similar to: Off-topic: Comparing standard errors from simulation and analytical model

i am trying to solve a partial differential equation analytically(PDE) in R . i have found some functions that do the stuff numerically. But that will not meet my purpose. is there any function to solve PDE analytically. please help. -- View this message in context: http://r.789695.n4.nabble.com/analytical-solution-of-partial-differential-equation-tp4291618p4291618.html Sent from the R help

Hi, Can the plenty of analytical functions provided by base R and contributed packages be called with ff objects as parameters directly, or do we have to write special version of the functions for ff objects? If it is the latter case, is there a list of functions which support ff objects already. Xiaobo.Gu [[alternative HTML version deleted]]

Frede Aakmann T?gersen wrote: > Perhaps > > http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA266969&Location=U2&doc=GetTRDoc.pdf > > is something that you can use? Thanks a lot - that might help. Rainer > > > > Best regards > > Frede Aakmann T?gersen > Scientist > > > UNIVERSITY OF AARHUS > Faculty of Agricultural Sciences > Dept.

hello users of the SN package, i thought i post here some useful help on R code on the 4 moments for the skew t sampling gives seldom good results for skewness and kurtosis, so one really needs the analytical results, it took me some time to get it from the article Azzalini, A. & Capitanio, A. (2003), Distributions generated by perturbation of symmetry with emphasis on a multivariate

Dear all, My data includes almost three thousand people who rank ten categories into three variables. The simple example below is almost same except I have many missing values. x <- cbind( sample( LETTERS[1:10] , 3000 , replace = TRUE ) , sample( LETTERS[1:10] , 3000 , replace = TRUE ) , sample( LETTERS[1:10] , 3000 , replace = TRUE ) ) I try to figure

Can someone recommend a method to answer the following type of question: Suppose I have a coin with a probability hhh of coming up heads (and 1-hhh of coming up tails) I plan on flipping the coin nnn times (for example, nnn = 500) What is the expected probability or frequency of a run of rrr heads* during the nnn=500 coin flips? Moreover, I would probably (excuse the pun) want the answer for a

Version 1.5 of the MiscPsycho package had been uploaded to CRAN (should hit mirrors in a day or so). This package has a set of functions that may be useful for psychometric applications. The package has been updated to include the following: 1) All functions (where appropriate) now use standard formula arguments 2) All functions now use S3 print and summary methods 3) Help files have been

Dear R-Listers, to measure the psychometric curve of pitch discrimination, one sequentially presents two tones of slightly different pitch to an observer (animal will do), and asks "which is higher". The pschometric curve is the fraction of correct responses plotted against the pitch difference. It passes through 50% (pure guessing) at zero and normally approaches 100% at large

hi all, I''ve built a simple javascript datepicker for use with Rails. I''m sure others exist, but think this one is quite decent without being overengineered. http://projects.exactlyoneturtle.com/date_picker/ At present there''s no Rails HTML generator method for it; later I will package it in a script/generator, but for now it is quite easy to use with Rails and

Hi, I have a function of the second grade, with 2 parameters: y~A^2 + A + B^2 + B The response y is a measurement for the precision of the analytical method, where A en B are method parameters. As its neccesary to keep the precision of the analytical methad as good as possible, its usefull to optimize A en B to keep y as low as possible. But how can I do this with R? I have searched the

Hi, What package would you recommend for analyzing the validity/reliability of multiple choice tests. Doing things such as classical test analysis, factor analysis, item response theory. I've used psychometric (item.exam), MiscPsycho (alpha.Summary), and ltm (rcor.test). MiscPsycho reported the numbers most similar to what I get in SPSS: corrected point biserial correlations,

Hi, I want to fit some psychophysical data with cumulative gaussians. There is quite a convenient toolbox for matlab called 'psignifit' (formerly known as 'psychofit'). It allows the lower bound of the sigmoid to vary slightly from zero, aswell as the upper bound to vary from one. with these two free parameters, the fitted function is less sensitive to noisy data and outliers.

Hello please note that the code at https://stat.ethz.ch/pipermail/r-help/2006-August/110892.html to compute indices of skewness and kurtosis for the skew-t distribution is not correct. It has been kindly pointed out that i made some error in this code, which was a bit too quickly copied from the paper. The 'sn' package already contains a facility for computing the cumulants, namely

Hi Roman, On Tue, May 31, 2016 at 9:57 AM, Roman Gareev <gareevroman at gmail.com> wrote: > Hi Tobias, > > I think that we could split a patch that contains an implementation of > tiling, interchanging and unrolling of specific loops into three > separate patches: > > 1. The first one adds a class that describes a processor model. It > also adds a new command line

Hello, I have search on R website but do not find any solution. I would like to know if R has some functionalities to produce analytical results of equation. or more generally if it contains some functions to simplify equation. For example: I would like to obtain x1 from: x1+x2=8 (x1=8-x2) x1^2+x2=8 (x1=sqrt(8-x2)) Is is possible in R ? if not, do you know a (free) software that could do the

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Dear R-Experts, I was wondering how to fit a cumulative gaussian to a set of empirical data using R. On the R website as well as in the mail archives, I found a lot of help on how to fit a normal density function to empirical data, but unfortunately no advice on how to obtain reasonable estimates of m and sd for a gaussian ogive function. Specifically, I have data from a psychometric function

Hi Tobias, I think that we could split a patch that contains an implementation of tiling, interchanging and unrolling of specific loops into three separate patches: 1. The first one adds a class that describes a processor model. It also adds a new command line parameter that contains all necessary parameters of a target architecture, which are used to construct objects of the class. 2. The

Please can someone advise me how I can adjust correlations using bonferroni's correction? I am doing manny correlation tests as part of an investigation of the validity/reliability of a psychometric measure. Help would be so appreciated! Cheers, Louise

Dear R helpers Suppose I have a portfolio of securities with exposure to Equity, Bonds and Forex (say $ 1000000 each). Is there any fucntion in R that will help me calculate Value at Risk (VaR) using Monte carlo Simulation , Historic simulation and Variance - Covariance Simulation. With regards Maithili