search for: stochast

Hi, Given a positive integer N, and a real number \lambda such that 0 < \lambda < 1, I would like to generate an N by N stochastic matrix (a matrix with all the rows summing to 1), such that it has the second largest eigenvalue equal to \lambda (Note: the dominant eigenvalue of a stochastic matrix is 1). I don't care what the other eigenvalues are. The second eigenvalue is important in that it governs the rate at...

...t;. In a deterministic model {i.e., transition matrix is defined as A <- matrix(c(0.70, 0.70,0.35,0.50), nrow=2,byrow=TRUE}, population growth rate can be estimated from the dominant eigenvalue {command "eigen.analysis"}. However, I cannot figure out the way to compute the asymptotic stochastic population growth rate using ?popbio?. I would like to perform a stochastic model in which my demographic rates are sampled from beta distribution with known mean and SD. For example, rather than 0.50 (4th term of my matrix), I want to sample this parameter from a beta function at each time-step...

Hi. guys, I am trying to write my own Stochastic Gradient Ascent for logistic regression in R. But it seems that I am having convergence problem. Am I doing anything wrong, or just the data is off? Here is my code in R - lbw <- read.table("http://www.biostat.jhsph.edu/~ririzarr/Teaching/754/lbw.dat" , header=TRUE) attach(lbw...

Hello R users, I am trying to calculate the stochastic lambda for a published matrix population model using the popbio package. Unfortunately, I have been unable to match the published results. Can anyone tell me whether this is due to slightly different methods being used, or have I gone wrong somewhere in my code? Could the answer be as simple...

...rror message and the C codes are shown below. Could you give me some suggestions? Thanks a lot for your help. ************************************************************************* *************** error message ********************************** Linking... Creating library Release/stochastic.lib and object Release/stochastic.exp stochastic.obj : error LNK2001: unresolved external symbol _PutRNGstate stochastic.obj : error LNK2001: unresolved external symbol _unif_rand stochastic.obj : error LNK2001: unresolved external symbol _Rf_rnorm stochastic.obj : error LNK2001: unresolved exter...

Hi, I am trying to find out the scale efficiency and optimal scale of banks by stochastic frontier analysis given the panel data of bank. I am free to choose any model of stochastic frontier analysis. The only approach I know to work with R is to estimate a translog production function by sfa or other related function in frontier package, and then use the Ray 1998 formula to find...

Hi all, Does anybody have the source code of stochastic volatility models in R or Matlab, for example, the Bayesian based or the simulation based SV estimations as described by Prof Eric Zivot in the following discussion? https://stat.ethz.ch/pipermail/r-sig-finance/2005q4/000501.html -------------- I am wondering what is the current status of esti...

I need to estimate maximum tree crown radius and am looking for a package to prepare stochastic frontier models in R. I have not found any package references on Nabble R help, google, or R help. Any tips on a package for this? With regards, Aaron Trowbridge Researcher BV Research Centre Smithers B.C. -- View this message in context: http://www.nabble.com/package-for-stochastic-fron...

Hello, It's not easy to express clearly what I have in mind by stochastic growth models. I've been working with a couple of titles -Stochastic Models in Biology, for one, but both date back a decade or more. I'll try to illustrate the model a little more. A reasonably comparable situation is Bolker's analysis of how many flowers are created on a given plan...

Dear all, I want to finished my paper by latent class Stochastic Frontier Analysis , but i can not find the package, is there anyone that may help me Thanks a lot. [[alternative HTML version deleted]]

(apologies for the cross-posting, and for this being a more general stats question rather than a specific-to-R one. I assure you I will be doing the actual analysis in R :) I am trying to determine the distribution and variance for a classic stochastic (transition) matrix problem such that: let x(t) be an initial state vector consisting of counts of classes A, B and C: x(t) = [A(t),B(t),C(t)] T is the stochastic (transition) matrix for these classes consisting of the transition probabilities between each combination of A,B and C: pAA...

Hi! A few weeks ago, I have uploaded a new R package "frontier" for Stochastic Frontier Analysis (SFA) [1] to CRAN [2]. It includes the FORTRAN code of Tim Coelli's [3] software "Frontier 4.1" [4]. Hence, the R package "frontier" should have the same capabilities as "Frontier 4.1", i.e. Maximum Likelihood Estimation of Stochastic Fronti...

Dear colleagues, I?m a new R-help user. I?ve read the advertisements about the good manners and I hope to propose a good question. I?m using R to build an epidemiological SEIR model based on ODEs. The odesolve package is very useful to solve deterministic ODE systems but I?d like to perform a stochastic simulation based on Markov chain Montecarlo methods. I don?t know which packages could be used to do it (I tried with "sde" but without results). Have you some suggestions about useful methods and/or function in R for reaching my aim. Thanks in advance. Max MASSIMO FENATI (DVM)...

Hi all, Could anybody point me to some overview/survey papers about using particle filters and sequential monte carlo methods to estimate stochastic volatilities? I couldn't find any such articles giving a big-picture view of the literature. How do these estimation methods compare to EMM and other Bayesian methods for estimating stochastic volatilities? Also, I am looking for some sample/source code that shows how to program particle fi...

Hi! A few weeks ago, I have uploaded a new R package "frontier" for Stochastic Frontier Analysis (SFA) [1] to CRAN [2]. It includes the FORTRAN code of Tim Coelli's [3] software "Frontier 4.1" [4]. Hence, the R package "frontier" should have the same capabilities as "Frontier 4.1", i.e. Maximum Likelihood Estimation of Stochastic Fronti...

Dear all, I want to program my own models about Stochastic Frontier Analysis and Linear programming (Data Envelopment Analysis). In this context, is there anyone that may help me with some simple tutorials and scripts about these issues? Thanks a lot. -- Marcus Vinicius Pereira de Souza, Prof. [[alternative HTML version deleted]]

I am interested in creating multiple (say 1000) time series, from a given stochastic process, of length 250. I want to refer to each realization with its own variable name, of the format say, tsn, where n is the n'th simulation. i.e. ts1, ts2, ts3, ts4, .... , ts1000 The way I am thinking of doing this is placing the following code within another loop, and the 'tsn'...

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.

Dear everyone, i`m a german economics student, writing my master´s thesis about "Multivariate Volatility Models". After having read about theoretical aspects of Multivariate GARCH ans Stochastic Volatility Models, I would like to compare DCC-GARCH and DC-SV with help of an empirical application. I figuered out that one has to use MCMC-simulation-methods for that. Some days ago I started searching the internet for already written codes... without any succes. The only code I found is from...

Do anyone now R packages that run/test stochastic dominance with respect to a function (SDRF) and/or stochastic efficiency with respect to a function (SERF)? Peter Maclean Department of Economics UDSM [[alternative HTML version deleted]]