similar to: simple loop problemo (Geo brownian motion)

Hi, I have been using maxLik to do some MLE of Geometric Brownian Motion Process and everything has been going fine, but know I have tried to do it with jumps. I have create a vector of jumps and then added this into my log-likelihood equation, know I am getting a message: NA in the initial gradient My codes is hear # n<-length(combinedlr) j<-c(1,2,3,4,5,6,7,8,9,10)

Dear R Helpers, I have searched for any R package or code for simulating multivariate fractional Brownian motion (mFBM) or multivariate fractional Gaussian noise (mFGN) when a covariance matrix are given. Unfortunately, I could not find such a package or code. Can you suggest any solution for multivariate FBM and FGN simulation? Thank you for your help. Best Regards, Ryan ----- Wonsang You

Hi list, I'm trying to generate fractional brownian surfaces in R. [A detailed description with respect to various techniques to generating these neutral landscapes has been described by Timothy Keitt (spectral representation of neutral landscapes, Landscape Ecology, 2000) and probably various other authours.] Are there any packages that deal with this or related items? I've been

Hi, I'm writing a short course tutorial to Browninan Motion/ Langevin Equation. At the end of the theory section I wanted to add a short GNU R example, so the students can play a little around. I already looked in the MASS book (by Venables and Ripley) but I couldn't find any Brownian Motion/ Langevin Equation package. Are there any good packages or tutorials available which cover R and

Dear All; I have used fbmSim to simulate a fbm sequence, however, when I tried to estimate the Hurst effect, none of the nine procedures gave me an answer close enough to the real value, which is 0.5 (n=1000). So, would you please advice, 1. which is the best method to estimate the H among the 9 mehods, R/S, higuchi or Whittle? 2. how to choose the levels (default=50), minnpts, cutoff values or

Hello all, could anyone explain the exact meaning of parameter nproc? Why different values of nproc give so different critical values, i.e. meanL2BB$computeCritval(0.05,nproc=3) [1] 0.9984853 meanL2BB$computeCritval(0.05,nproc=1) [1] 0.4594827 The strucchange-package description gives "integer specifying for which number of processes Brownian motions should be simulated" - do I need

Is there a package that will allow me to fit Brownian motion and Ornstein?Uhlenbeck models of evolution for discrete traits? I know that geiger and ouch have commands for fitting these models for continuous traits, but these aren't suitable for discrete trait evolution, correct? -- View this message in context:

Hi, i need help building a program for the evaluation of a cash or nothing option. The option is written on a stock that today has a price of X. Nine months before i will have this situation: If a<X<b the option pays 3 dollars If X<a or X>b the option pays nothing The price of the title is described by a geometric brownian motion, so i need to start a Montecarlo simulation to find

Hi: I was wondering whether I can find some help for computer simulation of stochastic processes (e.g. Brownian motion), for pedagogicl/instructional purposes. Any help would be appreciated. thanks, Ravi.

I''d like to be able to use a has_many :through association and treat the associations as a list but I''m getting this error when I try an use an acts_as_list method: NoMethodError: undefined method `move_to_bottom'' I''m using edge rails r6786. Here are my domain rules: Activities are things students can do. Units consists of a sequenced list of

Hello, I would appreciate if someone could help me with this query. I would like to plot a line chart of all of the points in a "for" loop. I would also like to plot the final point with a symbol (to show where the random walk ends). Here is the code I am using: Brownian.fn <- function(mu, sigma, T, N){ dt <- T/N t <- c(rep(NA, N)) B1 <- c(rep(NA, N)) B2 <- c(rep(NA,

Good morning! After updating and recompiling my copy of the LLVM trunk I noticed that the line "_passManager.add(llvm::createTailDuplicationPass());" in my code fails with the following assertion: Assertion failed: NormalCtor && "Cannot call createPass on PassInfo without default ctor!", file D:\Workspace\llvmtrunk\include\llvm/PassSupport.h, line 111 This behavior

Hi, Few days ago I installed Email2fax application on my Asterisk box. I works but not in 100 %. Sometimes (to be certain quite often) I don't receive the whole fax. My fax machine cuts off transmission in 1/2 or 1/3 of the page. I read about it on a wiki and some user lists and people say that this behaviour could be cause be the Ghostscript and the conversion to the tiff format, but when I

To R programming experts, I am a undergraduate student, and now doing research personally. I apply diagonal bivariate poisson (R package "bivpois") with stochatics weighted function (refer to dixoncoles97 section 4.5 to 4.7). However I dont know how to fit this stochatical weighted function to the completed bivariate poisson model. I know that some other references for dynamic soccer

Dear all, I'm trying to get a Brownian bridge kernel (kernelbb) for each combination of two consecutive animal locations (see commands below) and put them, with a loop, inside a list. It works well at the beginning but after 42 runs, it appears the following warning : >Error in seq.default(yli[1], yli[2], by = diff(xg[1:2])) :  >  invalid (to - from)/by in seq(.) I looked at the

I am trying to learn how to use the graphics from the lattice package ( and am very new to R). I am trying to replicate the example plot referenced below, by using the lattice xyplot & lpolygon to create panels. I get what appears to be the correct shape of the filled region, but cannot get the position to overlay properly. I have attempted with various settings of position. ( i.e.

Hi all. A friend of mine asked me to assist with an R presentation to the Penn State LUG in a few weeks. The audience will be predominately computer scientists and/or engineers (I suspect) and they are just looking for presentations of good open source software and my friend volunteered R. We are both relatively new to R, so I thought it would be best to ask the list for your opinion....what do

Hi, I have thought a lot about my problem and also posted it on stackexchange, the post can be found here: http://stats.stackexchange.com/questions/44276/how-to-plot-3d-gbm but I have got no useful answer, that's why I trry the last possibility, which is to ask you professional guys. I want to recreate the following picture with my own code, the picture can be found in my other post:

Dear all, I know that my question is somewhat special but I tried several times to solve the problems on my own but I am unfortunately not able to compute the following test statistic using the quantreg package. Well, here we go, I appreciate every little comment or help as I really do not know how to tell R what I want it to do^^ My situation is as follows: I have a data set containing a

Dear all, I have just uploaded to CRAN the version 1.6 of the package 'adehabitat'. Significant changes are listed below: * The package has been reorganized into four parts (see ?adehabitat-package for a description): (i) management of raster maps, (ii) habitat selection / ecological niche analysis, (iii) home range analysis, and (iv) analysis of animals trajects. The package contains