[R] How does the r-distribution function work

2007-07-06 Thread pieter claassen
I am trying to understand what rbinom function does.

Here is some sample code. Are both the invocations of bfunc effectively
doing the same or I am missing the point?

Thanks,
Pieter

bfunc - function(n1,p1,sims) {
c-rbinom(sims,n1,p1)
c
}

a=c()
b=c()
p1=.5
for (i in 1:1){
a[i]=bfunc(30,p1,1)
}
b=bfunc(30,p1,1)

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Re: [R] How does the r-distribution function work

2007-07-06 Thread Peter Dalgaard
pieter claassen wrote:
 I am trying to understand what rbinom function does.

 Here is some sample code. Are both the invocations of bfunc effectively
 doing the same or I am missing the point?

   
There are some newbie issues with your code (you are extending a on 
every iteration, and your bfunc is just rbinom with the parameters in a 
different order), but basically, yes: They are conceptually the same. 
Both give 1 independent binomial samples.

In fact, if you reset the random number generator in between, they also 
give the same results (this is an implementation issue and not obviously 
guaranteed for any distribution) . Here's an example with smaller values 
than 1 and 30.

  set.seed(123)
  rbinom(10,1,.5)
 [1] 0 1 0 1 1 0 1 1 1 0

  set.seed(123)
  for (i in 1:10) print(rbinom(1,1,.5))
[1] 0
[1] 1
[1] 0
[1] 1
[1] 1
[1] 0
[1] 1
[1] 1
[1] 1
[1] 0

  set.seed(123)
  replicate(10, rbinom(1,1,.5))
 [1] 0 1 0 1 1 0 1 1 1 0


 Thanks,
 Pieter

 bfunc - function(n1,p1,sims) {
 c-rbinom(sims,n1,p1)
 c
 }

 a=c()
 b=c()
 p1=.5
 for (i in 1:1){
 a[i]=bfunc(30,p1,1)
 }
 b=bfunc(30,p1,1)

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Re: [R] How does the r-distribution function work

2007-07-06 Thread matthew5555

Hi, I have a problem. how can I solve a problem without t.test

for example:
x-c(1,2,3,4,5,6)
y-c(7,8,9)
t.test(x,y,alternative=less,paired=FALSE,var.equal=TRUE,con.level=0.95)

sorry for my english :)
-- 
View this message in context: 
http://www.nabble.com/How-does-the-r-distribution-function-work-tf4034026.html#a11460431
Sent from the R help mailing list archive at Nabble.com.

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[R] distribution graph

2007-06-12 Thread Wentzel-Larsen, Tore
The following gives two functions for producing distribution graphs:

distribution-graph

produces a single graph, and

multiple.distribution.graph

produces a number of graphs side by side.

Regards,
Tore Wentzel-Larsen
statistician
Centre for Clinical research
Armauer Hansen house 
Haukeland University Hospital
N-5021 Bergen
tlf   +47 55 97 55 39 (a)
faks  +47 55 97 60 88 (a)
email [EMAIL PROTECTED] 


Documentation:

distribution.graph

Description

distribution.graph produces a distribution graph of the data values. 

Usage

distribution.graph(xx, grouping=FALSE,
ngroups=10, xplace=c(0,1,.5),  halfband=.25,
xlab='', ylab='', pch=16,
lines=FALSE, lty='solid')

Arguments

xx  numeric, a vector of values for which to produce the 
distribution graph. Missing values are allowed, and are 
disregarded.

groupinglogical, if FALSE (the default) the actual values are graphed,
if TRUE the values are grouped before being plotted.

ngroups the number of groups (default 10) if grouping=TRUE.

xplace  vector with three components. The first two components define
the horizontal plotting range. The last component defines the
horizontal placement of the centre of the distribution graph.

halfbandHalf-length of the maximal horizontal band in the distribution
Graph, from the centre outwards. The bands should be within the 
Horizontal plotting range.

xlab, 
ylabx and y axis labels, as in plot.default.

pch plotting symbol, default 16 (solid circle).

lines   logical, if FALSE (the default) only points are plotted, if
TRUE the points are connected by lines.

lty line type, as in plot.default.


Value

A frequency table for the values actually plotted.

Examples

# a simple distribution graph with no grouping:
distribution.graph(floor(runif(100, 200, 310)))

# a similar graph with vertical bars only:
distribution.graph(floor(runif(100, 200, 310)), lines=TRUE, pch='')

# a distribution graph with grouping (points or line bars):
distribution.graph(runif(1000 ,0, 3), grouping=TRUE)
distribution.graph(runif(1000, 0, 3), grouping=TRUE, lines=TRUE, pch='')

# a distribution graph with grouping, 5 groups:
distribution.graph(runif(1000, 0, 10), grouping=TRUE, ngroups=5)
distribution.graph(rbinom(1000, 20, .7), grouping=TRUE, ngroups=5)


- - - - - - - - - - - - - - -

multiple.distribution.graph

Description

multiple.distribution.graph produces a number of distribution graphs of the 
data values, side by side. 

Usage

multiple.distribution.graph(xx, grouping=FALSE,
ngroups=10, xleft=0, xright=1, xmiddle=.5, xband=.5,
xlab=c(1:length(xx)), ylab='', pch=16,
lines=FALSE, lty='solid')
Arguments

xx  list of numeric variables, a vector of values for which to 
produce the distribution graph. Missing values are allowed, and are 
disregarded.

groupinglogical, if FALSE (the default) the actual values are graphed,
if TRUE the values are grouped before being plotted.

ngroups the number of groups (default 10) if grouping=TRUE.

xleft
xright
xmiddle xleft and xright define the horizontal plotting range within
each distribution graph. xmiddle defines the horizontal 
placement of the centre of each distribution graph.

xband   the part actually used for plotting, of the horizontal range
allocated top each individual graph.

xlab, 
ylabx and y axis labels, as in plot.default.

pch plotting symbol, default 16 (solid circle).

lines   logical, if FALSE (the default) only points are plotted, if
TRUE the points are connected by lines.

lty line type, as in plot.default.


Value

A list of frequency tables for the values actually plotted.


Examples

par(ask=TRUE)
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9))),
grouping=TRUE)
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9))),
grouping=TRUE,ngroups=3)
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9))),
grouping=TRUE,ngroups=3,lines=TRUE)
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9))),
grouping=TRUE,ngroups=3,lines=TRUE,pch='')
multiple.distribution.graph(as.list(data.frame(matrix(runif(72),ncol=9))),
grouping=TRUE,ngroups=5,lines=TRUE,pch='')
par(ask=FALSE)

# a more complicated list of numeric vectors:
xx - as.list(as.list(data.frame(matrix(runif(72,10,45),ncol=9
xx[[1]][c(1,3,4,8)]- NA
xx[[2]][c(2,4)]- NA
xx[[4]][c(3)]- NA
xx[[6]][c(2,5,8)]- NA
xx[[8]][c(1,2,8)]- NA
xx - lapply(xx,stripmiss)
xx[[1]][c(3)]- NA
xx[[3]][c(1,3,4,5)]- NA
xx[[4]][c(2,3)]- NA
xx[[8]][c(3,4)]- NA


[R] distribution of peaks in random data results

2007-05-31 Thread João Fadista
Dear all,
 
 I have the positions of N points spread through some sequence of length L 
(LN), and I would like to know how can do the following:
 
1- Permute the positions of the N points along the whole sequence. 
Assuming a uniform distribution I did:  position1 - runif(N, 1, L)
 
2- Apply a kernel convolution method to the resulting permuted points profile. 
For this I applied the function:  d - density(position1, bw = sj)
 
3- Record the heights of all peaks.
For this I used the estimated density values from the output of the density 
function above: heights1 -  d$y
 
4- Repeat step 1 and 2 to be able to have a distribution of the peaks from the 
random data results.
I don´t know how to perform this step!!!
 
5- Compute the threshold by determining the alfa-level in the empirical CDF of 
the null distribution.
Assuming ´heightsALL´ is the output of step 4 I would do this:  
plot(ecdf(heightsALL)). But I don´t know how to compute the threshold

6- Apply this threshold to the peaks estimate of the real peaks data, resulting 
in a series of significant peaks.
This step can be done by seeing the peaks in the real data that are above the 
threshold and classify these as significant at the alfa-level. 
 
The steps mentioned above are better illustrated with a picture that can be 
fetched here:
http://www.yousendit.com/transfer.php?action=downloadufid=0E3724F26CA53367


Best regards and thanks in advance,

João Fadista
Ph.d. student



 UNIVERSITY OF AARHUS   
Faculty of Agricultural Sciences
Dept. of Genetics and Biotechnology 
Blichers Allé 20, P.O. BOX 50   
DK-8830 Tjele   

Phone:   +45 8999 1900  
Direct:  +45 8999 1900  
E-mail:  [EMAIL PROTECTED] mailto:[EMAIL PROTECTED]   
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News and news media http://www.agrsci.org/navigation/nyheder_og_presse .

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[R] distribution graph

2007-03-23 Thread Plessen, Christian von

I am looking for a way to produce a distribution graph as in the example: 

(http://cecsweb.dartmouth.edu/release1.1/datatools/dgraph.php?year=2003geotype=STD_HRRevent=A01_DISeventtype=UTIL

Anybody who can help?

Christian von Plessen
Department of Pulmonary Medicine
Haukeland university hospital 
Bergen
Norway

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Re: [R] distribution graph

2007-03-23 Thread Michael Kubovy
?violinplot (You need to install the UsingR package first.)

On Mar 23, 2007, at 4:06 AM, Plessen, Christian von wrote:

 I am looking for a way to produce a distribution graph as in the  
 example:

 (http://cecsweb.dartmouth.edu/release1.1/datatools/dgraph.php? 
 year=2003geotype=STD_HRRevent=A01_DISeventtype=UTIL

 Anybody who can help?

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Re: [R] distribution graph

2007-03-23 Thread Ted Harding
On 23-Mar-07 11:06:49, Plessen, Christian von wrote:
 
 I am looking for a way to produce a distribution graph as in the
 example: 
 
 (http://cecsweb.dartmouth.edu/release1.1/datatools/dgraph.php?year=2003;
 geotype=STD_HRRevent=A01_DISeventtype=UTIL
 
 Anybody who can help?
 
 Christian von Plessen
 Department of Pulmonary Medicine
 Haukeland university hospital 
 Bergen
 Norway

The following (which anyway needs refinement, and can very
probably be done better) provides a basis (illustrated using
a sample from a log-normal distribution):


X-exp(rnorm(200,sd=0.25)+2)/5

H-hist(X,breaks=20)
C-H$counts
Y-H$mids
C1-C/2

C0-(-C1[1]-1/2):(C[1]-1/2); n0-length(C0)
plot(C0,rep(Y[1],n0),xlim=c(-max(C)/2,max(C)/2),ylim=c(min(Y),max(Y)))

for(i in (2:length(Y))){
  C0-(-C1[i]-1/2):(C1[i]-1/2); n0-length(C0)
  points(C0,rep(Y[i],n0))
}


Hoping this helps!
Ted.


E-Mail: (Ted Harding) [EMAIL PROTECTED]
Fax-to-email: +44 (0)870 094 0861
Date: 23-Mar-07   Time: 13:04:51
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Re: [R] distribution graph

2007-03-23 Thread Marc Schwartz
On Fri, 2007-03-23 at 14:22 +, [EMAIL PROTECTED] wrote:
 [Apologies -- there were errors in the code I posted previously.
  A corrected version is below]
 
 On 23-Mar-07 11:06:49, Plessen, Christian von wrote:
  
  I am looking for a way to produce a distribution graph as in the
  example: 
  
  (http://cecsweb.dartmouth.edu/release1.1/datatools/dgraph.php?year=2003;
  geotype=STD_HRRevent=A01_DISeventtype=UTIL
  
  Anybody who can help?
  
 
 The following (which anyway needs refinement, and can very
 probably be done better) provides a basis (illustrated using
 a sample from a log-normal distribution):
 
 
 X-exp(rnorm(200,sd=0.25)+2)/5
 
 H-hist(X,breaks=20)
 C-H$counts
 Y-H$mids
 C1-C/2
 
 C0-(-(C1[1]-1/2)):(C1[1]-1/2); n0-length(C0)
 plot(C0,rep(Y[1],n0),xlim=c(-max(C)/2,max(C)/2),ylim=c(min(Y),max(Y)))
 
 for(i in (2:length(Y))){
   if(C[i]==0) next
   C0 - (-(C1[i] - 1/2)):(C1[i] - 1/2); n0-length(C0)
   points(C0,rep(Y[i],n0))
 }
 
 
 Hoping this helps!
 Ted.


How about something like this:


DistPlot - function(x, digits = 1, ...)
{
  x - round(x, digits)
  
  Tab - table(x)

  Vals - sapply(Tab, function(x) seq(x) - mean(seq(x)))

  X.Vals - unlist(Vals, use.names = FALSE)
  tmp - sapply(Vals, length)
  Y.Vals - rep(names(tmp), tmp)

  plot(X.Vals, Y.Vals, ...)
}


Vec - exp(rnorm(200, sd = 0.25) + 2) / 5

DistPlot(Vec, pch = 19)



HTH,

Marc Schwartz

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Re: [R] distribution graph

2007-03-23 Thread Ted Harding
On 23-Mar-07 16:55:40, Marc Schwartz wrote:
 [...]
 How about something like this:
 
 
 DistPlot - function(x, digits = 1, ...)
 {
   x - round(x, digits)
   
   Tab - table(x)
 
   Vals - sapply(Tab, function(x) seq(x) - mean(seq(x)))
 
   X.Vals - unlist(Vals, use.names = FALSE)
   tmp - sapply(Vals, length)
   Y.Vals - rep(names(tmp), tmp)
 
   plot(X.Vals, Y.Vals, ...)
 }
 
 
 Vec - exp(rnorm(200, sd = 0.25) + 2) / 5
 
 DistPlot(Vec, pch = 19)

Very pretty, Marc -- and magic code!!

Ted.


E-Mail: (Ted Harding) [EMAIL PROTECTED]
Fax-to-email: +44 (0)870 094 0861
Date: 23-Mar-07   Time: 19:20:04
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[R] distribution overlap - how to quantify?

2007-01-25 Thread Doktor, Daniel
Dear R-Users,
 
my objective is to measure the overlap/divergence of two probability
density functions, p1(x) and p2(x). One could apply the chi-square test
or determine the potential mixture components and then compare the
respective means and sigmas. But I was rather looking for a simple
measure of similarity.
Therefore, I used the concept of 'intrinsic discrepancy' which is
defined as: 
 
\delta{p_{1},p_{2}} = min
 \left\{ \int_{\chi}p_{1}(x)\log \frac{p_{1}(x)}{p_{2}(x)}dx,
\int_{\chi}p_{2}(x)\log\frac{p_{2}(x)}{p_{1}(x)}dx \right\}

The smaller the delta the more similar are the distributions (0 when
identical). I implemented this in 'R' using an adaptation of the
Kullback-Leibler divergence. The function works, I get the expected
results.
 
The question is how to interpret the results. Obviously a delta of 0.5
reflects more similarity than a delta of 2.5. But how much more? Is
there some kind of a statistical test for such an index (other than a
simulation based evaluation)?
 
Thanks in advance,
 
Daniel
 
 
 
Daniel Doktor
PhD Student
Imperial College
Royal School of Mines Building, DEST, RRAG
Prince Consort Road
London SW7 2BP, UK
tel: 0044-(0)20-7589-5111-59276(ext)
 

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Re: [R] distribution of daily rainfall values in binned categories

2006-06-28 Thread Martin Maechler
 FJZ == Francisco J Zagmutt [EMAIL PROTECTED]
 on Wed, 28 Jun 2006 03:51:31 + writes:

FJZ Hi Etienne,
FJZ Somebody asked a somehow related question recently.  
FJZ http://tolstoy.newcastle.edu.au/R/help/06/06/29485.html

FJZ Take a look at cut? table? and barplot?
FJZ i.e.

  # Creates fake data from uniform(0,30)
  set.seed(1) ## - added by MM
  x=runif(50, 0,30)

  # Creates categories
  rain=cut(x,breaks=c( 0, 1,2.5,5, 10, 20, Inf))

  # Creates contingency table of categories
  tab=table(rain)

  # Plots frequencies of rainfall
  barplot(tab)


No, no, no!  Do not confuse histograms with bar plots!

-  barplot() is {one possibility} for visualizing discrete
   (categorical, factor) data,
-  hist() is for visualizing *continuous* data  (*)

As Jim Porzak replied, do use hist(): the example really is a matter
of visualization of a continuous distribution which should *not*
be done by a barplot.  Instead, e.g.,

  hist(x, breaks = c(0, 1,2.5,5, 10,20, max(pretty(max(x,
   freq = TRUE, col = gray)

will give a graphic similar to the above --- BUT also 
warns you about the hidden deception (aka sillyness) of *both* graphics:
Namely, the above hist() call warns you with

 Warning message:
 the AREAS in the plot are wrong -- rather use freq=FALSE in: 

and finally,

  hist(x, breaks = c(0, 1,2.5,5, 10,20, max(pretty(max(x, col=gray)

gives you a more honest graphic --- which -- for the runif()
example -- may finally lead to you to realize that using unequal
break may really not be such a good idea.
Note however that for the OP rainfall data, that may well be different
and if I look at rainfall data, I find I would rather view

   hist(log10( rainfall ))
or then
   plot(density( log10( rainfall ) ))

Martin Maechler, ETH Zurich

(*) From statistical point of view, histograms just density estimators, 
and -- as known for a while -- have quite some drawbacks.
Hence they should nowadays often be replaced by
plot(density(.), ..)


 From: etienne [EMAIL PROTECTED]
 To: r-help@stat.math.ethz.ch
 Subject: [R] distribution of daily rainfall values in binned categories
 Date: Tue, 27 Jun 2006 11:28:59 -0700 (PDT)
 
 Hi,
 
 I'm a newbie in using R and I would like to have a few
 clues as to how I could compute and plot a
 distribution of daily rainfall intensity in different
 categories.  I have daily values (mm/day) for several
 years and I need to show the frequency of 0-1, 1-2.5,
 2.5-5, 5-10, 10-20, 20+ mm/day.  Can this be done
 easily?
 
 Thanks,
 Etienne
 
 __
 R-help@stat.math.ethz.ch mailing list
 https://stat.ethz.ch/mailman/listinfo/r-help
 PLEASE do read the posting guide! 
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FJZ __
FJZ R-help@stat.math.ethz.ch mailing list
FJZ https://stat.ethz.ch/mailman/listinfo/r-help
FJZ PLEASE do read the posting guide! 
http://www.R-project.org/posting-guide.html

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Re: [R] distribution of daily rainfall values in binned categories

2006-06-28 Thread Francisco J. Zagmutt
Hi Martin

I agree with all your previous concerns.  I was just answering her question 
about visualizing frequencies for a continuous variable that is artificially 
categorized.  However, she did mention the word *distribution* (a part that 
I obviously ignored when I posted my answer) so your comments are more than 
appropriate. I am surprised nobody else jumped with the usual discussion 
about violin plots and his friends   ;-)

Cheers

Francisco



Dr. Francisco J. Zagmutt
College of Veterinary Medicine and Biomedical Sciences
Colorado State University




From: Martin Maechler [EMAIL PROTECTED]
Reply-To: Martin Maechler [EMAIL PROTECTED]
To: Francisco J. Zagmutt [EMAIL PROTECTED]
CC: [EMAIL PROTECTED], r-help@stat.math.ethz.ch
Subject: Re: [R] distribution of daily rainfall values in binned categories
Date: Wed, 28 Jun 2006 10:39:58 +0200

  FJZ == Francisco J Zagmutt [EMAIL PROTECTED]
  on Wed, 28 Jun 2006 03:51:31 + writes:

 FJZ Hi Etienne,
 FJZ Somebody asked a somehow related question recently.
 FJZ http://tolstoy.newcastle.edu.au/R/help/06/06/29485.html

 FJZ Take a look at cut? table? and barplot?
 FJZ i.e.

   # Creates fake data from uniform(0,30)
   set.seed(1) ## - added by MM
   x=runif(50, 0,30)

   # Creates categories
   rain=cut(x,breaks=c( 0, 1,2.5,5, 10, 20, Inf))

   # Creates contingency table of categories
   tab=table(rain)

   # Plots frequencies of rainfall
   barplot(tab)


No, no, no!  Do not confuse histograms with bar plots!

-  barplot() is {one possibility} for visualizing discrete
(categorical, factor) data,
-  hist() is for visualizing *continuous* data  (*)

As Jim Porzak replied, do use hist(): the example really is a matter
of visualization of a continuous distribution which should *not*
be done by a barplot.  Instead, e.g.,

   hist(x, breaks = c(0, 1,2.5,5, 10,20, max(pretty(max(x,
freq = TRUE, col = gray)

will give a graphic similar to the above --- BUT also
warns you about the hidden deception (aka sillyness) of *both* graphics:
Namely, the above hist() call warns you with

  Warning message:
  the AREAS in the plot are wrong -- rather use freq=FALSE in: 

and finally,

   hist(x, breaks = c(0, 1,2.5,5, 10,20, max(pretty(max(x, col=gray)

gives you a more honest graphic --- which -- for the runif()
example -- may finally lead to you to realize that using unequal
break may really not be such a good idea.
Note however that for the OP rainfall data, that may well be different
and if I look at rainfall data, I find I would rather view

hist(log10( rainfall ))
or then
plot(density( log10( rainfall ) ))

Martin Maechler, ETH Zurich

(*) From statistical point of view, histograms just density estimators,
 and -- as known for a while -- have quite some drawbacks.
 Hence they should nowadays often be replaced by
 plot(density(.), ..)


  From: etienne [EMAIL PROTECTED]
  To: r-help@stat.math.ethz.ch
  Subject: [R] distribution of daily rainfall values in binned 
categories
  Date: Tue, 27 Jun 2006 11:28:59 -0700 (PDT)
 
  Hi,
 
  I'm a newbie in using R and I would like to have a few
  clues as to how I could compute and plot a
  distribution of daily rainfall intensity in different
  categories.  I have daily values (mm/day) for several
  years and I need to show the frequency of 0-1, 1-2.5,
  2.5-5, 5-10, 10-20, 20+ mm/day.  Can this be done
  easily?
 
  Thanks,
  Etienne
 
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Re: [R] questions on local customized R distribution CD

2006-06-27 Thread Liaw, Andy
 
From: Duncan Murdoch
 
 On 6/26/2006 3:14 PM, Dongseok Choi wrote:
  Hello all!

I hope this is the right place to post this question.
   
The Oregon Chapter of ASA is working with local high 
 school teachers as one of its outreaching program.
We hope to use and test R as teaching tools.
So, we think that a menu system (like R commander) with a 
 few packages and a bit simplified installation instruction 
 need to be developed.
   
The main question is:
  1)
  Is it OK to develop a customized CD-ROM distribution of R  
 with pre-selected packages for high school? 
  It will be distributed free, of course.
  Also, we plan to make it available from the chap web or 
 deposit it to R-project, if requested.
 
 Generally the answer is yes, but read the GPL for the 
 conditions.  You do need to make the source code available.

I was under the impression that telling the user how to get the source code
would satisfy the GPL, instead of distributing the source along with the
binary.  Is that right?

  2)
If the customized distribution CD is OK, I also hope to 
 get some technical help/advice from the core group members if 
 any one is interested.
 
 See the R Installation and Administration manual first.  It 
 tells how to build R installers with non-standard included 
 packages.  Hopefully for 2.4.0 more customizations will be possible.

Yes, it's not all that hard.  Follow the directions carefully and literally
and there shouldn't be problem.

Andy

 
 Duncan Murdoch
 
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Re: [R] questions on local customized R distribution CD

2006-06-27 Thread Prof Brian Ripley
On Tue, 27 Jun 2006, Liaw, Andy wrote:

 From: Duncan Murdoch

 On 6/26/2006 3:14 PM, Dongseok Choi wrote:
 Hello all!

   I hope this is the right place to post this question.

   The Oregon Chapter of ASA is working with local high
 school teachers as one of its outreaching program.
   We hope to use and test R as teaching tools.
   So, we think that a menu system (like R commander) with a
 few packages and a bit simplified installation instruction
 need to be developed.

   The main question is:
 1)
 Is it OK to develop a customized CD-ROM distribution of R
 with pre-selected packages for high school?
 It will be distributed free, of course.
 Also, we plan to make it available from the chap web or
 deposit it to R-project, if requested.

 Generally the answer is yes, but read the GPL for the
 conditions.  You do need to make the source code available.

 I was under the impression that telling the user how to get the source code
 would satisfy the GPL, instead of distributing the source along with the
 binary.  Is that right?

No, the first part is definitely wrong.  (However, you don't have to 
distribute 'the source along with the binary', unless it is on the 
Internet.)

The obligation is on the distributor to make the exact sources available, 
not to rely on anyone else (e.g. CRAN, who might just lose them or not be 
available 2.99 years from now).  The relevant clauses are

 b) Accompany it with a written offer, valid for at least three
 years, to give any third party, for a charge no more than your
 cost of physically performing source distribution, a complete
 machine-readable copy of the corresponding source code, to be
 distributed under the terms of Sections 1 and 2 above on a medium
 customarily used for software interchange; or,

[The following clause c) does not apply if you repackage the 
distribution.]

If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent
access to copy the source code from the same place counts as
distribution of the source code, even though third parties are not
compelled to copy the source along with the object code.

See e.g.

http://www.gnu.org/licenses/gpl-faq.html#DistributeWithSourceOnInternet
http://www.gnu.org/licenses/gpl-faq.html#SourceAndBinaryOnDifferentSites

The easiest way to meet the obligations is to put the sources on the CD, 
especially as the sources concerned are only around 5% of the capacity of 
the CD.

-- 
Brian D. Ripley,  [EMAIL PROTECTED]
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel:  +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UKFax:  +44 1865 272595

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Re: [R] questions on local customized R distribution CD

2006-06-27 Thread Duncan Murdoch
On 6/27/2006 8:05 AM, Liaw, Andy wrote:
  
 From: Duncan Murdoch
 
 On 6/26/2006 3:14 PM, Dongseok Choi wrote:
  Hello all!

I hope this is the right place to post this question.
   
The Oregon Chapter of ASA is working with local high 
 school teachers as one of its outreaching program.
We hope to use and test R as teaching tools.
So, we think that a menu system (like R commander) with a 
 few packages and a bit simplified installation instruction 
 need to be developed.
   
The main question is:
  1)
  Is it OK to develop a customized CD-ROM distribution of R  
 with pre-selected packages for high school? 
  It will be distributed free, of course.
  Also, we plan to make it available from the chap web or 
 deposit it to R-project, if requested.
 
 Generally the answer is yes, but read the GPL for the 
 conditions.  You do need to make the source code available.
 
 I was under the impression that telling the user how to get the source code
 would satisfy the GPL, instead of distributing the source along with the
 binary.  Is that right?

Possibly, but not necessarily.  See section 3 of the GPL, distributed in 
the COPYING file with R.

Duncan Murdoch

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[R] distribution of daily rainfall values in binned categories

2006-06-27 Thread etienne
Hi,

I'm a newbie in using R and I would like to have a few
clues as to how I could compute and plot a
distribution of daily rainfall intensity in different
categories.  I have daily values (mm/day) for several
years and I need to show the frequency of 0-1, 1-2.5,
2.5-5, 5-10, 10-20, 20+ mm/day.  Can this be done
easily?

Thanks,
Etienne

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Re: [R] distribution of daily rainfall values in binned categories

2006-06-27 Thread Jim Porzak
?hist

 read about breaks

On 6/27/06, etienne [EMAIL PROTECTED] wrote:

 Hi,

 I'm a newbie in using R and I would like to have a few
 clues as to how I could compute and plot a
 distribution of daily rainfall intensity in different
 categories.  I have daily values (mm/day) for several
 years and I need to show the frequency of 0-1, 1-2.5,
 2.5-5, 5-10, 10-20, 20+ mm/day.  Can this be done
 easily?

 Thanks,
 Etienne

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-- 
HTH,
Jim Porzak
Loyalty Matrix Inc.
San Francisco, CA

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Re: [R] distribution of daily rainfall values in binned categories

2006-06-27 Thread Francisco J. Zagmutt
Hi Etienne,

Somebody asked a somehow related question recently.  
http://tolstoy.newcastle.edu.au/R/help/06/06/29485.html

Take a look at cut? table? and barplot?
i.e.
#Creates fake data from uniform(0,30)

x=runif(50, 0,30)

#Creates categories
rain=cut(x,breaks=c( 0, 1,2.5,5, 10, 20, Inf))

#Creates contingency table of categories
tab=table(rain)

#Plots frequencies of rainfall
barplot(tab)


I hope this helps!

Francisco

Dr. Francisco J. Zagmutt
College of Veterinary Medicine and Biomedical Sciences
Colorado State University




From: etienne [EMAIL PROTECTED]
To: r-help@stat.math.ethz.ch
Subject: [R] distribution of daily rainfall values in binned categories
Date: Tue, 27 Jun 2006 11:28:59 -0700 (PDT)

Hi,

I'm a newbie in using R and I would like to have a few
clues as to how I could compute and plot a
distribution of daily rainfall intensity in different
categories.  I have daily values (mm/day) for several
years and I need to show the frequency of 0-1, 1-2.5,
2.5-5, 5-10, 10-20, 20+ mm/day.  Can this be done
easily?

Thanks,
Etienne

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[R] questions on local customized R distribution CD

2006-06-26 Thread Dongseok Choi
Hello all!
  
  I hope this is the right place to post this question.
 
  The Oregon Chapter of ASA is working with local high school teachers as one 
of its outreaching program.
  We hope to use and test R as teaching tools.
  So, we think that a menu system (like R commander) with a few packages and a 
bit simplified installation instruction need to be developed.
 
  The main question is:
1)
Is it OK to develop a customized CD-ROM distribution of R  with pre-selected 
packages for high school? 
It will be distributed free, of course.
Also, we plan to make it available from the chap web or deposit it to 
R-project, if requested.
 
2)
  If the customized distribution CD is OK, I also hope to get some technical 
help/advice from the core group members if any one is interested.
 
 
Thank you very much in advance,
Dongseok Choi, PhD
The President of the Oregon Chapter of the ASA
 
 


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Re: [R] questions on local customized R distribution CD

2006-06-26 Thread Duncan Murdoch
On 6/26/2006 3:14 PM, Dongseok Choi wrote:
 Hello all!
   
   I hope this is the right place to post this question.
  
   The Oregon Chapter of ASA is working with local high school teachers as one 
 of its outreaching program.
   We hope to use and test R as teaching tools.
   So, we think that a menu system (like R commander) with a few packages and 
 a bit simplified installation instruction need to be developed.
  
   The main question is:
 1)
 Is it OK to develop a customized CD-ROM distribution of R  with pre-selected 
 packages for high school? 
 It will be distributed free, of course.
 Also, we plan to make it available from the chap web or deposit it to 
 R-project, if requested.

Generally the answer is yes, but read the GPL for the conditions.  You 
do need to make the source code available.
  
 2)
   If the customized distribution CD is OK, I also hope to get some technical 
 help/advice from the core group members if any one is interested.

See the R Installation and Administration manual first.  It tells how to 
build R installers with non-standard included packages.  Hopefully for 
2.4.0 more customizations will be possible.

Duncan Murdoch

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[R] Distribution Fitting

2006-05-26 Thread Lorenzo Isella
Hi,
I know this is a bit off-topic, but I am quite puzzled. I am going
through several papers about aerosol physics and in this field you
often have determine the parameters of a distribution to match your
experimental data (one typically uses a Gaussian mixture).
However, in many cases people plot a normalized empirical distribution
function and then perform some least-square fitting rather than using
likelihood functions.
As an undergrad, I was told that the former approach is correct only
if you have a model for the dynamics (e.g. Ohm law and you perform a
least-square fitting), but not if you deal with a distribution and you
pick random draws from it (in that case, one should maximize the
probability of drawing the data which were actually observed and this
leads to likelihood functions).
The two approaches do not seem equivalent to me, but I cannot believe
that this distinction is ignored in practice...
Many thanks

Lorenzo

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[R] Distribution Identification/Significance testing

2006-05-23 Thread Sachin J
Hi,
   
  What are methods for identifying the right distribution for the dataset? As 
far as I know Fisher test (p  alpha) for stat. significance or min(square 
error) are two criteria for deciding. What are the other alternatives? - 
CONFIDENCE INTERVAL?. If any, how can I accomplish them in R. 
   
  Thanx in advance.
   
  Sachin


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Re: [R] distribution of the product of two correlated normal

2006-04-25 Thread Peter Ruckdeschel
Yu, Xuesong schrieb:

 Many thanks to Peter for your quick and detailed response to my question.  
 I tried to run your codes, but seems like u is not defined for functions fp 
 and fm. what is u?
 I believe t=X1*X2
 
 nen0 - m2+c0*u ## for all u's used in integrate: never positive

no, this is not the problem; u is the local integration variable
in local functions f, fm, fp over which integrate() performs
integration;

it is rather the eps = eps default value passed in functions
f, fm, fp  which causes a recursive default value reference - problem;
change it as follows:

###
#code by P. Ruckdeschel, [EMAIL PROTECTED], rev. 04-25-06
###
#
#pdf of X1X2, X1~N(m1,s1^2), X2~N(m2,s2^2), corr(X1,X2)=rho, evaluated at t
#
#   eps is a very small number to catch errors in division by 0
###
#
dnnorm - function(t, m1, m2, s1, s2, rho,  eps = .Machine$double.eps ^ 0.5){
a - s1*sqrt(1-rho^2)
b - s1*rho
c - s2
### new:
f - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps0 = eps)
 # new (04-25-06): eps0 instead of eps as local variable to f
 {
  nen0 - m2+c0*u
  #catch a division by 0
  nen - ifelse(abs(nen0)eps0, nen0, ifelse(nen00, nen0+eps0, nen0-eps0))
  dnorm(u)/a0/nen * dnorm( t/a0/nen -(m1+b0*u)/a0)
 }
-integrate(f, -Inf, -m2/c, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value+
 integrate(f, -m2/c,  Inf, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value
}

###
#
#cdf of X1X2, X1~N(m1,s1^2), X2~N(m2,s2^2), corr(X1,X2)=rho, evaluated at t
#
#   eps is a very small number to catch errors in division by 0
###
#
pnnorm - function(t, m1, m2, s1, s2, rho,  eps = .Machine$double.eps ^ 0.5){
a - s1*sqrt(1-rho^2)
b - s1*rho
c - s2
### new:
fp - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps0 = eps)
 # new (04-25-06): eps0 instead of eps as local variable to fp
 {nen0 - m2+c0*u ## for all u's used in integrate: never negative
  #catch a division by 0
  nen  - ifelse(nen0eps0, nen0, nen0+eps0)
  dnorm(u) * pnorm( t/a0/nen- (m1+b0*u)/a0)
 }
### new:
fm - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps0 = eps)
 # new (04-25-06): eps0 instead of eps as local variable to fm
 {nen0 - m2+c0*u ## for all u's used in integrate: never positive
  #catch a division by 0
  nen  - ifelse(nen0 (-eps0), nen0, nen0-eps0)
  dnorm(u) * pnorm(-t/a0/nen+ (m1+b0*u)/a0)
 }
integrate(fm, -Inf, -m2/c, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value+
integrate(fp, -m2/c,  Inf, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value
}

##
For me this gives, e.g.:

 pnnorm(0.5,m1=2,m2=3,s1=2,s2=1.4,rho=0.8)
[1] 0.1891655
 dnnorm(0.5,m1=2,m2=3,s1=2,s2=1.4,rho=0.8)
[1] 0.07805282


Hth, Peter

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Re: [R] distribution of the product of two correlated normal

2006-04-24 Thread Peter Ruckdeschel
Yu, Xuesong writes:
 
 Does anyone know what the distribution for the product of two correlated
 normal? Say I have X~N(a, \sigma1^2) and Y~N(b, \sigma2^2), and the
 \rou(X,Y) is not equal to 0, I want to know the pdf or cdf of XY. Thanks
 a lot in advance.
 

There is no closed-form expression (at least not to my knowledge) ---
but you could easily write some code for a numerical evaluation of the pdf / 
cdf:

###
#code by P. Ruckdeschel, [EMAIL PROTECTED] 04-24-06
###
#
#pdf of X1X2, X1~N(m1,s1^2), X2~N(m2,s2^2), corr(X1,X2)=rho, evaluated at t
#
#   eps is a very small number to catch errors in division by 0
###
#
dnnorm - function(t, m1, m2, s1, s2, rho,  eps = .Machine$double.eps ^ 0.5){
a - s1*sqrt(1-rho^2)
b - s1*rho
c - s2
f - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps = eps)
 {
  nen0 - m2+c0*u
  #catch a division by 0
  nen - ifelse(abs(nen0)eps, nen0, ifelse(nen00, nen0+eps, nen0-eps))
  dnorm(u)/a0/nen * dnorm( t/a0/nen -(m1+b0*u)/a0)
 }
-integrate(f, -Inf, -m2/c, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value+
 integrate(f, -m2/c,  Inf, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value
}

###
#
#cdf of X1X2, X1~N(m1,s1^2), X2~N(m2,s2^2), corr(X1,X2)=rho, evaluated at t
#
#   eps is a very small number to catch errors in division by 0
###
#
pnnorm - function(t, m1, m2, s1, s2, rho,  eps = .Machine$double.eps ^ 0.5){
a - s1*sqrt(1-rho^2)
b - s1*rho
c - s2
fp - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps = eps)
 {nen0 - m2+c0*u ## for all u's used in integrate: never negative
  #catch a division by 0
  nen  - ifelse(nen0eps, nen0, nen0+eps)
  dnorm(u) * pnorm( t/a0/nen- (m1+b0*u)/a0)
 }
fm - function(u, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = c,  eps = eps)
 {
  nen0 - m2+c0*u ## for all u's used in integrate: never positive
  #catch a division by 0
  nen  - ifelse(nen0 -eps, nen0, nen0-eps)
  dnorm(u) * pnorm(-t/a0/nen+ (m1+b0*u)/a0)
 }
integrate(fm, -Inf, -m2/c, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value+
integrate(fp, -m2/c,  Inf, t = t, m1 = m1, m2 = m2, a0 = a, b0 = b, c0 = 
c)$value
}
##

If you have to evalute dnnorm() or pnnorm() at a lot of values of t
for some given m1, m2, s1, s2, rho, then you should first evaluate
[p,d]nnorm() on a (smaller) number of gridpoints of values for t first
and then use something like approxfun() or splinefun() to give you a
much faster evaluable function.

Hth, Peter

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[R] distribution of the product of two correlated normal

2006-04-23 Thread Yu, Xuesong
Hi,

 

Does anyone know what the distribution for the product of two correlated
normal? Say I have X~N(a, \sigma1^2) and Y~N(b, \sigma2^2), and the
\rou(X,Y) is not equal to 0, I want to know the pdf or cdf of XY. Thanks
a lot in advance.

 

yu


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[R] distribution maps

2006-01-06 Thread Rogério Rosa da Silva
Dears,

I would like to know if there is a R package(s) on CRAN that can
generate distribution maps  of species.

I think that this issue not has been discussed, but I did not  search
extensively on CRAN or help archives.

Best regards

Rogério

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Re: [R] distribution maps

2006-01-06 Thread Roger Bivand
On Fri, 6 Jan 2006, Rogério Rosa da Silva wrote:

 Dears,
 
 I would like to know if there is a R package(s) on CRAN that can
 generate distribution maps  of species.
 
 I think that this issue not has been discussed, but I did not  search
 extensively on CRAN or help archives.

Could I suggest the Spatial and Environmetrics Task Views reached from 
the Task View item in the navigation bar on CRAN? You may also find the 
R-sig-geo mailing list a useful place to make your question a little more 
detailed - you do not say anything about your data, and a helpful reply 
would depend on knowing that.

 
 Best regards
 
 Rogério
 

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: [EMAIL PROTECTED]

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Re: [R] Distribution fitting problem

2005-11-08 Thread Bernardo Rangel Tura
At 10:32 2/11/2005, you wrote:

I am using the MASS library function

fitdistr(x, dpois, list(lambda=2))

but I get

Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
 Function cannot be evaluated at initial parameters
In addition: There were 50 or more warnings (use warnings() to see the first
50)

and all the first 50 warnings say

1:  non-integer x = 1.45
etc

Can anyone tell me what I am doing wrong. p.s. the data was read in from
a .csv file that I wrote using octave

Mark,

Try fitdistr(x, Poisson)

I think this is enough for fit Poisson distribuition for your data


Bernardo Rangel Tura, MD, MSc
National Institute of Cardiology Laranjeiras
Rio de Janeiro Brazil 


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[R] Distribution fitting problem

2005-11-02 Thread Mark Miller
I am using the MASS library function 

fitdistr(x, dpois, list(lambda=2))

but I get 

Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
Function cannot be evaluated at initial parameters
In addition: There were 50 or more warnings (use warnings() to see the first 
50)

and all the first 50 warnings say 

1:  non-integer x = 1.45
etc

Can anyone tell me what I am doing wrong. p.s. the data was read in from 
a .csv file that I wrote using octave

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Re: [R] Distribution fitting problem

2005-11-02 Thread Dieter Menne
Mark Miller mmiller at nassp.uct.ac.za writes:

 
 I am using the MASS library function 
 
 fitdistr(x, dpois, list(lambda=2))
 
 but I get 
 
 Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
 Function cannot be evaluated at initial parameters
 In addition: There were 50 or more warnings (use warnings() to see the first 
 50)
 

The docs say:

For the following named distributions, reasonable starting values will be 
computed if start is omitted or only partially specified: cauchy, gamma, 
logistic, negative binomial (parametrized by mu and size), t and weibull. 

dpois is not among them, so you probably have to provide reasonable starting 
values for the parameters.

Dieter

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Re: [R] Distribution fitting problem

2005-11-02 Thread Mark Miller
Can you advise another distribution, was thinking of exponential, but was 
advised poisson since independent, forgot about requiring integers


On Wednesday 02 November 2005 14:44, you wrote:
 Mark Miller wrote:
  I am using the MASS library function
 
  fitdistr(x, dpois, list(lambda=2))
 
  but I get
 
  Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
  Function cannot be evaluated at initial parameters
  In addition: There were 50 or more warnings (use warnings() to see the
  first 50)
 
  and all the first 50 warnings say
 
  1:  non-integer x = 1.45
  etc
 
  Can anyone tell me what I am doing wrong. p.s. the data was read in from
  a .csv file that I wrote using octave

 Hi, Mark,

 If you think the data are poisson, the observations should be integers.

 --sundar

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Re: [R] Distribution fitting problem

2005-11-02 Thread Adelchi Azzalini
On Wed, 2 Nov 2005 14:32:52 +0200, Mark Miller wrote:

MM I am using the MASS library function 
MM 
MM fitdistr(x, dpois, list(lambda=2))
MM 
MM but I get 
MM 
MM Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
MM Function cannot be evaluated at initial parameters
MM In addition: There were 50 or more warnings (use warnings() to see
MM the first  50)
MM 
MM and all the first 50 warnings say 
MM 
MM 1:  non-integer x = 1.45
MM etc
MM 

are the data integers (as implicit in the assumption of Poisson dist'n)?
the above message seems to say that they are not 

Adelchi Azzalini

-- 
Adelchi Azzalini  [EMAIL PROTECTED]
Dipart.Scienze Statistiche, Università di Padova, Italia
tel. +39 049 8274147,  http://azzalini.stat.unipd.it/

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Re: [R] Distribution fitting problem

2005-11-02 Thread Sundar Dorai-Raj
Hi, Mark,

Not without seeing you data. You only provide the first value is a 
warning message below.

--sundar

Mark Miller wrote:
 Can you advise another distribution, was thinking of exponential, but was 
 advised poisson since independent, forgot about requiring integers
 
 
 On Wednesday 02 November 2005 14:44, you wrote:
 
Mark Miller wrote:

I am using the MASS library function

fitdistr(x, dpois, list(lambda=2))

but I get

Error in optim(start, mylogfn, x = x, hessian = TRUE, ...) :
Function cannot be evaluated at initial parameters
In addition: There were 50 or more warnings (use warnings() to see the
first 50)

and all the first 50 warnings say

1:  non-integer x = 1.45
etc

Can anyone tell me what I am doing wrong. p.s. the data was read in from
a .csv file that I wrote using octave

Hi, Mark,

If you think the data are poisson, the observations should be integers.

--sundar

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Re: [R] Distribution

2005-02-21 Thread Sean Davis
Srini
You should probably look at ?hist.  If you look at the value section, you 
will see that you can get the information you want from the values returned 
from hist.  If these are microarray probes and intensities, there may be 
specific methods for visualizing the data available from the bioconductor 
project (www.bioconductor.org).

Hope this helps,
Sean
- Original Message - 
From: Srinivas Iyyer [EMAIL PROTECTED]
To: Rhelp r-help@stat.math.ethz.ch
Sent: Monday, February 21, 2005 6:21 PM
Subject: [R] Distribution


Dear group,
apologies for asking a simple question. I have a file
where the data looks like this:
ProbeIntensity
0:0 501.0
1:0 17760.5
2:0 511.0
3:0 18468.3
4:0 199.8
5:0 508.0
6:0 17241.8
7:0 507.5
8:0 17910.0
9:0 482.5
10:0 17480.3
11:0 434.0
12:0 17631.3
13:0 444.8
14:0 17423.0
15:0 505.3
16:0 16693.0
17:0 438.5
18:0 16920.0
19:0 491.3
20:0 16878.0
21:0 486.3
22:0 16582.0
23:0 483.8
24:0 16694.8
25:0 452.3
26:0 16221.5
27:0 438.3
28:0 17119.8
29:0 455.5
30:0 16579.0
31:0 424.5
32:0 16691.3
33:0 472.0
My question is how do I know the distribution of the
intensities. My aim is to find out the number of
intensities or probes that fall in a certain range.
For example 500 probes has intensities ranging from 50
to 150.
300 probes has intensities ranging from 151-250
I have no clue how to do it for 500,000 probes. Can
any one please help doing it in R.
thanks and apologies again
srini
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Re: [R] Distribution

2005-02-21 Thread Spencer Graves
 Have you considered qqnorm or hist?  If yes, PLEASE do read 
the posting guide! http://www.R-project.org/posting-guide.html;.  It 
might help you phrase your question so you are more likely to get a 
useful response -- and it might help you get the answer for yourself 
without waiting for someone to reply. 

 hope this helps.  spencer graves
Srinivas Iyyer wrote:
Dear group, 
apologies for asking a simple question. I have a file
where the data looks like this:
ProbeIntensity
0:0	501.0
1:0	17760.5
2:0	511.0
3:0	18468.3
4:0	199.8
5:0	508.0
6:0	17241.8
7:0	507.5
8:0	17910.0
9:0	482.5
10:0	17480.3
11:0	434.0
12:0	17631.3
13:0	444.8
14:0	17423.0
15:0	505.3
16:0	16693.0
17:0	438.5
18:0	16920.0
19:0	491.3
20:0	16878.0
21:0	486.3
22:0	16582.0
23:0	483.8
24:0	16694.8
25:0	452.3
26:0	16221.5
27:0	438.3
28:0	17119.8
29:0	455.5
30:0	16579.0
31:0	424.5
32:0	16691.3
33:0	472.0

My question is how do I know the distribution of the
intensities. My aim is to find out the number of
intensities or probes that fall in a certain range. 

For example 500 probes has intensities ranging from 50
to 150.
300 probes has intensities ranging from 151-250
I have no clue how to do it for 500,000 probes. Can
any one please help doing it in R.
thanks and apologies again
srini
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RE: [R] Distribution

2005-02-21 Thread Liaw, Andy
You can use table(cut(intensity, breaks)), where `intensity' is the vector
of intensity values, and `breaks' are the boundaries of the bins (e.g., c(0,
150, 250,  ...)).

Andy

 From: Srinivas Iyyer
 
 Dear group, 
 apologies for asking a simple question. I have a file
 where the data looks like this:
 ProbeIntensity
 0:0   501.0
 1:0   17760.5
 2:0   511.0
 3:0   18468.3
 4:0   199.8
 5:0   508.0
 6:0   17241.8
 7:0   507.5
 8:0   17910.0
 9:0   482.5
 10:0  17480.3
 11:0  434.0
 12:0  17631.3
 13:0  444.8
 14:0  17423.0
 15:0  505.3
 16:0  16693.0
 17:0  438.5
 18:0  16920.0
 19:0  491.3
 20:0  16878.0
 21:0  486.3
 22:0  16582.0
 23:0  483.8
 24:0  16694.8
 25:0  452.3
 26:0  16221.5
 27:0  438.3
 28:0  17119.8
 29:0  455.5
 30:0  16579.0
 31:0  424.5
 32:0  16691.3
 33:0  472.0
 
 
 My question is how do I know the distribution of the
 intensities. My aim is to find out the number of
 intensities or probes that fall in a certain range. 
 
 For example 500 probes has intensities ranging from 50
 to 150.
 
 300 probes has intensities ranging from 151-250
 
 I have no clue how to do it for 500,000 probes. Can
 any one please help doing it in R.
 
 thanks and apologies again
 
 srini
 
 __
 R-help@stat.math.ethz.ch mailing list
 https://stat.ethz.ch/mailman/listinfo/r-help
 PLEASE do read the posting guide! 
 http://www.R-project.org/posting-guide.html
 


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Re: [R] Distribution

2005-02-21 Thread Adaikalavan Ramasamy
You can read in the data using read.delim() or read.table(). For
illustration let us generate some artificial data and suppose that you
are interested in equal sized breaks of 5 (you can define your own break
points instead).

   x   - rchisq(50, df=10, ncp=5)
   brk - seq(0, 5*ceiling(max(x)/5), by=5) # increments of size 5
   h   - hist(x, breaks=brk, plot=FALSE)

h$breaks, h$counts will give you the count and break points but I always
have trouble matching which interval the counts belong to.


Another easier way is to use cut() followed by table() where the labels
of cut is helpful.

   table( cut( x, breaks=brk ) )

As a bonus, you can simplify specifying the break points by including
Infinite as the endpoint in cut.

   brk2 - seq(0, max(x), by=5) # increments of size 5
   table( cut( x, breaks=c(brk2, Inf) ) )


Regards, Adai


On Mon, 2005-02-21 at 18:44 -0500, Sean Davis wrote:
 Srini
 
 You should probably look at ?hist.  If you look at the value section, you 
 will see that you can get the information you want from the values returned 
 from hist.  If these are microarray probes and intensities, there may be 
 specific methods for visualizing the data available from the bioconductor 
 project (www.bioconductor.org).
 
 Hope this helps,
 Sean
 
 - Original Message - 
 From: Srinivas Iyyer [EMAIL PROTECTED]
 To: Rhelp r-help@stat.math.ethz.ch
 Sent: Monday, February 21, 2005 6:21 PM
 Subject: [R] Distribution
 
 
  Dear group,
  apologies for asking a simple question. I have a file
  where the data looks like this:
  ProbeIntensity
  0:0 501.0
  1:0 17760.5
  2:0 511.0
  3:0 18468.3
  4:0 199.8
  5:0 508.0
  6:0 17241.8
  7:0 507.5
  8:0 17910.0
  9:0 482.5
  10:0 17480.3
  11:0 434.0
  12:0 17631.3
  13:0 444.8
  14:0 17423.0
  15:0 505.3
  16:0 16693.0
  17:0 438.5
  18:0 16920.0
  19:0 491.3
  20:0 16878.0
  21:0 486.3
  22:0 16582.0
  23:0 483.8
  24:0 16694.8
  25:0 452.3
  26:0 16221.5
  27:0 438.3
  28:0 17119.8
  29:0 455.5
  30:0 16579.0
  31:0 424.5
  32:0 16691.3
  33:0 472.0
 
 
  My question is how do I know the distribution of the
  intensities. My aim is to find out the number of
  intensities or probes that fall in a certain range.
 
  For example 500 probes has intensities ranging from 50
  to 150.
 
  300 probes has intensities ranging from 151-250
 
  I have no clue how to do it for 500,000 probes. Can
  any one please help doing it in R.
 
  thanks and apologies again
 
  srini
 
  __
  R-help@stat.math.ethz.ch mailing list
  https://stat.ethz.ch/mailman/listinfo/r-help
  PLEASE do read the posting guide! 
  http://www.R-project.org/posting-guide.html
 
 
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 R-help@stat.math.ethz.ch mailing list
 https://stat.ethz.ch/mailman/listinfo/r-help
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Re: [R] Distribution of Data (was: your reference on this problem highly appreciated)

2004-07-11 Thread Spencer Graves
 There are many tools for this, e.g., qqnorm, density, and in 
library(MASS) fitdistr.  Also do a literature search on transformations 
(especially to transformations to normality) and on mixture 
distributions, esp. Titterington, Smith and Makov (1986) Statistical 
Analysis of Finite Mixture Distributions (Wiley). 

 What is the nature of your application?  If you tell us more about 
the context, many people could tell you which distributions might be 
plausible and which would not be credible except as an approximation, 
e.g., a normal distribution for numbers that can not be negative and 
whose distribution might be positively skewed. 

 hope this helps.  spencer graves
p.s.  PLEASE do read the posting guide! 
http://www.R-project.org/posting-guide.html 

Yong Wang wrote:
please help me on this
- Message Text -
Dear all R users
first, sorry for that this question might not be appropriate to ask here.
   
I wanna know theories or techinques aimed at following questions:
   
I have a sample, say,K(at the range from 0 to 2); the sample data's
central  moments m(1)---m(j) are estimated(j can be large).
also, I can use some methodology to calculate the upper and lower bound of
the probabilty of any interested interval, say, for the interval  
(400--800)
   
with all these information, I wanna recover the distribution of the data,
at least recover to some approximating  analytic form.Does anybady know
such theory or techiniques?
   
your help will be highly appreciated.
best regards
yong

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[R] distribution of second order statistic

2003-12-15 Thread Eugene Salinas (R)
Hi,

I am getting some weird results here and I think I am missing something. 
I am trying to program a function that for a set of random variables 
drawn from uniform distributions plots that distribution of the second 
order statistic of the ordered variables. (ie I have n uniform 
distributions on [0, w_i] for w_i different w_j and i=1..n. I want to 
plot the distribution of the second order statistic ie one less the 
maximum.

I thought that the way to do this is to calculate:
F=  Sum over i { (1-Fi) * Product of all j different i of Fj} + Product 
over all i of Fi

where Fi are just the respective uniform cdf for variable i.

The problem is that when I do this and plot F over the range from 0 to 
the highest of the w_i I don't get a cdf but something that slopes down 
at some point again. What is going on?

Any help is greately appreciated

Thanks, eugene.

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Re: [R] distribution of second order statistic

2003-12-15 Thread Prof Brian Ripley
The order statistics have a beta distribution, so pbeta is all you need.

On Mon, 15 Dec 2003, Eugene Salinas (R) wrote:

 I am getting some weird results here and I think I am missing something. 
 I am trying to program a function that for a set of random variables 
 drawn from uniform distributions plots that distribution of the second 
 order statistic of the ordered variables. (ie I have n uniform 
 distributions on [0, w_i] for w_i different w_j and i=1..n. I want to 
 plot the distribution of the second order statistic ie one less the 
 maximum.
 
 I thought that the way to do this is to calculate:
 F=  Sum over i { (1-Fi) * Product of all j different i of Fj} + Product 
 over all i of Fi
 
 where Fi are just the respective uniform cdf for variable i.
 
 The problem is that when I do this and plot F over the range from 0 to 
 the highest of the w_i I don't get a cdf but something that slopes down 
 at some point again. What is going on?

-- 
Brian D. Ripley,  [EMAIL PROTECTED]
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel:  +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UKFax:  +44 1865 272595

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[R] Distribution transformations

2003-11-23 Thread Viola Rossini
Dear R-Users,
I have a question that bothers me in the last few days. It is supposed to be easy but 
I can't come up with a solution. 
Are there any functions in R dealing with transforming empirical and parametric 
distributions? I have two data sets of observed variables that I want to transform to 
Frechet and Uniform distribution. 
I would appreciate if someone could inform me about R-functions for this purpose or 
enligthen me how to do it by myself.
Thank you very much in advance,
Viola Rossini




-

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Re: [R] Distribution transformations

2003-11-23 Thread Rolf Turner

You wrote:

 Dear R-Users,
 
 I have a question that bothers me in the last few days. It is
 supposed to be easy but I can't come up with a solution.  Are there
 any functions in R dealing with transforming empirical and parametric
 distributions? I have two data sets of observed variables that I want
 to transform to Frechet and Uniform distribution.  I would appreciate
 if someone could inform me about R-functions for this purpose or
 enligthen me how to do it by myself.
 
 Thank you very much in advance,
 Viola Rossini

Is this a homework question?

cheers,

Rolf Turner
[EMAIL PROTECTED]

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Re: [R] Distribution transformations

2003-11-23 Thread Spencer Graves
 For the uniform distribution, have you considered something like 
(((1:n)-0.5)/n))[order(x)]?  For the Frechet distribution, a search 
- R site search from www.r-project.org exposed something that 
should help.  The information you need seems to be there. 

 hope this helps.  spencer graves

Viola Rossini wrote:

Dear R-Users,
I have a question that bothers me in the last few days. It is supposed to be easy but I can't come up with a solution. 
Are there any functions in R dealing with transforming empirical and parametric distributions? I have two data sets of observed variables that I want to transform to Frechet and Uniform distribution. 
I would appreciate if someone could inform me about R-functions for this purpose or enligthen me how to do it by myself.
Thank you very much in advance,
Viola Rossini



-

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Re: [R] Distribution transformations

2003-11-23 Thread Viola Rossini
I am still not getting it. 
I am trying to understand multivariate distributions and copulas. In the beginning of 
each article it is said that the observed data must be transformed to uniform or 
frechet distribution by means of probability integral transform. Apparently this is 
something easy and trivial and a standard procedure in introductory statistics. Well, 
I have some books in statistics of different degrees of complexity but unfortunately I 
cannot find the answer there. All examples are only about how to generate a random 
sample with desired (always exponential) distribution.
Now, I have two variables X and Y and I want to transform them to Frechet or uniform. 
I was just thinking, if this is so simple and trivial as all stat books say, then, it 
must exist a simple function for it in R. 
 
 
P.s. @Rolf, I would like to have it as a homework but I am afraid I am too old for a 
school.

Rolf Turner [EMAIL PROTECTED] wrote:
You wrote:

 Dear R-Users,
 
 I have a question that bothers me in the last few days. It is
 supposed to be easy but I can't come up with a solution. Are there
 any functions in R dealing with transforming empirical and parametric
 distributions? I have two data sets of observed variables that I want
 to transform to Frechet and Uniform distribution. I would appreciate
 if someone could inform me about R-functions for this purpose or
 enligthen me how to do it by myself.
 
 Thank you very much in advance,
 Viola Rossini

Is this a homework question?

cheers,

Rolf Turner
[EMAIL PROTECTED]



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Re: [R] Distribution transformations

2003-11-23 Thread kjetil
On 23 Nov 2003 at 19:35, Viola Rossini wrote:

The frechet dirtribution is in the evd (extreme value dist) package 
on CRAN. 

The basic preinciple is that if U is uniform (0,1) anf F
is a cumulative distrubution function, then
F^{-1}(U) is distributed as F. 

Kjetil Halvorsen

 I am still not getting it. 
 I am trying to understand multivariate distributions and copulas. In
 the beginning of each article it is said that the observed data must
 be transformed to uniform or frechet distribution by means of
 probability integral transform. Apparently this is something easy and
 trivial and a standard procedure in introductory statistics. Well, I
 have some books in statistics of different degrees of complexity but
 unfortunately I cannot find the answer there. All examples are only
 about how to generate a random sample with desired (always
 exponential) distribution. Now, I have two variables X and Y and I
 want to transform them to Frechet or uniform. I was just thinking, if
 this is so simple and trivial as all stat books say, then, it must
 exist a simple function for it in R. 
 
 
 P.s. @Rolf, I would like to have it as a homework but I am afraid I am
 too old for a school.
 
 Rolf Turner [EMAIL PROTECTED] wrote:
 You wrote:
 
  Dear R-Users,
  
  I have a question that bothers me in the last few days. It is
  supposed to be easy but I can't come up with a solution. Are there
  any functions in R dealing with transforming empirical and
  parametric distributions? I have two data sets of observed variables
  that I want to transform to Frechet and Uniform distribution. I
  would appreciate if someone could inform me about R-functions for
  this purpose or enligthen me how to do it by myself.
  
  Thank you very much in advance,
  Viola Rossini
 
 Is this a homework question?
 
 cheers,
 
 Rolf Turner
 [EMAIL PROTECTED]
 
 
 
 -
 
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Re: [R] Distribution transformations

2003-11-23 Thread Peter Dalgaard
[EMAIL PROTECTED] writes:

 On 23 Nov 2003 at 19:35, Viola Rossini wrote:
 
 The frechet dirtribution is in the evd (extreme value dist) package 
 on CRAN. 
 
 The basic preinciple is that if U is uniform (0,1) anf F
 is a cumulative distrubution function, then
 F^{-1}(U) is distributed as F. 

[Slightly unfortunate double use of F there] 

...and conversely if X has distribution D with continuous cumulative
distribution function F, then F(X) will have a uniform distribution. I
suspect this was the clue that Viola was missing. This requires that
you know F, though. 

-- 
   O__   Peter Dalgaard Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics 2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark  Ph: (+45) 35327918
~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907

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