similar to: generic questions about probability and simulation -- not directly related to R

Displaying 20 results from an estimated 20000 matches similar to: "generic questions about probability and simulation -- not directly related to R"

2013 Nov 04
2
transform one probability distribution into another
Hi guys Given a exponential curve, is there any function on r that can generate exponential distributed random numbers? in General I want an function that can transform one probability distribution into another?? Regards ****************************************************************** Bander ************************************* [[alternative HTML version deleted]]
2003 Jun 25
2
Markov chain simulation
Hi, Does anybody know a function to simulate a Markov chain given a probability transition matrix and an initial state ? Thanks. Philippe -- -------------------------------------------------- Philippe Hup? Institut Curie - Equipe Bioinformatique 26, rue d'Ulm - 75005 PARIS France +33 (0)1 42 34 65 29 Philippe.Hupe at curie.fr <mailto:Philippe.Hupe at curie.fr>
2017 Jun 01
1
Latin Hypercube Sampling when parameters are defined according to specific probability distributions
Thank you very much Rob for your answer. I have some difficulties to understand how to apply my agent-based model to each parameter combination generated by the LHS, in particular when parameters are defined by probability distributions. Indeed, I have multiple parameters in my model: parameters which are defined by a single value (like ?temperature", "pressure?) and parameters which are
2008 Aug 20
1
Simple estimate of a probability by simulation
Hallo I would appreciate any help with the following. Problem: Suppose A, B and C are independent U(0,1) random variables. What is the probability that A(x^2) + Bx + C has real roots? I have done the theoretical work and obtained an answer of 1/9 = 0.1111. Now I want to show my students to get this in R with simulation. Below are two attemps, both giving the answer to be about 0.26. Could
2017 May 27
2
Latin Hypercube Sampling when parameters are defined according to specific probability distributions
>May 26, 2017; 11:41am Nelly Reduan Latin Hypercube Sampling when parameters are >defined according to specific probability distributions >Hello, > I would like to perform a sensitivity analysis using a Latin Hypercube Sampling (LHS). >Among the input parameters in the model, I have a parameter dispersal distance which is defined according to an exponential probability
2008 Aug 21
3
[help] simulation of a simple Marcov Stochastic process for population genetics
Hi, this is my first time using R. I want to simulate the following process: "in a population of size N, there are i individuals bearing genotype A, the number of those bearing A is j in the next generation, which following a binominal distribution (choose j from 2*N, the p is i/2*N), to plot the probability of the next generations, my script is as follows. It cannot run successfully,
2004 Apr 29
3
Probability(Markov chain transition matrix)
Hello, My name is Maria, MBA student in Sanfransisco, USA. In my credit scoring class, I have hard time making "transition matrix", which explains probability especially in relation to "Markov chain model". It is regarding people's monthly credit payment behavior. Does R have function to caculate it? I am actually a novice in using 'R'. Please help me!!! Maria
2009 Aug 26
2
Statistical question about logistic regression simulation
Hi R help list I'm simulating logistic regression data with a specified odds ratio (beta) and have a problem/unexpected behaviour that occurs. The datasets includes a lognormal exposure and diseased and healthy subjects. Here is my loop: ors <- vector() for(i in 1:200){ # First, I create a vector with a lognormally distributed exposure: n <- 10000 # number of study subjects
2010 Jan 13
2
Simulation numbers from a probability table
Dear friends, If I have a table like this, first row A B C D ... are different levels of the variable, first column 0 1 2 4 ... are the levels of the "numbers", the numbers inside the table are the probabilities of the "number" occuring. A B C D ... 0 0.2 0.3 0.1 0.05 1 0.1 0.1 0.2 0.2 2 0.02 0.2 0 0.1 4 0.3 0.01 0.01
2004 Dec 09
1
How can I estimate parameters of probability distributions?
Hi list, I have a group of data. It looks like they follow a exponential distribution. In R, how can I esimate lamda, that is the rate in pexp, of the distribution and can I use Kolmogorov-Smirnov for hypothesis testing in such a situation? I have read the "8.2 Examing the distribution of a set of data" of "An Introduction to R" but I did not find any clues on this issue.
2003 Oct 06
1
visualizing transition probability matrices
Dear List, I have a couple of (~200) 3x3 transition probability matrices (ie each defines a Markov chain). They are all estimated from the same underlying process, so it ie meaningful to take their elemetwise mean and standard deviation. [1] First question: supposing that they are given in a list l, how do I get their elementwise mean and standard deviation? Fortunately, the mean of trans. prob.
2012 Jan 27
3
generate a random number with rexp ?
dear list I use runif to generate a ramdom number between min and max runif(n, min=0, max=1) however , the syntaxe of rexp does not allow that rexp(n, rate = 1) and it generate a number with the corresponding rate. The question is: how to generate a number between min and max using rexp(). Regards -- PhD candidate in Computer Science Address 3 avenue lamine, cité ezzahra, Sousse 4000
2023 Apr 08
1
Error message for infinite probability parameters in rbinom() and rmultinom()
Dear all, Using rmultinom() in a stochastic model, I found this function returns an error message 'NA in probability' for an infinite probability. Maybe, a more precise message will be helpful when debugging. > rmultinom(1, 3:5, c(1/2, 1/3, Inf)) Error in rmultinom(1, 3:5, c(1/2, 1/3, Inf)) : NA in probability vector > rmultinom(1, 3:5, c(1/2, 1/3, NA)) Error in rmultinom(1,
2023 Apr 08
1
Error message for infinite probability parameters in rbinom() and rmultinom()
>>>>> Christophe Dutang >>>>> on Sat, 8 Apr 2023 14:21:53 +0200 writes: > Dear all, > Using rmultinom() in a stochastic model, I found this function returns an error message 'NA in probability' for an infinite probability. > Maybe, a more precise message will be helpful when debugging. >> rmultinom(1, 3:5, c(1/2, 1/3,
2023 Apr 08
1
Error message for infinite probability parameters in rbinom() and rmultinom()
On 08/04/2023 5:53 p.m., Martin Maechler wrote: >>>>>> Christophe Dutang >>>>>> on Sat, 8 Apr 2023 14:21:53 +0200 writes: > > > Dear all, > > > Using rmultinom() in a stochastic model, I found this function returns an error message 'NA in probability' for an infinite probability. > > > Maybe, a more
2003 Jul 18
2
Probability plotting with R
Hello, Our professor asked us to do probability plotting using weibull paper, exponential paper, normal, log-normal paper, etc. I know I can create Q-Q plot for normal dist. and see if all te points are on one line. How do I go about other distributions? I tried generating different samples and use the general qq function. However, I could not do it since I don't know the population
2010 Mar 24
2
Monte Carlo simulation in R
Hi, R-helpers, I'm trying to use R to do a Monte Carlo simulation and need the help. What I have is a matrix that consists of the probabilities for the persons to choose zones. For example, in the matrix shown below, each column represents a person, and each row represents a zone. So, the probability that the first person will choose the 2nd zone is 30%. 25% 30% 10% 30% 20% 0% 20% 50% 60%
2010 Mar 24
1
with data in the form of an R data objecte: Monte Carlo simulation in R
Hi, please use the following the matrix z as the example: x<-c(2,4,5,7,6,9,8,2,0) y<-matrix(x,3,3) z<-apply(y,2,function(x)x/sum(x)) z On Tue, Mar 23, 2010 at 6:59 PM, David Winsemius <dwinsemius@comcast.net>wrote: > > On Mar 23, 2010, at 9:05 PM, Hongwei Dong wrote: > > Hi, R-helpers, >> >> I'm trying to use R to do a Monte Carlo simulation and
2010 Nov 09
1
Question related to combination and the corresponding probability
Dear r users, I have 4 variables x1,x2,x3,x4 and each one has two levels, for example Y and N. For x1: prob(Y)=0.6, prob(N)=0.4; For x2: prob(Y)=0.5, prob(N)=0.5; For x3: prob(Y)=0.8, prob(N)=0.2; For x4: prob(Y)=0.9, prob(N)=0.1; Therefore, the sample space for (x1, x2, x3, x4)={YYYY, YYYN, YYNY,......} (16 possible combination) and the corresponding probabilities are {(0.6)(0.5)(0.8)(0.9),
2017 Jun 01
0
Latin Hypercube Sampling when parameters are defined according to specific probability distributions
I think you should take this conversation private or seek local statistical expertise. This is about strategies for analysis, not about programming in R. Cheers, Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Wed, May 31, 2017 at