde2d()
Dear R users,
I used sm.density function in the sm package and kde2d() in the MASS package
to estimate the bivariate density. Then I calculated the Kullback leibler
divergence meassure between a distribution and the each of the estimated
densities, but the asnwers are different. Is there any difference between
the kde2d and sm.density estimates? if there is a difference, then which is
the best
2004 Jul 23
0
AstriCon Update: Very Low Priced Ground Transport Available
-- GOOD NEWS! --
As ground transportation and the costs associated therewith are something of
an issue. So, in the spirit of making AstriCon available I've contacted the
hotel and arranged/discovered some low cost options:
-- MARTA --
MARTA, the Atlanta mass-transit system (i.e. train) can get you there. Take
MARTA from the airport north to the Brookhaven station. The hotel shuttle
will
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
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
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
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 <-
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
2014 Jan 30
2
objecto ggplot
Carlos,
mi intencion es entender el codigo:
https://github.com/woobe/blenditbayes/blob/master/2013-06-street-level-crime/analysis.R
Para luego hacer mi trabajo, algo similar a esto, pero adaptado a mi región.
Si te fijas en las lineas 141-161, esta esto:
## Convert the base map into a ggplot object
## All added Cartesian coordinates to enable more geom options later on
map.ggmap <-