similar to: Calling C function in R

I am faced with a situation wherein I have to use multiple lapply's. The pseudo-code could be approximated to something as below: For each X from i=1 to n For each Y based on j=1 to m For each F from 1 to f Do some calculation based on Fij Store Xi,Yj = Fij End For F End for Y End for X Is there anyway to optimize the processing logic further? I *guess* using the multiple lapply

Dear All, Is there any simple way to way to produce "rank", for a given list, but in a descending order? E.G: x = list(a=c(1,5,2,4)); rank(x$a); produces 1,4,2,3 However I am looking for a way to generate (4,1,3,2). It would be particularly nice if the proposed solution has all the niceties of rank function (like NA handling and ties.method functionality) TIA Manoj

Hi, I am trying to do multiple regression on a set of data using backward stepwise regression....however backward stepwise regression is critised for overfitting data. To actually observe the bias and to come up with a better method to use..Could you all stats experts kindly give me pointers to any alternative procedure (or references) to use over backward stepwise regression from your

Dear All, Is it possible to perform OLS using C code? I am trying to optimize a n-period "moving window" OLS on a huge dataset hence was wondering if such a thing is possible. Ideally the solution that I am looking for would involve a C-code accepting two float arrays and returning back computed parameters such as t-stat, coefficient etc. I have glanced thru the FAQ's and tried

Hello everybody, I've got a matrix called EUROPEDATA and I want to calculate the adf test statistic (part of the tseries package) on a rolling basis for window my.win on each column; i.e. each column of EUROPEDATA represents a particular variable; for the first column I calculate the adf test statistic for window my.win = 60 for example, roll forward one observation, calculate the adf

Hello everybody, I have a problem and would like to start with an example: library(snow) library(tseries) fn <- function(x) adf.test(x) clusterApply(cl=cl, x=x , fun=fn) R cannot find the function adf.test() because it is inside the function fn(). This problem does not occur when, for example, fn <- function(x) mean(x) holds. Therefore, I think the package tseries has to be put somehow

Hello All, I am new to R. I am trying to process this huge data set of matrix containing four columns, say x1, x2, x3, x4 and n number of rows. I want to aggregate the matrix by x1 and perform statistic based on columns x2, x3, x4. I tried aggregate function but it gave me memory allocation error (which I am not surprised), so I ended up performing a for loop based on x1 and

I have a question regarding the adf.test command in the tseries library. I have a vector of time series observations (2265 daily log prices for the OEX to be exact). I also have this same data in first-differenced form. I want to test both vectors individually for staionarity with an Augmented Dickey-Fuller test. I noticed when I use the adf.test command from the tseries library, the general

this command is used in tseries adf.test(x, alternative = c("stationary", "explosive"), k = trunc((length(x)-1)^(1/3))) this command apply adf test on data given in x .here general equatiuon that is, equation with constant and trend is used.if i did not include constant or trend in the equation and run the command then how i can run this command in tseries.

Dear Users, please help with the following DF test: ===== library(tseries) library(timeSeries) Y=c(3519,3803,4332,4251,4661,4811,4448,4451,4343,4067,4001,3934,3652,3768 ,4082,4101,4628,4898,4476,4728,4458,4004,4095,4056,3641,3966,4417,4367 ,4821,5190,4638,4904,4528,4383,4339,4327,3856,4072,4563,4561,4984,5316 ,4843,5383,4889,4681,4466,4463,4217,4322,4779,4988,5383,5591,5322,5404

Hi, While doing the ADF test in R using the following command I am getting the error and the result.."> x.ct=ur.df(rev$REVENUE,start=1,end=length(rev$REVENUE),frequency=1) Error in ur.df(rev$REVENUE, start = 1, end = length(rev$REVENUE), frequency = 1) : unused argument(s) (start = 1, end = 4, frequency = 1) >

Short question: Is it possible to use statistical tests, like the Augmented Dickey-Fuller test, in functions with for-loops? If not, are there any alternative ways to scale measures? Detailed explanation: I am working with time-series, and I want to flag curves that are not stationary and which display pulses, trends, or level shifts. >df DATE ID VALUE2012-03-06 1

I am not able to run Dickey-Fuller test. adf.test() function is not working. It is showing 'Error: could not find function "adf.test" Can any tell how to call "time series" library? -- Siddharth Arun, 4th Year Undergraduate student Industrial Engineering and Management, IIT Kharagpur [[alternative HTML version deleted]]

Hi, I am trying to determine the number of units in the hidden layer and the decay rate using the CVnn2 script found in MASS directory (reference: pg 348,MASS-4). The model that I am using is in the form of Y ~ X1 + X2 + X3... + X11 and the underlying data is time-series in nature. I found the MASS and nnet package extremely useful (many thanks to the contributors). However I am getting

Hello all, I tried to extract the p-value from adf.test in tseries; however, I got the error message such as > ht=adf.test(list.var$aa) > ht$p-value Error in ht$p - value : non-numeric argument to binary operator > ht Augmented Dickey-Fuller Test data: list.var$aa Dickey-Fuller = -2.3147, Lag order = 4, p-value = 0.4461 alternative hypothesis: stationary > ht$data [1]

Hi R users, I apologize for a seemingly trivial question, but I felt this forum would be the best place to seek advice. I have been an R user for a year now, but I am limited to using R and its various contributed packages. I strongly feel that users of a free and open source software tool must eventually provide development expertise. I am aware of the extensive documentation available on the

I'm analizing the Argentina stock market (merv) I download the data from yahoo library(tseries) Argentina <- get.hist.quote(instrument="^MERV","1996-10-08","2003-11-03", quote="Close") merv <- na.remove(log(Argentina)) I made the Augmented Dickey-Fuller test to analyse if merv have unit root: adf.test(merv,k=13) Dickey-Fuller = -1.4645,

Dear sir, I am a new user of R statistical package. I want to perform adf.test(augmented dickey fuller test), which packages I need to install in order to perform it. I am getting following message on my monitor. *x<-rnorm(1000) > adf.test(x) Error: could not find function "adf.test" *I am waiting for your response. Kamlesh Kumar. -- Kamlesh Kumar Appt. No. - QQ420,

Hi R users! I've come across using kpss tests for time series analysis and i have a question that troubles me since i don't have much experience with time series and the mathematical part underlining it. x<-c(253, 252, 275, 275, 272, 254, 272, 252, 249, 300, 244, 258, 255, 285, 301, 278, 279, 304, 275, 276, 313, 292, 302, 322, 281, 298, 305, 295, 286, 327, 286, 270, 289, 293, 287,

Hi, While doing the adf test using ur.df ?price.df2=ur.df(y=log(price),type = "drift", selectlags="AIC") summary(price.df2)? It gives two values for ?value of test statistic is: -1.5992?? 2.32? one value is the t-test (or t-ratio), what is the other one? Please help. TIA Aditya