Displaying 20 results from an estimated 3000 matches similar to: "maximum difference between two ECDF's"
2004 Dec 22
0
weighted kernel density estimation
Dear wizaRds,
I use the MASS::kde2d function to estimate density of the two first 
principal components. I do that to have a graphic visualisation of a 
"group structure" in my dataset. So far, no problem.
But i would like to estimate that density using weights according to the 
COS?? values that tells me if my observation is well represented on the 
factorial plan 1-2. I would like to
2009 Mar 25
1
Confusion about ecdf
Hi,
I'm bit confused about ecdf (read the help files but still not sure about
this).  I have an analytical expression for the pdf, but want to get the
empirical cdf.  How do I use this analytical expression with ecdf?
If this helps make it concrete, the pdf is:
f(u) = \sum_{t = 1}^T 1/n_t \sum_{i = 1}^{n_t} 1/w K((u - u_{it})/w)
where K = kernel density estimator, w = weights, and u_{it} =
2013 Jul 02
0
Optimización MINLP
Muy buenas,
Tengo la siguiente duda/problema,
He optimizado con éxito un problema de este tipo:
\sum f(x_i)
donde f es una curva exponencial (función no lineal)
sujeto a:
a_i < x_i < b_i
y
\sum f(x_i) < Presupuesto
Vamos, es repartir un presupuesto forzando a que inviertas como poco a_i y
como mucho b_i para cada i
Esto lo hecho correctamente usando el paquete:
2006 Dec 08
1
MAXIMIZATION WITH CONSTRAINTS
Dear R users, 
I?m a graduate students and in my master thesis I  must 
obtain the values of the parameters x_i which maximize this  
Multinomial log?likelihood function
log(n!)-sum_{i=1]^4 log(n_i!)+sum_
{i=1}^4 n_i log(x_i)
under the following constraints:
a) sum_i x_i=1, 
x_i>=0, 
b) x_1<=x_2+x_3+x_4
c)x_2<=x_3+x_4
I have been using the 
?ConstrOptim? R-function with the instructions
2009 May 16
1
maxLik pakage
Hi all;
I recently have been used 'maxLik' function for maximizing G2StNV178 function with gradient function gradlik; for receiving this goal, I write the following program; but I have been seen an error  in calling gradient  function;
The maxLik function can't enter gradlik function (definition of gradient function); I guess my mistake is in line ******** ,that the vector  ‘h’ is
2008 Dec 26
2
Computational Probability
Hi
Firstly , happy Christmas to R-Help! Secondly, I wonder if anyone can help
me with the following query: I am trying to reproduce some explicit
probability calculations performed in APPL (a Maple extension for
computational probability). For instance, in APPL, to compute the
probability that the sum of 10 iid uniform variables [0,1] will be between 4
and 6, (i..e Pr( 4 < \sum_{i=1}^{10}X_i
2004 Dec 15
2
how to fit a weighted logistic regression?
I tried lrm in library(Design) but there is always
some error message. Is this function really doing the
weighted logistic regression as maximizing the
following likelihood:
\sum w_i*(y_i*\beta*x_i-log(1+exp(\beta*x_i)))
Does anybody know a better way to fit this kind of
model in R?
FYI: one example of getting error message is like:
> x=runif(10,0,3)
> y=c(rep(0,5),rep(1,5))
>
2005 Jun 15
2
need help on computing double summation
Dear helpers in this forum,
   This is a clarified version of my previous
questions  in this forum. I really need your generous
help on this issue.
> Suppose I have the following data set:
> 
> id x y 
> 023 1 2
> 023 2 5
> 023 4 6
> 023 5 7
> 412 2 5
> 412 3 4
> 412 4 6
> 412 7 9
> 220 5 7
> 220 4 8
> 220 9 8
> ......
> 
Now I want to compute the
2010 Feb 09
0
Kernel density / weights matrix?
Dear everyone,
I'm coding the Horowitz-Spokoiny (2001) test [1], and I would be very
grateful or some advice regarding the Kernel density (apologies
beforehand if my terminology is not fully correct). I have looked into
ksmooth and npreg, but with no success. 
Given a (n x p) matrix of covariates X, I need to construct the
following matrix of Kernel densities or weights:
w(x_i, x_j) = 
	
2006 May 24
1
(PR#8877) predict.lm does not have a weights argument for
I am more than 'a little disappointed' that you expect a detailed 
explanation of the problems with your 'bug' report, especially as you did 
not provide any explanation yourself as to your reasoning (nor did you 
provide any credentials nor references).
Note that
1) Your report did not make clear that this was only relevant to 
prediction intervals, which are not commonly used.
2011 Apr 21
0
C source code question (Robustbase edition)
Hi all,
I have been trying to add the  line: 
 h =  n - p0 + 1;
just after 
 h = n / 2 + 1;
(line 131) in the source code (the original paper mention this is possible
for p0<n).
with p0 declared as an int (actually i  used the same declaration 
protocol as n everywhere in the code).
The "new" source compiles, but when i give it reasonable 
values of p0, it runs unto
2017 Dec 03
1
Discourage the weights= option of lm with summarized data
Peter,
This is a highly structured text. Just for the discussion, I separate
the building blocks, where (D) and (E) and (F) are new:
BEGIN OF TEXT --------------------
(A)
Non-?NULL? ?weights? can be used to indicate that different
observations have different variances (with the values in ?weights?
being inversely proportional to the variances);
(B)
or equivalently, when the elements of
2012 Feb 29
2
Converting a function from Splus to R
I have a function written for Splus, when I run it in R I obtain get an error
because the function has the elements "0.d0" and "2.d0". How can I change it
to run in R?
The function can be found in page 230 from
 http://www.stat.wisc.edu/~mchung/teaching/stat471/stat_computing.pdf
Function is as follows:
gauher <- function(n) {# Gauss-Hermite: returns x,w so that
2007 Jul 10
3
ECDF, distribution of Pareto, distribution of Normal
Hello all,
I would like to plot the emperical CDF, normal CDF and pareto CDF in the
same graph and I amusing the following codes. "z" is a vector and I just
need the part when z between 1.6 and 3.
plot(ecdf(z), do.points=FALSE, verticals=TRUE,
xlim=c(1.6,3),ylim=c(1-sum(z>1.6)/length(z), 1))
x <- seq(1.6, 3, 0.1)
lines(x,pgpd(x, 1.544,0.4373,-0.2398), col="red")
y
2006 Dec 04
0
How to calculate area between ECDF and CDF?
Hi all,
I'm working with data to which I'm fitting three-parameter weibull 
distributions (shape, scale & shift). The data are of low sample sizes 
(between 10 and 80 observations), so I'm reluctant to check my fits 
using chi-square (also, I'd like to avoid bin choice issues). I'd use 
the Kolmogorov-Smirnov test, but of course this is invalid when the 
distribution
2008 Nov 08
2
lines, ecdf and colors
Hi.  I'm trying to plot two ecdf's on the same graph using two
different colors.  I can plot using the same color, but it doesn't
work when I change colors?  Any suggestions?  Thanks in advance for
your help.
x <- c(0.80, 0.83, 1.89, 1.04, 1.45, 1.38, 1.91, 1.64, 0.73, 1.46)
y <- c(1.15, 0.88, 0.90, 0.74, 1.21)
plot(ecdf(x))
# it works without col='blue', but doesn't
2006 Oct 21
2
problem with mode of marginal distriubtion of rdirichlet{gtools}
Hi all,
I have a problem using rdirichlet{gtools}.
For Dir( a1, a2, ..., a_n), its mode can be found at  $( a_i -1)/ (
\sum_{i}a_i - n)$;
The means are   $a_i / (\sum_{i} a_i ) $;
I tried to study the above properties using rdirichlet from gtools. The code
are:
##############
library(gtools)
alpha = c(1,3,9)  #totoal=13
mean.expect = c(1/13, 3/13,  9/13)
mode.expect = c(0,    2/10,  8/10) #
2008 Jul 15
1
Supressing printing from a function: ecdf
Dear R Users,
I am trying to suppress the information printed by the ecdf function 
during an assignment. Various alternatives have failed me so far:
> a=summary(ecdf(rnorm(100)))["1st Qu."]
Empirical CDF:    100 unique values with summary
> invisible(a=summary(ecdf(rnorm(100)))["1st Qu."])
Empirical CDF:    100 unique values with summary
> (function()
2010 Feb 18
0
2 ecdf from different set of data
Hi r-users,
 
I have 2 sets of data and I would like to superimpose this cumulative density in one graph.
 
I know how to put the 2 graphs in one same graph but my problem is the data are different.
 
> z[1:20]
 [1]  2.02347388  3.19514379  0.05188875  1.41333812  3.50249892  4.34272676  6.65639581  5.01533819  4.18207505
[10]  2.87615551  2.28202152  0.49431541  0.06570579  5.68352438
2007 Jun 09
1
What ECDF function?
Hello!
I want to plot a P-P plot. So I've implemented this function:
ppplot <- function(x,dist,...)
{
  pdf <- get(paste("p",dist,sep=""),mode="function");
  x <- sort(x);
  plot( pdf(x,...),  ecdf(x)(x));
}
I have two questions:
1. Is it right to draw as reference line the following:
    xx <- pdf(x,...);
    yy <- ecdf(x)(x);
    l <- lm(