Re: [R] Win upgrade pb (virus)

2011-11-12 Thread Mario Valle

Thanks to all that responded privately!
If you have AVG and needs the colorspace (or ggplot2) package do the 
following from a suitably privileged account:


1) Open AVG gui and select Components-Anti virus from the menu
2) Click Advanced settings... and then go to Temporary disable AVG 
protection Here you need half a million clicks to disable protection 
for 10 min
3) Install colorspace package from R (I installed ggplot2 that installs 
colorspace)
4) Go to the user library and note the path to the colorspace.dll . In 
my case it is:
C:\Users\mvalle\R\win-library\2.14\colorspace\libs\i386\colorspace.dll 
(SHIFT-click and then Copy as path is handy)
5) In the open AVG window click Manage Exceptions then Add File and 
add the path above
6) On the main AVG gui there is a big button that reenables protection. 
Voilà, no more problems.


Thanks again!
mario

On 11-Nov-11 11:34, Mario Valle wrote:
I just upgraded my Win7 32bits installation to 2.14.0 after 
deinstalling 2.12.x
First thing I moved the win-library from 2.12 to 2.14 and executed a 
update.packages(ask='graphics',checkBuilt=TRUE)

(Swiss mirror).
This aborts with the console message:

Error in if (any(diff)) { : missing value where TRUE/FALSE needed

And the antivirus (AVG) pops up complaining that colorspace.dll 
contains the virus Win32/Heur
I cannot ignore the thread because update.packages has already crashed 
when I can reach the antivirus dialogbox to push the ignore button.

To continue I had to remove the colorspace and ggplot2 packages.

Is it a known problem? What else can I do (except removing the above 
packages or changing antivirus)?


Thanks!
mario



--
Ing. Mario Valle
Data Analysis and Visualization Group| http://www.cscs.ch/~mvalle
Swiss National Supercomputing Centre (CSCS)  | Tel:  +41 (91) 610.82.60
v. Cantonale Galleria 2, 6928 Manno, Switzerland | Fax:  +41 (91) 610.82.82

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Re: [R] Estimating IRT models by using nlme() function

2011-11-12 Thread Dimitris Rizopoulos
Note that there are several IRT dedicated packages in R, such as the ltm 
and eRm packages. For more info you may check the Psychometrics Task 
View at: http://cran.r-project.org/web/views/Psychometrics.html



I hope it helps.

Best,
Dimitris



On 11/11/2011 9:38 PM, Cengiz Zopluoğlu wrote:

Hi,

I have a question about estimating IRT models by using nlme, not just rasch
model, but also other models.

Behavior Research Methods
http://www.springerlink.com/content/1554-351x/  Volume
37, Number 2http://www.springerlink.com/content/1554-351x/37/2/, 202-218,
DOI: 10.3758/BF03192688
Using SAS PROC NLMIXED to fit item response theory models (2005). Ching-Fan
Sheuhttps://mail.google.com/mail/u/0/html/compose/static_files/goog_851944013,
Cheng-Te 
Chenhttps://mail.google.com/mail/u/0/html/compose/static_files/goog_851944013,
Ya-Hui Su and Wen-Chung Wang

An example of this is provided in the paper above. They use SAS PROC
NLMIXED, and estimate all possible binary and Polytomous IRT models. I want
to replicate what they did using R and nlme package. I am able to fit rasch
model, but have some error messages for 2PL IRT model. So, I could not go
beyond that.

This is really important for me, because any nonlinear model can be fitted
by using this approach. I would like to see how well nlme() package
recovers true parameters, not just regular IRT models but also some other
less used IRT models.

Here is the example. Let's say I have the following dataset. 1000 people
responds five items.


ID  Item Response d1 d2 d3 d4 d5

  1.1  110  1  0  0  0  0

  1.2  120  0  1  0  0  0

  1.3  130  0  0  1  0  0

  1.4  141  0  0  0  1  0

  1.5  150  0  0  0  0  1

  2.1  211  1  0  0  0  0

  2.2  220  0  1  0  0  0

  2.3  230  0  0  1  0  0

  2.4  241  0  0  0  1  0

  2.5  250  0  0  0  0  1

  3.1  310  1  0  0  0  0

  3.2  320  0  1  0  0  0

  3.3  331  0  0  1  0  0

  3.4  341  0  0  0  1  0

  3.5  350  0  0  0  0  1

  ..

  ..

1000.1 100011  1  0  0  0  0

1000.2 100020  0  1  0  0  0

1000.3 100031  0  0  1  0  0

1000.4 100041  0  0  0  1  0

1000.5 100050  0  0  0  0  1

The items are nested within students. Response is the actual dependent
variable. d1, d2, d3, d4, and d5 are the corresponding dummy codes for each
item. We treat persons as random effects, and item parameters as fixed
effects. To fit Rasch model, I run the following code:


   d- read.table(data.txt, header=TRUE)
d1- d$d1
d2- d$d2
d3- d$d3
d4- d$d4
d5- d$d5
  ###
onePL- function(b1,b2,b3,b4,b5,theta) { #nonlinear model to fit
 b= b1*d1+b2*d2+b3*d3+b4*d4+b5*d5
 exp((theta-b))/(1+exp((theta-b)))
}
#
nlme(model=Response ~ onePL(b1,b2,b3,b4,b5,theta),
data = d,
fixed = b1+b2+b3+b4+b5 ~ 1,
random = theta ~ 1 | ID,
start=c(b1=0,b2=0,b3=0,b4=0,b5=0),
)

   *OUTPUT *

  Nonlinear mixed-effects model fit by maximum likelihood
   Model: Response ~ onePL(b1, b2, b3, b4, b5, theta)
   Data: d
   Log-likelihood: -2597.344
   Fixed: b1 + b2 + b3 + b4 + b5 ~ 1
 b1 b2 b3 b4 b5
  -1.1240371  1.5931634  0.2574785 -2.0993236  0.8881437
  Random effects:
  Formula: theta ~ 1 | ID
 theta  Residual
  StdDev: 0.9765999 0.3780802
  Number of Observations: 5000
  Number of Groups: 1000


This make sense to me. Actually, the data was simulated data, and the b
parameters were close to true values used to generate data. Also the
standard deviation of random effects (theta or latent ability level in this
case) was close to 1 that was used to generate IRT person ability
parameters.

Then, I run the following code to estimate 2 PL IRT model. It was all same,
just add an additional a parameter for each item.


   twoPL- function(a1,a2,a3,a4,a5,b1,b2,b3,b4,b5,theta) {
 a= a1*d1+a2*d2+a3*d3+a4*d4+a5*d5
 b= b1*d1+b2*d2+b3*d3+b4*d4+b5*d5
 exp(a*(theta-b))/(1+exp(a*(theta-b)))
}
  nlme(model=Response ~ twoPL(a1,a2,a3,a4,a5,b1,b2,b3,b4,b5,theta),
data = d,
fixed = a1+a2+a3+a4+a5+b1+b2+b3+b4+b5 ~ 1,
random = theta ~ 1 | ID,
start=c(a1=1,a2=1,a3=1,a4=1,a5=1,b1=0,b2=0,b3=0,b4=0,b5=0),
)


It gives the following error:

*Error in MEEM(object, conLin, control$niterEM) :
   Singularity in backsolve at level 0, block 1*

Is there anyone who have an idea what I am doing wrong? Is there any error
in the syntax? I never used nlme package before, so I might be missing some
components in the code. Or, is this just estimation problem and nlme() can
not fit this model for some reason?

I would appreciate any help.

Thanks




Re: [R] Help

2011-11-12 Thread Patrick Burns

You've been told how to do what you ask.
But I'm not convinced that you really
want to do what you asked.

It might be better to do whatever you
want with the data leaving it all in one
object.  There are many ways of doing that,
the 'by' function is one of them.

On 11/11/2011 20:24, Francesca wrote:

Dear Contributors
I would like to perform this operation using a loop, instead of repeating
the same operation many times.
The numbers from 1 to 4 related to different groups that are in the
database and for which I have the same data.


 x-c(1,3,7)

datiP1- datiP[datiP$city ==1,x];

datiP2- datiP[datiP$city ==2,x];

datiP3- datiP[datiP$city ==3,x]

datiP4- datiP[datiP$city ==4,x];


--
Patrick Burns
pbu...@pburns.seanet.com
twitter: @portfolioprobe
http://www.portfolioprobe.com/blog
http://www.burns-stat.com
(home of 'Some hints for the R beginner'
and 'The R Inferno')

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Re: [R] Estimating IRT models by using nlme() function

2011-11-12 Thread Cengiz Zopluoğlu
Thanks for your suggestion, Dimitris.

I know (and use) all of these R packages for IRT (I am actually writer of
one of them, EstCRM). I also use specialized commercial software such as
BILOG and MULTILOG.

My goal is to be able to estimate IRT model parameters in a nonlinear mixed
effects regression framework. Recently, there has been some efforts to do
that as I give one reference in m previous e-mail. There are two advantages
of using non-linear mixed effects regression for IRT estimation. One of
them is that it gives a kind of unified approach, because it is very
flexible. You can change the nonlinear model however you like, and try to
estimate very different models. Then, see which one fits your data better.
So, you don't have to force yourself to fit regular and well know IRT
models if you have reasons to fit another model. Second, it allows you to
model higher clusters. Most of the time, we collect data from clusters, and
the subjects within a cluster are not independent from each other. It's a
well known concept in HLM framework, and measured by intra-class
correlation coefficient. I have never seen in IRT literature about this
issue, and we really don't know how cluster dependencies might affect IRT
parameter estimation. So, nonlinear mixed effects regression approach might
allow you to model a third (or may be a fourth) cluster above the students,
and take the cluster dependencies into account while estimating IRT
parameters. It also provides flexibilities for other IRT applications (
such as detecting DIF items).

Anyway, my goal is not basically estimating IRT parameters. I can do it in
so many different ways by using other softwares. My goal is to do it in a
nonlinear mixed effects regression framework, and see how well it does
comparing to the traditional estimation methods. I think ICC component is
very important and its possible impacts were never adressed in IRT
literature for parameter estimation. This is open to investigation. But, I
need to figure out this nlme() thing first. I can use SAS, because people
already provided all SAS syntax to estimate IRT parameters for all
well-known models in nonlinear mized effect approach. But, I want to see it
if nlme() can replicate what they did since I am an R fan.







2011/11/12 Dimitris Rizopoulos d.rizopou...@erasmusmc.nl

 Note that there are several IRT dedicated packages in R, such as the ltm
 and eRm packages. For more info you may check the Psychometrics Task View
 at: 
 http://cran.r-project.org/web/**views/Psychometrics.htmlhttp://cran.r-project.org/web/views/Psychometrics.html


 I hope it helps.

 Best,
 Dimitris




 On 11/11/2011 9:38 PM, Cengiz Zopluoğlu wrote:

 Hi,

 I have a question about estimating IRT models by using nlme, not just
 rasch
 model, but also other models.

 Behavior Research Methods
 http://www.springerlink.com/**content/1554-351x/http://www.springerlink.com/content/1554-351x/
  Volume
 37, Number 
 2http://www.springerlink.com/**content/1554-351x/37/2/http://www.springerlink.com/content/1554-351x/37/2/,
 202-218,

 DOI: 10.3758/BF03192688
 Using SAS PROC NLMIXED to fit item response theory models (2005).
 Ching-Fan
 Sheuhttps://mail.google.com/**mail/u/0/html/compose/static_**
 files/goog_851944013https://mail.google.com/mail/u/0/html/compose/static_files/goog_851944013
 ,
 Cheng-Te Chenhttps://mail.google.com/**mail/u/0/html/compose/static_**
 files/goog_851944013https://mail.google.com/mail/u/0/html/compose/static_files/goog_851944013
 ,
 Ya-Hui Su and Wen-Chung Wang

 An example of this is provided in the paper above. They use SAS PROC
 NLMIXED, and estimate all possible binary and Polytomous IRT models. I
 want
 to replicate what they did using R and nlme package. I am able to fit
 rasch
 model, but have some error messages for 2PL IRT model. So, I could not go
 beyond that.

 This is really important for me, because any nonlinear model can be fitted
 by using this approach. I would like to see how well nlme() package
 recovers true parameters, not just regular IRT models but also some other
 less used IRT models.

 Here is the example. Let's say I have the following dataset. 1000 people
 responds five items.


ID  Item Response d1 d2 d3 d4 d5

  1.1  110  1  0  0  0  0

  1.2  120  0  1  0  0  0

  1.3  130  0  0  1  0  0

  1.4  141  0  0  0  1  0

  1.5  150  0  0  0  0  1

  2.1  211  1  0  0  0  0

  2.2  220  0  1  0  0  0

  2.3  230  0  0  1  0  0

  2.4  241  0  0  0  1  0

  2.5  250  0  0  0  0  1

  3.1  310  1  0  0  0  0

  3.2  320  0  1  0  0  0

  3.3  331  0  0  1  0  0

  3.4  341  0  0  0  1  0

  3.5  350  0  0  0  0  1

  ..

  ..

 1000.1 100011  1  0  0  0  0

Re: [R] need help

2011-11-12 Thread S Ellison


Supreet kaur [ksupre...@gmail.com] 
 how do I calculate the reliability between the two groups
 using the ICCs?

Looking for the irr (inter-rater reliability package) might help; as the name 
suggests, it includes a variety of measures of rater reliability.

S Ellison

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This email and any attachments are confidential. Any use...{{dropped:8}}

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[R] plotting a bivariate quadratic curve

2011-11-12 Thread Yackov Lubarsky
Hi,

I would like to plot a x,y curve described by the equation :

Ax^2 + Bx + Cy^2 + Dy + E == 0

(A,B,C,D,E are constants)

This sounds like quite the common task but haven't been able to figure
out how to do this. Could you please help ? I am new to R so probably
missing something basic.

Thanks

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[R] Second-order effect in Parametric Survival Analysis

2011-11-12 Thread ryusuke
Hi experts,

http://r.789695.n4.nabble.com/file/n4034318/Parametric_survival_analysis_2nd-order_efffect.JPG
Parametric_survival_analysis_2nd-order_efffect.JPG 
As we know a normal survival regression is the equation (1)
Well, I'ld like to modify it to be 2nd-order interaction model as shown in
equation(2)

Question:
Assume a and z is two covariates.
x = dummy variable (1 or 0)
z = factors (peoples' name)
fit - survreg(Surv(time,censor)~x*z, data=sample, dist=exponential)

I tried to apply survreg(), while I have few questions:
1) If */survreg(Surv(time,censor)~x*z, data=sample, dist=exponential)/*
correct?
2) If the baseline hazard is the value excluded both x and z effects?
3) How can I get the value and plot the hazard with only x effect (but
exclude effect z)

Thanks


Best,
Ryusuke


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[R] logistic Regression using lmer

2011-11-12 Thread arunkumar1111
Hi

can we perform logistic regression using lmer function. Please help me with
this

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[R] Please Help

2011-11-12 Thread avish kamdar

HiI want to construct a logliikelood function in RHere is the situationy=number 
of particles emitted in 1 hr period~pois(30)p=probability of detection of 
radiation particlesx=number of particles detected by a radiation 
detector~pois(30p)where p~beta(a,1)I have to calculate the loglikehood for a 
for the range a(2,50)I wish to simulate 100 random samples for each aHere is my 
code:-m=481n=100x = c(15, 36, 29, 28, 37, 32, 25, 27, 31, 21, 25, 27, 28, 31, 
28, 20, 34, 25, 20, 34, 15,21, 28, 24, 31, 19, 34, 29, 18, 25, 16, 19, 44, 26, 
34, 31, 21, 28, 11, 31, 21, 34, 25, 25,30, 23, 21, 35, 36, 21, 27, 29, 30, 22, 
25, 30, 24, 27, 28, 22, 36, 29, 33, 35, 30, 32, 27,26, 25, 27, 23, 21, 39, 33, 
24, 21, 19, 34, 32, 28, 27, 28, 23, 20, 24, 29, 21, 22, 31, 28,27, 28, 29, 21, 
30, 28, 31, 22, 29, 18)a=c(1:m)*0.1+1.9p-rbeta(n,a,1)loglik-numeric(m)for(i 
in 
1:n){p[i]-rbeta(n,a[i],1)x[i]-rpois(n,p[i]*30)loglik-function(x,p)logLik(a=a(i))-n*log(a)+(log(30)*sum(x))-sum(log(factorial(x)))-30*(!
 sum(p[i]))+sum(x[i]*log(p[i]))+(a[j]-1)*sum(log(p[i]))}But somehow I am not 
getting the answer please HELPP.S. the data for x is a random sample of number 
of particles detected in 1 hr (given in the question)Really appreciate the 
helpThanks


  
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Re: [R] Subsetting data leads to funky plots

2011-11-12 Thread Sarah Goslee
Hi,

On Sat, Nov 12, 2011 at 2:04 AM, Vinny Moriarty vwmoria...@gmail.com wrote:
 I'm trying out a basic plot, but something about the way I subset my data
 leads to problems with the plot.


 Here is the first bit of my data set

 year,date,location,quadrat_juvenile,photo_location,photo_exists,genus,count,divers
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Acanthastrea,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Acropora,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Astreopora,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Cyphastrea,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Favia,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Fungia,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Gardinoseris,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Herpolitha,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Leptastrea,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Leptoseris,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Lobophyllia,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Millepora,0,HP+MEM
 2005,2005-04-30, 1 Fringing Reef,1, 1 Fringing Reef Coral Transect Pole 1-2
 Quadrat 1,t,Montastrea,0,HP+MEM

dput() with a sample of your data would be useful, so that we ca try
it. Among other things, the example you give above doesn't *have* the
values that you're subsetting on, so we can't easily try your specific
code.

str() of your data would also be useful. Are these factors? Strings?

The small reproducible example is important.


 I need to breakdown the data before I can plot it, so this is the stepwise
 code I use:

 Juv=read.csv(juvenile_density_20110506.csv)
 Juv$count[Juv$count0]- NA #Missing data is imputed as negative data, so
 first label it as NA
 JuvFor=subset(Juv,(location== 2 Outer 10 m) | (location== 1 Outer 10
 m)) #Subset the data of interest
 Juv_Sum_by_quad=aggregate(count~year+location+quadrat_juvenile,data=
 JuvFor,sum) # Calculate sum of each quadrat
 Juv_Avg=aggregate(count~year+location,data=Juv_Sum_by_quad, mean)
 #Calculate yearly means

 So far so good.

Is it? Did you look at Juv_Avg to make sure that it contains what you expect?


 I thought I could do this:

 plot(Juv_Sum1$year, Juv_Sum1$count,type=L)


There's no type=L, although there is type=l

Is Juv_Sum1 sorted by year? Without a reproducible example, I can't
see which of the many things that could go wrong have gone wrong. R
does exactly what you tell it, and it sounds like you may have given
it data that weren't sorted.

For that matter, there's no Juv_Sum1 in the code you gave, so I don't
have the slightest idea what might be in it.

 But not only do I get odd separate lines as opposed to a time series line
 plot, but I the first tick mark on the x-axis lists the amount of rows in
 my data. I can fix it by saving the final object as a .csv and reloading it
 the data- but that defeats the whole purpose. Can anyone explain why I get
 this plot result?

 Looking through past posts I found that I can get away with just plotting
 the y-axis. And if I modify the x axis separately I can get the plot I'm
 looking for.

 plot(Juv_Sum1$count,xaxt=n)
 axis(1,at=1:length(Juv_Sum1$year),labels=Juv_Sum1$year)


 But I'm concerned about why my data subsets are giving me odd results in
 the first place, especially as I move on into more complicated bits of code.

This list is generally quite helpful, but not telepathic. See these
two lines from every message (below)? That's what we need.

 PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
 and provide commented, minimal, self-contained, reproducible code.


Sarah
-- 
Sarah Goslee
http://www.functionaldiversity.org

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[R] processing data of hierarchical river network

2011-11-12 Thread tlange
Hi,

I have some hydrochemical data from observation stations of a river
network. The data set provides information about the river hierarchy, i.e.
the order of the rivers (main river is 1st order, contributing is 2nd
order, and contributing to 2nd is 3rd order... etc).

Now I would like to use the hierarchical information to:
a) plot a dendrogram of the observation stations
b) perform some simple statistics on the different branches

What packages are needed to conduct that investigation?
How the hierarchical information should be formated to be easily processed
with R?

Thank you,
Torsten

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Re: [R] Please Help

2011-11-12 Thread David Winsemius

Two problems with your post:

a) you used a format that is not accepted by the mail server and  
resulted in all of your linefeeds being removed, so it is now  
basically unreadable. As the Posting Guide says, please use plain  
text. (And please read the Posting Guide for yourself ... and do it  
now before reading further.) All the free mailing services provide  
mechanisms for constructing plain text emails.


b) it appears to be homework, and homework submission are discouraged.  
You can attach a plea describing why you should be exempted from this  
rule, but it might require identifying your self more completely and  
explaining why you are not using the services of the educational  
institution you are studying under.



On Nov 12, 2011, at 8:09 AM, avish kamdar wrote:



HiI want to construct a logliikelood function in RHere is the  
situationy=number of particles emitted in 1 hr  
period~pois(30)p=probability of detection of radiation  
particlesx=number of particles detected by a radiation  
detector~pois(30p)where p~beta(a,1)I have to calculate the  
loglikehood for a for the range a(2,50)I wish to simulate 100 random  
samples for each aHere is my code:-m=481n=100x = c(15, 36, 29, 28,  
37, 32, 25, 27, 31, 21, 25, 27, 28, 31, 28, 20, 34, 25, 20, 34,  
15,21, 28, 24, 31, 19, 34, 29, 18, 25, 16, 19, 44, 26, 34, 31, 21,  
28, 11, 31, 21, 34, 25, 25,30, 23, 21, 35, 36, 21, 27, 29, 30, 22,  
25, 30, 24, 27, 28, 22, 36, 29, 33, 35, 30, 32, 27,26, 25, 27, 23,  
21, 39, 33, 24, 21, 19, 34, 32, 28, 27, 28, 23, 20, 24, 29, 21, 22,  
31, 28,27, 28, 29, 21, 30, 28, 31, 22, 29, 18)a=c(1:m)*0.1+1.9p- 
rbeta(n,a,1)loglik-numeric(m)for(i in 1:n){p[i]-rbeta(n,a[i], 
1)x[i]-rpois(n,p[i]*30)loglik-function(x,p)logLik(a=a(i))-n*log(a) 
+(log(30)*sum(x))-sum(log(factorial(x)))-30*(!
sum(p[i]))+sum(x[i]*log(p[i]))+(a[j]-1)*sum(log(p[i]))}But somehow I  
am not getting the answer please HELPP.S. the data for x is a random  
sample of number of particles detected in 1 hr (given in the  
question)Really appreciate the helpThanks




[[alternative HTML version deleted]]



David Winsemius, MD
West Hartford, CT

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[R] State space model

2011-11-12 Thread Kristian Lind
Hi,

I'm trying to estimate the parameters of a state space model of the
following form

measurement eq:

z_t = a + b*y_t + eps_t

transition eq

y_t+h = (I -exp(-hL))theta + exp(-hL)y_t+ eta_{t+h}.

The problem is that the distribution of the innovations of the transition
equation depend on the previous value of the state variable.
To be exact: y_t|y_{t-1} ~N(mu, Q_t) where Q is a diagonal matrix with
elements equal to

Q_{i,t} =
sigma_i*(1-exp(-kappa_i*h)/kappa_i*(theta_i/2*(1-exp(kappa_i*h)+exp(-kappa_i*h)y_{t-1,i}

The fkf returns the filtered states variables so y_{t-1,i} is available. I
just can't figure out how to write my program in such a way  that this
information is included and updated in the state space model for each
iteration in optim. Any suggestions on how to solve this are much
appreciated.

Thank you,

Kristian.

Below my program where the variance matrices are just identity matrices and
the data is just random numbers. I used the example from the FKF package as
framework.

library(FKF) #loading Fast Kalman Filter package
library(Matrix) # matrix exponential package
library(BB)
library(alabama)
x - matrix(abs(rnorm(400)), nrow=10, ncol=40)
m - 2 # m is the number of state variables
n - ncol(x) # is the length of the observed sample
d - nrow(x) # is the number of observed variables.
h - 1/52
## creating state space representation of 2-factor CIR model
CIR2ss - function(K_1, K_2, sigma_1, sigma_2, lambda_1, lambda_2, theta_1,
theta_2, delta_0, delta_1, delta_2)  {
  ## defining auxilary parameters,
phi_11 - sqrt((K_1+lambda_1)^2+2*sigma_1^2*delta_1)
  phi_21 - sqrt((K_2+lambda_2)^2+2*sigma_2^2*delta_2)
phi_12 - K_1+lambda_1+phi_11
phi_22 - K_2+lambda_2+phi_21
phi_13 - 2*K_1*theta_1/sigma_1^2
phi_23 - 2*K_2*theta_2/sigma_2^2
a - array(1, c(d,n))
phi_14 - numeric(d)
phi_24 - numeric(d)
b1 - numeric(d)
b2 - numeric(d)
for(t in 1:d){
phi_14[t] - 2*phi_11+phi_12*(exp(phi_11*t)-1)
phi_24[t] - 2*phi_21+phi_22*(exp(phi_21*t)-1)
a[t] - delta_0 - phi_13/(t)*log(2*phi_11*exp(phi_12*(t)/2)/phi_14[t])-
phi_23/(t)*log(2*phi_21*exp(phi_22*(t)/2)/phi_24[t])
b1[t] - (delta_1/(t))*2*(exp(phi_11*(t))-1)/phi_14[t]
b2[t] - (delta_2/(t))*2*(exp(phi_21*(t))-1)/phi_24[t]
}
b - array(c(b1,b2), c(d,m,n))
j - -matrix(c(K_1, 0, 0, K_2), c(2,2))*h
explh - as.matrix(expm(j))

Tt - array(explh, c(m,m,n)) #array giving the factor of the transition
equation
Zt - b #array giving the factor of the measurement equation
ct - a #matrix giving the intercept of the measurement equation
dt - as.matrix((diag(m)-explh)%*%c(theta_1, theta_2)) #matrix giving
the intercept of the transition equation
GGt - array(diag(d), c(d,d,1)) #array giving the variance of the
disturbances of the measurement equation
HHt - diag(m) #array giving the variance of the innovations of the
transition equation
a0 - c(0.5, 0.5) #vector giving the initial value/estimation of the
state variable
P0 - matrix(1e6, nrow = 2, ncol = 2) # matrix giving the variance of a0
return(list(a0 = a0, P0 = P0, ct = ct, dt = dt, Zt = Zt, Tt = Tt, GGt =
GGt,
HHt = HHt))
}
## Objective function passed to optim
objective - function(parm, yt) {
  sp - CIR2ss(parm[K_1], parm[K_2], parm[sigma_1], parm[sigma_2],
parm[lambda_1], parm[lambda_2],
   parm[theta_1], parm[theta_2], parm[delta_0],
parm[delta_1], parm[delta_2])

  ans - fkf(a0 = sp$a0, P0 = sp$P0, dt = sp$dt, ct = sp$ct, Tt = sp$Tt,
   Zt = sp$Zt, HHt = sp$HHt, GGt = sp$GGt, yt = yt)
  return(-ans$logLik)
}

parm - c(K_1 =  0.6048, K_2 = 0.656, sigma_1 =0.1855, sigma_2 =0.5524,
   lambda_1 =0.55, lambda_2 =0.009, theta_1 = 0.173, theta_2 = 0.12,
   delta_0 =0.686, delta_1 =-0.003, delta_2=0.0025)

hin - function(parm, yt){
  h- numeric(2)
  h[1] - 2*parm[1]*parm[7]-parm[3]^2
  h[2] - 2*parm[2]*parm[8]-parm[4]^2
  h
}
##optimizing objective function
fit - auglag(par = parm, fn = objective, yt = x, control.outer =
list(method = CG), hin = hin)
print(fit)

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Re: [R] logistic Regression using lmer

2011-11-12 Thread Ben Bolker
arunkumar akpbond007 at gmail.com writes:

 
 Hi
 
 can we perform logistic regression using lmer function. Please help me with
 this
 

  Yes.  
  
  library(lme4)
  glmer([reponse]~[fixed effects (covariates)]+(1|[grouping variable]),
data=[data frame], family=binomial)

  Further questions on this topic should probably go to the
r-sig-mixed-models mailing list.

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Re: [R] plotting a bivariate quadratic curve

2011-11-12 Thread Duncan Murdoch

On 11-11-12 5:50 AM, Yackov Lubarsky wrote:

Hi,

I would like to plot a x,y curve described by the equation :

Ax^2 + Bx + Cy^2 + Dy + E == 0

(A,B,C,D,E are constants)

This sounds like quite the common task but haven't been able to figure
out how to do this. Could you please help ? I am new to R so probably
missing something basic.



R is not very good at that, but one way to do it is to draw a contour 
plot of the bivariate function, with a single contour at level 0.  For 
example,


A - B - C - D - 1
E - -1
x - y - seq(-3, 3, len=100)
z - outer(x, y, function(x, y) A*x^2 + B*x + C*y^2 + D*y + E)
contour(x, y, z, levels=0, drawLabels=FALSE)

Another would be to solve for y as a function of x, and draw both 
branches.


Duncan Murdoch

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Re: [R] plotting a bivariate quadratic curve

2011-11-12 Thread Barry Rowlingson
On Sat, Nov 12, 2011 at 10:50 AM, Yackov Lubarsky yluba...@gmail.com wrote:
 Hi,

 I would like to plot a x,y curve described by the equation :

 Ax^2 + Bx + Cy^2 + Dy + E == 0

 (A,B,C,D,E are constants)

 This sounds like quite the common task but haven't been able to figure
 out how to do this. Could you please help ? I am new to R so probably
 missing something basic.

 What you may be missing was all figured out by the ancient Greeks and
they didnt even have R in their alphabet!

 You've got this:

http://mathworld.wolfram.com/QuadraticCurve.html

 but with b=0. I'm not sure how many of the awkward cases (line pairs,
imaginary everything) disappear with b=0, but you can compute the
Delta, I, J, and K determinants to figure it out. Then set theta to
seq(0,2*pi,len=100) and compute r from the polar equation form. Plot
r*cos(theta), r*sin(theta)...

Confession: its been a long time since I did maths like this (forgive
me father, for I have not sin'd).

Barry

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Re: [R] Passing parameters

2011-11-12 Thread ftonini
Hi Annie,

The error is in the R script...you start reading with Args[1] but instead
you should start with Args[5] etc. because (I believe) that R --slave
--vanilla --args count as
[1]   [2][3][4]

Therefore, Args[5] it's the first argument you use...try that and let me
know!!
I am trying something similar for one of my scripts

Francesco


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[R] With an example - Re: rbind.data.frame drops attributes for factor variables

2011-11-12 Thread Sammy Zee
When I use rbind() or rbind.data.frame() to add a row to an existing
dataframe, it appears that attributes for the column of type factor are
dropped. See the sample example below to reproduce the problem. Please
suggest How I can fix this.

Thanks,
Sammy

a=c(Male, Male, Female, Male)
b=c(1,2,3,4)
c=c(great, bad, good, bad)
dataset- data.frame (gender = a, count = b, answer = c)

 dataset

 gender count answer
1   Male 1  great
2   Male 2bad
3 Female 3   good
4   Male 4bad


 attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

Now adding some custom attributes to column dataset$answer

attributes(dataset$answer)-c(attributes(dataset$answer),list(newattr1=custom-attr1))
attributes(dataset$answer)-c(attributes(dataset$answer),list(newattr2=custom-attr2))

 attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

$newattr1
[1] custom-attr1

$newattr2
[1] custom-attr2

However as soon as I add a row to this data frame (dataset) by rbind(),
it loses the custom
attributes (newattr1 and newattr2) I have just added

newrow = c(gender=Female, count = 5, answer = great)

dataset - rbind(dataset, newrow)

 attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

the two custom attributes are dropped!! Any suggestion why this is
happening.

On Fri, Nov 11, 2011 at 11:44 AM, Jeff Newmiller
jdnew...@dcn.davis.ca.uswrote:

 As the doctor says, if it hurts don't do that.

 A factor is a sequence of integers with a corresponding list of character
 strings. Factors in two separate vectors can and usually do map the same
 integer to different strings, and R cannot tell how you want that resolved.

 Convert these columns to character before combining them, and only convert
 to factor when you have all of your possibilities present (or you specify
 them in the creation of the factor vector).
 ---
 Jeff NewmillerThe .   .  Go Live...
 DCN:jdnew...@dcn.davis.ca.usBasics: ##.#.   ##.#.  Live
 Go...
  Live:   OO#.. Dead: OO#..  Playing
 Research Engineer (Solar/BatteriesO.O#.   #.O#.  with
 /Software/Embedded Controllers)   .OO#.   .OO#.  rocks...1k
 ---
 Sent from my phone. Please excuse my brevity.

 Sammy Zee szee2...@gmail.com wrote:

 Hi all,
 
 When I use rbind() or rbind.data.frame() to add a row to an existing
 dataframe, it appears that attributes for the column of type factor
 are
 dropped. I see the following post with same problem. However i did not
 see
 any reply to the following posting offering a solution. Could someone
 please help.
 
 
 http://r.789695.n4.nabble.com/rbind-data-frame-drops-attributes-for-factor-variables-td919575.html
 
 Thanks,
 Sammy
 
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[R] changelog for MASS?

2011-11-12 Thread Xu Wang
Does anyone know where I can find a changelog for MASS?

It's difficult to know whether I should ask my company to update the package
or not. We are usually required to show the changelog, but I can't find one.

Thank you,

Xu

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Re: [R] R v2.13.2 - Cannot find Rcmd on path?

2011-11-12 Thread jack306
Dear all:


I could not able to find rcmd using the following path: either R version
(2.13.2 or 2.14.0); either rtools version (2.13 or 2.14). My os is winxp. 
The variables set in path are as follows.

c:\Rtools\bin;c:\Rtools\MinGW\bin;C:\Perl\bin; C:\Perl\site\bin;
c:\Rtools\bin; C:\Program Files\R\R-2.13.2\bin\i386; C:\Program Files\MiKTeX
2.9\miktex\bin;%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program
Files\Common Files\Roxio Shared\DLLShared\;C:\Program Files\Common
Files\Roxio Shared\10.0\DLLShared\;c:\Program Files\Microsoft SQL
Server\90\Tools\binn\

After I tried setpath.bat file, it doesn't work either.

Thank you,

Jixiang Wu



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Re: [R] list.dir() function

2011-11-12 Thread Scott
firstly - it looks like you define orgDir but then your code later refers to
indexDir? that being said, I don't think that is relevant.

You could always try upgrading to the latest version and see if the problem
goes away (if you're not already).

I can't replicate the issue here but we can't guess what version you're
running of R. It's always helpful to include What build/operating system
etc. Use the following command and copy and paste. into your reply please. 

R.version

One option you've got perhaps is to indexDir into the directory and then try
the same commands you've mentioned in your post.

another option which might work would be based on these two lines.

a1-file.info(list.files(indexDir))
mydir-row.names(a1[a1$isdir==TRUE,])

let me know if you can't get it. I don't know why your code doesn't work.

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Re: [R] changelog for MASS?

2011-11-12 Thread R. Michael Weylandt
It's on CRAN, where you can also see the record of updates:
http://cran.r-project.org/web/packages/MASS/index.html

Specifically, http://cran.r-project.org/web/packages/MASS/NEWS

Hope this helps

On Sat, Nov 12, 2011 at 8:55 AM, Xu Wang xuwang...@gmail.com wrote:
 Does anyone know where I can find a changelog for MASS?

 It's difficult to know whether I should ask my company to update the package
 or not. We are usually required to show the changelog, but I can't find one.

 Thank you,

 Xu

 --
 View this message in context: 
 http://r.789695.n4.nabble.com/changelog-for-MASS-tp4034473p4034473.html
 Sent from the R help mailing list archive at Nabble.com.

 __
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 https://stat.ethz.ch/mailman/listinfo/r-help
 PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
 and provide commented, minimal, self-contained, reproducible code.


__
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Re: [R] With an example - Re: rbind.data.frame drops attributes for factor variables

2011-11-12 Thread David Winsemius


On Nov 12, 2011, at 2:47 PM, Sammy Zee wrote:


When I use rbind() or rbind.data.frame() to add a row to an existing
dataframe, it appears that attributes for the column of type  
factor are

dropped. See the sample example below to reproduce the problem. Please
suggest How I can fix this.




Thanks,
Sammy

a=c(Male, Male, Female, Male)
b=c(1,2,3,4)
c=c(great, bad, good, bad)
dataset- data.frame (gender = a, count = b, answer = c)


dataset


gender count answer
1   Male 1  great
2   Male 2bad
3 Female 3   good
4   Male 4bad



attributes(dataset$answer)

$levels
[1] bad   good  great

$class
[1] factor

Now adding some custom attributes to column dataset$answer

attributes(dataset$answer)-c(attributes(dataset 
$answer),list(newattr1=custom-attr1))
attributes(dataset$answer)-c(attributes(dataset 
$answer),list(newattr2=custom-attr2))


If you look through the code of rbind.data.frame you see that column  
values are processed with the 'factor' function.


 attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

$newattr1
[1] custom-attr1

$newattr2
[1] custom-attr2

 attributes(factor(dataset$answer))
$levels
[1] bad   good  great

$class
[1] factor


So I think you are out of luck. You will need to restore the special  
attributes yourself.


--
David.



attributes(dataset$answer)

$levels
[1] bad   good  great

$class
[1] factor

$newattr1
[1] custom-attr1

$newattr2
[1] custom-attr2

However as soon as I add a row to this data frame (dataset) by  
rbind(),

it loses the custom
attributes (newattr1 and newattr2) I have just added

newrow = c(gender=Female, count = 5, answer = great)

dataset - rbind(dataset, newrow)


attributes(dataset$answer)

$levels
[1] bad   good  great

$class
[1] factor

the two custom attributes are dropped!! Any suggestion why this is
happening.

On Fri, Nov 11, 2011 at 11:44 AM, Jeff Newmiller
jdnew...@dcn.davis.ca.uswrote:


As the doctor says, if it hurts don't do that.

A factor is a sequence of integers with a corresponding list of  
character
strings. Factors in two separate vectors can and usually do map the  
same
integer to different strings, and R cannot tell how you want that  
resolved.


Convert these columns to character before combining them, and only  
convert
to factor when you have all of your possibilities present (or you  
specify

them in the creation of the factor vector).
---
Jeff NewmillerThe .   .  Go  
Live...

DCN:jdnew...@dcn.davis.ca.usBasics: ##.#.   ##.#.  Live
Go...
Live:   OO#.. Dead: OO#..   
Playing

Research Engineer (Solar/BatteriesO.O#.   #.O#.  with
/Software/Embedded Controllers)   .OO#.   .OO#.   
rocks...1k

---
Sent from my phone. Please excuse my brevity.

Sammy Zee szee2...@gmail.com wrote:


Hi all,

When I use rbind() or rbind.data.frame() to add a row to an existing
dataframe, it appears that attributes for the column of type  
factor

are
dropped. I see the following post with same problem. However i did  
not

see
any reply to the following posting offering a solution. Could  
someone

please help.



http://r.789695.n4.nabble.com/rbind-data-frame-drops-attributes-for-factor-variables-td919575.html


Thanks,
Sammy

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David Winsemius, MD
West Hartford, CT

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Re: [R] Second-order effect in Parametric Survival Analysis

2011-11-12 Thread David Winsemius


On Nov 12, 2011, at 7:37 AM, ryusuke wrote:


Hi experts,

http://r.789695.n4.nabble.com/file/n4034318/Parametric_survival_analysis_2nd-order_efffect.JPG
Parametric_survival_analysis_2nd-order_efffect.JPG
As we know a normal survival regression is the equation (1)
Well, I'ld like to modify it to be 2nd-order interaction model as  
shown in

equation(2)

Question:
Assume a and z is two covariates.
x = dummy variable (1 or 0)
z = factors (peoples' name)
fit - survreg(Surv(time,censor)~x*z, data=sample, dist=exponential)

I tried to apply survreg(), while I have few questions:
1) If */survreg(Surv(time,censor)~x*z, data=sample,  
dist=exponential)/*

correct?


The formula interface for R would expand x*z to x + z + x:z (Which is  
not the formula in your Nabble-provided-jpg, but from your later   
questions is probably what you want anyway.)



2) If the baseline hazard is the value excluded both x and z effects?


Maybe. You won't be  excluding them so much as holding their values  
jointly at zero, which may or may not be the same thing.



3) How can I get the value and plot the hazard with only x effect (but
exclude effect z)


You will never be able to do so. If you have an interacting variable  
in a model, there will always be an effect of that covariate on  
predictions associated with any covariate with which it is  
interacting. You should be able to display or plot the x- 
effects (note the plural) that are estimated for chosen levels of z,  
however. To accomplish that you should construct an appropriate  
data.frame and offer it as the newdata argument to predict(fit)   
just as you would do with any properly constructed R/S regression  
package.


There is a worked example on this posting from the Master:

http://finzi.psych.upenn.edu/Rhelp10/2010-May/240458.html

--
David Winsemius, MD
West Hartford, CT

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[R] dev.new() within a loop

2011-11-12 Thread Giovanni Azua
Hello,

I have a loop where I iterate performance data files within a folder, parse and 
plot them in one shot (see below).

However, when executing plot_raw which invokes dev.new(..) all windows come out 
blank whereas if I execute each file outside of a loop then I can see the plots 
properly. What's wrong here?

Thanks in advance,
Best regards,
Giovanni

# given a directory name, it will iterate all files that match the given pattern
#basedir - /Users/bravegag/code/asl11/data/2k-r1-test-2011_data/
basedir - /Users/bravegag/code/asl11/data/nclients_2_128-2010_data/
pattern - paste(logs.*cl\\-.*mw\\-.*db\\-.*\\-client\\.dat,sep=)
all_files - dir(path=basedir, pattern=pattern)

throughput - NULL
response - NULL

#file_name - all_files[1]

# iterate all files
for (file_name in all_files) {
print(paste(processing, file_name, ...))

df - read.table(paste(basedir, file_name, sep=))  # read 
the data as a data frame
names(df)[names(df)==V1] - Time
names(df)[names(df)==V2] - Partitioning
names(df)[names(df)==V3] - Workload
names(df)[names(df)==V4] - Runtime

# get rid of first and last n minutes 
df - subset(df, df$Time  warmup_cooldown_minutes)
df - subset(df, df$Time  (max(df$Time) - warmup_cooldown_minutes))

# 
=
# Throughput
# 
=
if (decouple) {
dft - aggregate(x=df$Runtime, by=list(df$Time,df$Workload), 
FUN=length)
names(dft)[names(dft)==Group.1] - Time   
names(dft)[names(dft)==Group.2] - Workload
names(dft)[names(dft)==x] - Y

} else {
dft - aggregate(x=df$Runtime, by=list(df$Time), FUN=length)
names(dft)[names(dft)==Group.1] - Time   
names(dft)[names(dft)==x] - Y
}
dft$se - 0
plot_raw(dft,connect=TRUE,label=file_name)
}
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Re: [R] With an example - Re: rbind.data.frame drops attributes for factor variables

2011-11-12 Thread Sammy Zee
Thanks David. Besides rbind(), is there any other way to add a row to a
data frame so that I do not lose the custom attributes.

Thanks,
Sammy

On Sat, Nov 12, 2011 at 5:17 PM, David Winsemius dwinsem...@comcast.netwrote:


 On Nov 12, 2011, at 2:47 PM, Sammy Zee wrote:

  When I use rbind() or rbind.data.frame() to add a row to an existing
 dataframe, it appears that attributes for the column of type factor are
 dropped. See the sample example below to reproduce the problem. Please
 suggest How I can fix this.


  Thanks,
 Sammy

 a=c(Male, Male, Female, Male)
 b=c(1,2,3,4)
 c=c(great, bad, good, bad)
 dataset- data.frame (gender = a, count = b, answer = c)

  dataset


 gender count answer
 1   Male 1  great
 2   Male 2bad
 3 Female 3   good
 4   Male 4bad


  attributes(dataset$answer)

 $levels
 [1] bad   good  great

 $class
 [1] factor

 Now adding some custom attributes to column dataset$answer

 attributes(dataset$answer)-c(**attributes(dataset$answer),**
 list(newattr1=custom-attr1))
 attributes(dataset$answer)-c(**attributes(dataset$answer),**
 list(newattr2=custom-attr2))


 If you look through the code of rbind.data.frame you see that column
 values are processed with the 'factor' function.


  attributes(dataset$answer)
 $levels
 [1] bad   good  great

 $class
 [1] factor

 $newattr1
 [1] custom-attr1

 $newattr2
 [1] custom-attr2

  attributes(factor(dataset$**answer))

 $levels
 [1] bad   good  great

 $class
 [1] factor


 So I think you are out of luck. You will need to restore the special
 attributes yourself.

 --
 David.


  attributes(dataset$answer)

 $levels
 [1] bad   good  great

 $class
 [1] factor

 $newattr1
 [1] custom-attr1

 $newattr2
 [1] custom-attr2

 However as soon as I add a row to this data frame (dataset) by rbind(),
 it loses the custom
 attributes (newattr1 and newattr2) I have just added

 newrow = c(gender=Female, count = 5, answer = great)

 dataset - rbind(dataset, newrow)

  attributes(dataset$answer)

 $levels
 [1] bad   good  great

 $class
 [1] factor

 the two custom attributes are dropped!! Any suggestion why this is
 happening.

 On Fri, Nov 11, 2011 at 11:44 AM, Jeff Newmiller
 jdnew...@dcn.davis.ca.us**wrote:

  As the doctor says, if it hurts don't do that.

 A factor is a sequence of integers with a corresponding list of character
 strings. Factors in two separate vectors can and usually do map the same
 integer to different strings, and R cannot tell how you want that
 resolved.

 Convert these columns to character before combining them, and only
 convert
 to factor when you have all of your possibilities present (or you specify
 them in the creation of the factor vector).
 --**--**
 ---
 Jeff NewmillerThe .   .  Go
 Live...
 DCN:jdnew...@dcn.davis.ca.usBasics: ##.#.   ##.#.  Live
 Go...
Live:   OO#.. Dead: OO#..  Playing
 Research Engineer (Solar/BatteriesO.O#.   #.O#.  with
 /Software/Embedded Controllers)   .OO#.   .OO#.
  rocks...1k
 --**--**
 ---
 Sent from my phone. Please excuse my brevity.

 Sammy Zee szee2...@gmail.com wrote:

  Hi all,

 When I use rbind() or rbind.data.frame() to add a row to an existing
 dataframe, it appears that attributes for the column of type factor
 are
 dropped. I see the following post with same problem. However i did not
 see
 any reply to the following posting offering a solution. Could someone
 please help.


  http://r.789695.n4.nabble.com/**rbind-data-frame-drops-**
 attributes-for-factor-**variables-td919575.htmlhttp://r.789695.n4.nabble.com/rbind-data-frame-drops-attributes-for-factor-variables-td919575.html


 Thanks,
 Sammy

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 PLEASE do read the posting guide http://www.R-project.org/**
 posting-guide.html http://www.R-project.org/posting-guide.html
 and provide commented, minimal, self-contained, reproducible code.


 David Winsemius, MD
 West Hartford, CT



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Re: [R] efpFunctional construction (strucchange package)

2011-11-12 Thread bonda
Unfortunately, I couldn't find neither this source file, nor function wmax().
Was it any old version of strucchange? There are only files strucchange.R,
strucchange.rdb and strucchange.rdx in directory \strucchange\R.

Best,
Julia

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and provide commented, minimal, self-contained, reproducible code.


[R] Simulation over data repeatedly for four loops

2011-11-12 Thread Francesca
Dear Contributors,

I am trying to perform a simulation over sample data,

but I need to reproduce the same simulation over 4 groups of data. My
ability with for loop is null, in particular related

to dimensions as I always get, no matter what I try,

number of items to replace is not a multiple of replacement length


This is what I intend to do: replicate this operation for

four times, where the index for the four groups is in the

part of the code: datiPc[[1]][,2].

I have to replicate the following code 4 times, where the

changing part is in the data from which I pick the sample,

the data that are stored in datiPc[[1]][,2].

If I had to use data for the four samples, I would substitute the 1 with a
j and replicate a loop four times, but it never worked.


My desired final outcome is a matrix with 1 observations for each
couple of extracted samples, i.e. 8 columns of 1 observations of means.



db-c()

# Estrazione dei campioni dai dati di PGG e TRUST

estr1 - c();

estr2 - c();

m1-c()

m2-c()

   tmp1- data1[[1]][,2];

  tmp2- data2[[2]][,2];

for(i in 1:100){

estr1-sample(tmp1, 1000, replace = TRUE)

estr2-sample(tmp2, 1000, replace = TRUE)


m1[i]-mean(estr1,na.rm=TRUE)

m2[i]-mean(estr2,na.rm=TRUE)

}

db-data.frame(cbind(m1,m2))
Thanks for any help you can provide.
Best Regards

-- 

Francesca
--

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Re: [R] With an example - Re: rbind.data.frame drops attributes for factor variables

2011-11-12 Thread David Winsemius


On Nov 12, 2011, at 6:40 PM, Sammy Zee wrote:

Thanks David. Besides rbind(), is there any other way to add a row  
to a data frame so that I do not lose the custom attributes.


I have already told you the method that I know of. You don't seem to  
have taken my poin that it is not a data.frame specific problem but  
rahter a facor problem. You are welcome to redefine  
`rbind.data.frame`. The R language is rather flexible in that manner.


--
David.



Thanks,
Sammy

On Sat, Nov 12, 2011 at 5:17 PM, David Winsemius dwinsem...@comcast.net 
 wrote:


On Nov 12, 2011, at 2:47 PM, Sammy Zee wrote:

When I use rbind() or rbind.data.frame() to add a row to an existing
dataframe, it appears that attributes for the column of type  
factor are

dropped. See the sample example below to reproduce the problem. Please
suggest How I can fix this.


Thanks,
Sammy

a=c(Male, Male, Female, Male)
b=c(1,2,3,4)
c=c(great, bad, good, bad)
dataset- data.frame (gender = a, count = b, answer = c)

dataset

gender count answer
1   Male 1  great
2   Male 2bad
3 Female 3   good
4   Male 4bad


attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

Now adding some custom attributes to column dataset$answer

attributes(dataset$answer)-c(attributes(dataset 
$answer),list(newattr1=custom-attr1))
attributes(dataset$answer)-c(attributes(dataset 
$answer),list(newattr2=custom-attr2))


If you look through the code of rbind.data.frame you see that column  
values are processed with the 'factor' function.



 attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

$newattr1
[1] custom-attr1

$newattr2
[1] custom-attr2

 attributes(factor(dataset$answer))

$levels
[1] bad   good  great

$class
[1] factor


So I think you are out of luck. You will need to restore the  
special attributes yourself.


--
David.


attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

$newattr1
[1] custom-attr1

$newattr2
[1] custom-attr2

However as soon as I add a row to this data frame (dataset) by  
rbind(),

it loses the custom
attributes (newattr1 and newattr2) I have just added

newrow = c(gender=Female, count = 5, answer = great)

dataset - rbind(dataset, newrow)

attributes(dataset$answer)
$levels
[1] bad   good  great

$class
[1] factor

the two custom attributes are dropped!! Any suggestion why this is
happening.

On Fri, Nov 11, 2011 at 11:44 AM, Jeff Newmiller
jdnew...@dcn.davis.ca.uswrote:

As the doctor says, if it hurts don't do that.

A factor is a sequence of integers with a corresponding list of  
character
strings. Factors in two separate vectors can and usually do map the  
same
integer to different strings, and R cannot tell how you want that  
resolved.


Convert these columns to character before combining them, and only  
convert
to factor when you have all of your possibilities present (or you  
specify

them in the creation of the factor vector).
---
Jeff NewmillerThe .   .  Go  
Live...


Sammy Zee szee2...@gmail.com wrote:

Hi all,

When I use rbind() or rbind.data.frame() to add a row to an existing
dataframe, it appears that attributes for the column of type factor
are
dropped. I see the following post with same problem. However i did not
see
any reply to the following posting offering a solution. Could someone
please help.


http://r.789695.n4.nabble.com/rbind-data-frame-drops-attributes-for-factor-variables-td919575.html

Thanks,
Sammy

[[alternative HTML version deleted]]

___



David Winsemius, MD
West Hartford, CT

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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.


Re: [R] dev.new() within a loop

2011-11-12 Thread David Winsemius


On Nov 12, 2011, at 6:04 PM, Giovanni Azua wrote:


Hello,

I have a loop where I iterate performance data files within a  
folder, parse and plot them in one shot (see below).


However, when executing plot_raw which invokes dev.new(..) all  
windows come out blank whereas if I execute each file outside of a  
loop then I can see the plots properly.


Perhaps ...(you did not say what package this plot_raw function comes  
from) ...  Read the FAQ about why lattice plot don't print. (It  
applies to all grid based plotting functions.)


--
David


What's wrong here?

Thanks in advance,
Best regards,
Giovanni

# given a directory name, it will iterate all files that match the  
given pattern
#basedir - /Users/bravegag/code/asl11/data/2k-r1- 
test-2011_data/
basedir - /Users/bravegag/code/asl11/data/ 
nclients_2_128-2010_data/

pattern - paste(logs.*cl\\-.*mw\\-.*db\\-.*\\-client\\.dat,sep=)
all_files - dir(path=basedir, pattern=pattern)

throughput - NULL
response - NULL

#file_name - all_files[1]

# iterate all files
for (file_name in all_files) {
print(paste(processing, file_name, ...))

	df - read.table(paste(basedir, file_name, sep=))  #  
read the data as a data frame

names(df)[names(df)==V1] - Time
names(df)[names(df)==V2] - Partitioning
names(df)[names(df)==V3] - Workload
names(df)[names(df)==V4] - Runtime

# get rid of first and last n minutes
df - subset(df, df$Time  warmup_cooldown_minutes)
df - subset(df, df$Time  (max(df$Time) - warmup_cooldown_minutes))

	#  
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
==

# Throughput
	#  
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
==

if (decouple) {
		dft - aggregate(x=df$Runtime, by=list(df$Time,df$Workload),  
FUN=length)

names(dft)[names(dft)==Group.1] - Time
names(dft)[names(dft)==Group.2] - Workload
names(dft)[names(dft)==x] - Y

} else {
dft - aggregate(x=df$Runtime, by=list(df$Time), FUN=length)
names(dft)[names(dft)==Group.1] - Time
names(dft)[names(dft)==x] - Y
}
dft$se - 0
plot_raw(dft,connect=TRUE,label=file_name)
}
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and provide commented, minimal, self-contained, reproducible code.


David Winsemius, MD
West Hartford, CT

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[R] Myriam Saavedra M. Sc. Questions about maximun radius distance

2011-11-12 Thread Myriam
Dear Mr. Baddeley
 
I just graduated from a Masters in Applied Mathematics on Jun19th. My thesis 
was about spatial distribution /a nalysis of some trees in a part of  the Congo 
Basic Forest.
In my thesis I used your spatial package in R, and today I'm doing a more 
deeper study about how we choise the r distance in Function F(). I would like to
be able to understand about value of rmaxdefault as:
 
ripley - min(diff(W$xrange), diff(W$yrange))/4
rlarge - if (!missing(lambda)) sqrt(1000/(pi * lambda)) else Inf
rmax - min(rlarge, ripley)

 For the ripley's calculation, I found your explanation in the internet but 
for the rlarge I couldn't find it. Could you explain why it is using the 
value inside of the sqrt (1000/(pi * lambda)).
 
Many thanks in advance if you do have the time to answer,
 
Myriam Saavedra  
Universidad San Francisco de Quito
...
Adress Home
3808 Lillooet St.
VANCOUVER BC
CANADA, V5R-2E6

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[R] identify duplicate from more than one column

2011-11-12 Thread jour4life
Hi all,

I've searched everywhere to try to find out how to do this and have had no
luck. I am trying to construct identifiers for couples in a dataset.
Essentially, I want to identify couples using more than one column as
identifiers. Take for instance:

obs unithome   zsex age
1   015029  18 11   053
2   015029  18 12   049
3   015029  01 11   038
4   015029  01 12   033
5   015029  02 11   036
6   015029  02 12   033
7   015029  03 11   023
8   015029  03 12   019
9   015029  04 12   045
10  015029  05 12   047

Where unit is the housing unit, home is household. Of course, there are more
values for unit, although these first ten observations consist of the same
unit (which could possibly be an apartment complex). Nonetheless, I want to
construct an identifier for couples if unit, home match, but only if both
male and female are within the same household. Taking the example data
above, I want to see this:

unithomez   sex age  couple
1   015029  18 11   053  1
2   015029  18 12   049  1
3   015029  01 11   038  2
4   015029  01 12   033  2
5   015029  02 11   036  3
6   015029  02 12   033  3
7   015029  03 11   023  4
8   015029  03 12   019  4
9   015029  04 12   045  0
10  015029  05 12   047  0

As you can see in the last two observations, there were no males identified
within the same household, thus the last two observations would not contain
couple identifiers, rather some other identifier (but the same one) so I can
detect them and remove them later. I've tried using the duplicated function
but was not very useful.

Any help would be greatly appreciated!!! 

Thanks,

Carlos

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Re: [R] identify duplicate from more than one column

2011-11-12 Thread Joshua Wiley
Hi Carlos,

Here is one option:

## read in your data
dat - read.table(textConnection(
obs unithome   zsex age
1   015029  18 11   053
2   015029  18 12   049
3   015029  01 11   038
4   015029  01 12   033
5   015029  02 11   036
6   015029  02 12   033
7   015029  03 11   023
8   015029  03 12   019
9   015029  04 12   045
10  015029  05 12   047),
  header = TRUE, stringsAsFactors = FALSE)
closeAllConnections()

## create a unique ID for matching unit and home
dat$mID - with(dat, paste(unit, home, sep = ''))

## somewhat messy way of creating a couple number
## for each mID, if there is more than 1 row, and more than 1 sex
## it creates a couple id, otherwise 0
i - 0L
dat$couple - with(dat, unlist(lapply(split(sex, mID), function(x) {
  i - i + 1L
  if (length(x)  1  length(unique(x))  1) {
rep(i, length(x))
  } else 0L
})))

## view results
dat
   obs  unit home z sex age mID couple
11 15029   18 1   1  53 1502918  1
22 15029   18 1   2  49 1502918  1
33 150291 1   1  38  150291  2
44 150291 1   2  33  150291  2
55 150292 1   1  36  150292  3
66 150292 1   2  33  150292  3
77 150293 1   1  23  150293  4
88 150293 1   2  19  150293  4
99 150294 1   2  45  150294  0
10  10 150295 1   2  47  150295  0

See these functions for more details:

?ave # where I got my idea
?split
?lapply
?`-`

Cheers,

Josh

On Sat, Nov 12, 2011 at 8:16 PM, jour4life jour4l...@gmail.com wrote:
 Hi all,

 I've searched everywhere to try to find out how to do this and have had no
 luck. I am trying to construct identifiers for couples in a dataset.
 Essentially, I want to identify couples using more than one column as
 identifiers. Take for instance:

 obs     unit            home       z    sex     age
 1       015029  18             1        1       053
 2       015029  18             1        2       049
 3       015029  01             1        1       038
 4       015029  01             1        2       033
 5       015029  02             1        1       036
 6       015029  02             1        2       033
 7       015029  03             1        1       023
 8       015029  03             1        2       019
 9       015029  04             1        2       045
 10      015029  05             1        2       047

 Where unit is the housing unit, home is household. Of course, there are more
 values for unit, although these first ten observations consist of the same
 unit (which could possibly be an apartment complex). Nonetheless, I want to
 construct an identifier for couples if unit, home match, but only if both
 male and female are within the same household. Taking the example data
 above, I want to see this:

        unit            home    z       sex     age      couple
 1       015029  18             1        1       053      1
 2       015029  18             1        2       049      1
 3       015029  01             1        1       038      2
 4       015029  01             1        2       033      2
 5       015029  02             1        1       036      3
 6       015029  02             1        2       033      3
 7       015029  03             1        1       023      4
 8       015029  03             1        2       019      4
 9       015029  04             1        2       045      0
 10      015029  05             1        2       047      0

 As you can see in the last two observations, there were no males identified
 within the same household, thus the last two observations would not contain
 couple identifiers, rather some other identifier (but the same one) so I can
 detect them and remove them later. I've tried using the duplicated function
 but was not very useful.

 Any help would be greatly appreciated!!!

 Thanks,

 Carlos

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-- 
Joshua Wiley
Ph.D. Student, Health Psychology
Programmer Analyst II, ATS Statistical Consulting Group
University of California, Los Angeles
https://joshuawiley.com/

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Re: [R] Second-order effect in Parametric Survival Analysis

2011-11-12 Thread ryusuke
Thank you Dr. David.

I try to summarize it.
Assumes x and z are two covariates:
x = dummy variable (1 or 0)
z = factors (people name)

x*z = x + z + x*z
therefore this is not a 2nd-order interactions, it should be (for an
exponential survival regression):-
h(t|(X=x,Z=z)) = exp(Beta0 + XZBeta1)

#---

I believe there is no 2nd-order interactions survival regression as I
searched over www.rseek.org. While I tried to read through the codes of
survreg(), I stuck (cannot understand) at survreg6.c

survreg6.c apply C Language which involves Cholesky decomposition
multi-matrix (first-order interactions) calculation.
1) chinv2.c
2) cholesky3.c
3) chsolve2.c (only solve the equations of first-order interactions)

If someone gives some idea or suggestion on these?
Thank you.


Best,
Ryusuke


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