Displaying 20 results from an estimated 800 matches similar to: "R - Confidence Intervals"
2004 Jun 27
1
cross-compiling + expm1
Hello all,
Just joined this mailing list -- not sure if this is the right list to
send this question, but I have a question about cross-compiling R. I am
working with R-1.9.1.tgz.
It may just be with my version of mingw32, but it seems that expm1 is
not defined, so I tried to ensure that HAVE_EXPM1 was #undef'ed before
cross-compiling. The problem is that, in <include/Rmath.h> if
2008 Mar 15
1
feeding merge.zoo a vector containing the names of zoo objects?
Hi, the snippet of code below works, but I would like to know how to feed the
function merge.zoo the contents of
CADstocknames rather than having to hard code it into the merge.zoo command.
I think I must be missing something simple, but I cannot for the life of me
figure it out. Thanks in advance for any enlightenment offered.
library(zoo)
CADstocknames <-
2006 Nov 23
1
Problem with as.ts(zoo-object)
Dear all,
I have an error message, when I try to convert a zoo object (called
test) to ts (on R 2.4.0, Package zoo version 1.2-1, Windows XP)
> test
1994-05-10 1994-06-09 1994-07-09
0.0024943889 0.0024881824 0.0006955831
> str(test)
atomic [1:3] 0.002494 0.002488 0.000696
- attr(*, "index")=Class 'Date' num [1:3] 8895 8925 8955
> is.regular(test)
[1] TRUE
2009 Mar 15
1
cbind(NULL,zoo.object)?
Folks,
I often build up R objects starting from NULL and then repeatedly
using rbind() or cbind(). This yields code like:
a <- NULL
for () {
onerow <- craft one more row
a <- rbind(a, onerow)
}
This works because rbind() and cbind() are forgiving when presented
with a NULL arg: they act like nothing happened, and you get
all.equal(x,rbind(NULL,x)) or all.equal(x,cbind(NULL,x)).
2010 Dec 07
3
help on timeseries
i have time series of momentum signal. I want to get the date of each of the
"-1" signal period. for example , the first period of -1 signal begins on
2005-9-21 and ends on 2005-9-28. 2nd period of -1 signal begins on
2005-09-30 and ends on 2005-10-28.
Thx
Cameron
date Px 200MA Signals
2005-09-15 26.27 25.83865 1
2005-09-16 26.07 25.83275 1
2009 Apr 19
1
dynlm question: How to predefine formula for call to dynlm(formula) call
I want to set up a model with a formula and then run dynlm(formula)
because I ultimately want to loop over a set of formulas (see end of post)
R> form <- gas~price
R> dynlm(form)
Time series regression with "ts" data:
Start = 1959(1), End = 1990(4)
<snip>
Works OK without a Lag term
R> dynlm(gas ~ L(gas,1))
Time series regression with "ts" data:
Start =
2010 Oct 03
2
sampling from normal distribution
Hello
If i want to resampl from the tails of normal distribution , are these commans equivelant??
upper tail:qnorm(runif(n,pnorm(b),1)) if b is an upper tail boundary
or
upper tail:qnorm((1-p)+p(runif(n)) if p is the probability of each interval (the observatins are divided to intervals)
Regards
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2012 Mar 10
1
Generating abnormal returns in R
Hello
This is my first post on this forum and I hope someone can help me out.
I have a datafile (weeklyR) with returns of +- 100 companies.
I acquired this computing the following code:
library("tseries");
tickers = c("GSPC" , "BP" , "TOT" , "ENI.MI" , "VOW.BE" , "CS.PA" ,
"DAI.DE" , "ALV.DE" ,
2011 Dec 17
0
time-varying parameters kalman filter estimation problem using FKF package
Dear R users,
I am trying to carry out MLE of the time-varying CAPM using the FKF package.
My approach so far has been to try and adapt the example given in the help
file found using ?fkf which demonstrates the MLE of an ARMA(2,1) model.
When I attempt to run my R code (given below) I get the following error:
Error in fkf(a0 = sp$a0, P0 = sp$P0, dt = sp$dt, ct = sp$ct, Tt = sp$Tt, :
Some of
2007 May 03
0
Ryacas now on CRAN
Ryacas is now available on CRAN. (Previously it was
available on the Omegahat repository.)
Ryacas is an R package that provides an interface from R to
the yacas computer algebra system. It can be used for
computer algebra, exact arithmetic, ASCII pretty printing
and R to TeX output. R, yacas and Ryacas are all free
software packages distributed under the GPL version 2.
Ryacas is written in R.
2007 May 03
0
Ryacas now on CRAN
Ryacas is now available on CRAN. (Previously it was
available on the Omegahat repository.)
Ryacas is an R package that provides an interface from R to
the yacas computer algebra system. It can be used for
computer algebra, exact arithmetic, ASCII pretty printing
and R to TeX output. R, yacas and Ryacas are all free
software packages distributed under the GPL version 2.
Ryacas is written in R.
2010 Apr 20
1
converting a zoo or an xts to a data frame
Dear R People:
I have the following code that I use to convert a monthly zoo object
to a data.frame, and it works perfectly:
library(tseries)
z <- get.hist.quote(instrument=inst1, start=start1,end=end1,
quote=quot1,comp = "m")
y <- as.ts(aggregate(z, as.yearmon, tail, 1))
y.df <- data.frame(y=y,time=time(y))
y.df$x <- ts(y.df[,1])
tsp(y.df$x) <-
2007 Aug 16
1
time series with quality codes
list(...),
I am working with environmental time series (eg rainfall, stream flow)
that have attached quality codes for each data point. The quality
codes have just a few factor levels, like "good", "suspect", "poor",
"imputed". I use the quality codes in plots and summaries. They are
carried through when a time series is aggregated to a longer
time-step,
2012 Jul 31
2
How can I declare an empty zoo object?
Hi,
I let xzoo be an empty object:
> xzoo<-{}
and I have an existing zoo object x1zoo_f. I would like to combine
the two to make a new zoo object, and continue doing so in a loop,
which is not shown here. However, when I type
> xzoo<-cbind(xzoo, x1zoo_f)
An error message emerges
Error in zoo(structure(x, dim = dim(x)), index(x), ...) :
“x” : attempt to define
2005 Sep 29
2
priceIts
Dear All,
There is an example for the priceIts function (the its package) which
does not work for me as expected.
> ?priceIts
> x1 <- priceIts(instrument = c("^ftse"), start = "1998-01-01",
+ quote = "Close")
Error in validObject(.Object) : invalid class "its" object: Missing
values in dates
> x2 <-
2012 Jun 04
1
probit analysis
Hello!
> I have a very simple set of data and I would like to analyze
> them with probit analysis.
> The data are: X Event Trial
> 1210 8 8
> 121 6 8
> 60.5 6 8
> I want to estimate the value of X that will give a 95% hit
> rate (Event/Trial) and the corresponding 95% CI.
> you can help me? Thanks!!
> Trinh
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2010 Mar 27
0
data fitting and confidence band
Hello,
I am fitting data using different methods e.g. Local Polynomial and Smoothing splines. The data is generated out of a true function model with added normally distributed noise.
I would like to know "how often the confidence band for all points simultaneously contain all true values". I can answer the question for one point in the following way:
e.g.
#
2007 Jun 14
0
Confidence interval for coefficient of variation
This is a function I coded a few years ago to calculate a confidence
interval for a coefficient of variation. The code is based on a paper
by Mark Vangel in The American Statistician. I have not used the
function much, but it could be useful for comparing cv's from
different groups.
Kevin Wright
confint.cv <- function(x,alpha=.05, method="modmckay"){
# Calculate the
2009 Mar 08
0
statistical question: confidence interval of regression weight - significance
hi,
at first; thanks for the help on getting confidence intervals in R.
now I have a pure statistical question.
I hope you don't mind if I ask ...
I have an expectation of how large my beta-weight in a regression
should be - so I have an "ideal" or expected regression line.
Now the real beta-weight is less then the expected and when I draw the
confidence interval lines
2000 Aug 10
1
Confidence intervals
Hi,
I know this is not exactly an R question but may be someone will nice enough to give me a pointer. I'm using nnet to fit a non linear univariate function. I wonder if there is a way to estimate a confidence interval for the predicted output beside using the residuals? The data set I use is relatively small and I use only a few (5:10) of these as test set or should I say validation set.