similar to: Confidence Interval

Displaying 20 results from an estimated 2000 matches similar to: "Confidence Interval"

2007 Sep 26
3
Scientific Notation
Dear List: Below is how I specify an axis: axis(2, at=c(0.00005, 0.0005)) R displays the numbers in scientific notation. What argument/parameter should I use to tell R to display the numbers as specified rather than in scientific notation? > version _ platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status major
2008 Nov 25
2
Heat Maps
Dear List, Does there exist a function that produces a heat map like this one (image 3 of 4): http://www.tdameritrade.com/tradingtools/options360.html?a=HDY&referrer=http%3A%2F%2Fquery.nytimes.com%2Fsearch%2Fsitesearch%3Fquery%3Dheatmaptype%3Dnyt In addition to colors, two other main features I am intersted in are: 1. Proportionality in the size of the grid. 2. Mose-over capability. I may
2007 Sep 07
1
How to obtain parameters of a mixture model of two lognormal distributions
Dear List, I have read that a lognormal mixture model having a pdf of the form f(x)=w1*f1(x)+(1-w1)*f2(x) fits most data sets quite well, where f1 and f2 are lognormal distributions. Any pointers on how to create a function that would produce the 5 parameters of f(x) would be greatly appreciated. > version _ platform i386-pc-mingw32 arch i386 os
2009 May 09
2
Histogram frequencies with a normal pdf curve overlay
Dear List, When I plot a histogram with 'freq=FALSE' and overlay the histogram with a normal pdf curve, everything looks as expected, as follows: x <- rnorm(1000) hist(x, freq=FALSE) curve(dnorm(x), add=TRUE, col="blue") What do I need to do if I want to show the frequencies (freq=TRUE) with the same normal pdf overlay, so that the plot would still look the same? Regards,
2007 Jul 23
3
Aggregate daily data into weekly sums
Dear Lest, I have a two-variable data frame as follows (the time peirod of the actual data set is 10 years): Date Amount 1 6/1/2007 1 2 6/1/2007 1 3 6/4/2007 2 4 6/5/2007 2 5 6/11/2007 3 6 6/12/2007 3 7 6/12/2007 3 8 6/13/2007 3 9 6/13/2007 3 10 6/18/2007 4 11 6/18/2007 4 12 6/25/2007 5 13 6/28/2007 5
2007 Sep 26
2
Password-protect script files
Dear List, Is there any way to password-protect script files (either within R or otherwise)? platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status major 2 minor 5.1 year 2007 month 06 day 27 svn rev 42083 language R version.string R version 2.5.1 (2007-06-27)
2007 May 04
2
Alternatives to unlist()
Given the following, one of the things I am trying to see is what % of draws are below a certain number: lambda <- 3 rate <- 5 n <- 5 set.seed(123) v <- replicate(n, rexp(rpois(1,lambda), rate)) vv <- unlist(v) cat("% of draws below 0.1:", round(length(subset(vv, vv < 0.1))/length(vv)*100,0), "%\n") In actuality, my lambda, rate, and n are 26, 10, 1000000,
2007 May 31
1
R keeps crashing when executing 'rlogspline'
Dear List, I have a simple model as follows: x <- rnorm(500) library(logspline) fit <- logspline(x) n <- 1000000 y <- replicate(n, sum(rlogspline(rpois(1,10), fit))) # last line The problem I keep getting is R crashes when doing the last line. It seems to be fine if n is small, but not if n is 1000000. The message I keep getting is: "R for Windows GUI front-end has
2002 Jun 12
1
confidence intervals
Hello, I wonder if anyone has a function for calculating confidence intervals for ratios. I have mortality rates calculated for several groups from sample data -- but these can be treated as ratios?). I am entertaining the idea of bootstrapping them. Any help would be greatly appreciated. TIA, Marwan ---------------------------------------------------------------------------- ------------
2005 Jan 07
3
lognorm
Hi! I 've a problem to have a lognorm distribution with mean=1 and var (or sigma)=1. rlnorm(1000,0,0) rlnorm(1000,1,1) rlnorm(1000,0,1) .... ? Can you help me?
2012 Sep 01
2
help on setting boundaries for generating random numbers
Dear All,   is there a way to set low and high limits to a simulation with rlnorm()?   as an example:  a <-rlnorm(500,0.7,1)     I get the summary of   Min. 1st Qu. Median Mean 3rd Qu. Max. 0.1175 1.0590 2.1270 3.4870 4.0260 45.3800 I would like to set limits so that the simulated values minimum would be greater then 0.5 and maximum of less than 30. If during simulation a
2004 May 01
2
Generating Lognormal Random variables (PR#6843)
Full_Name: Anthony Gichangi Version: 1.90 OS: Windows XP Pro Submission from: (NULL) (130.225.131.206) The function rlnorm generates negative values for lognormal distribution. x- rlnorm(1000, meanlog = 0.6931472, sdlog = 1) Regards Anthony
2008 May 04
1
Is my understanding of rlnorm correct?
rlnorm takes two 'shaping' parameters: meanlog and sdlog. meanlog would appear from the documentation to be the log of the mean. eg if the desired mean is 1 then meanlog=0. So to generate random values that fit a lognormal distribution I would do this: rlnorm(N , meanlog = log(mean) , sdlog = log(sd)) But when I check the mean I don't get it when sdlog>0. Interestingly I
2013 May 10
1
rlnorm(n, meanlog = 0, sdlog = 1)
Hi list, Does anyone know the code behind rlnorm(n, meanlog = 0, sdlog = 1)? I am going to write it in c#. thanks Alireza [[alternative HTML version deleted]]
2010 Jun 21
2
How to predict the mean and variance of the dependent variable after regression
Hi, folks, As seen in the following codes: x1=rlnorm(10) x2=rlnorm(10,mean=2) y=rlnorm(10,mean=10)### Fake dataset linmod=lm(log(y)~log(x1)+log(x2)) After the regression, I would like to know the mean of y. Since log(y) is normal and y is lognormal, I need to know the mean and variance of log(y) first. I tried mean (y) and mean(linmod), but either one is what I want. Any tips? Thanks in
2009 Feb 11
3
Generating Numbers With Certain Distribution in R
Dear all, Is there a way to generate K numbers of integer (K = 10^6). The maximum value of the integer is 200,000 and minimum is 1. And the occurrences of this integer follows a lognormal distribution. - Gundala Viswanath Jakarta - Indonesia
2008 Feb 20
3
reshaping data frame
Dear all, I'm having a few problems trying to reshape a data frame. I tried with reshape{stats} and melt{reshape} but I was missing something. Any help is very welcome. Please find details below: ################################# # data in its original shape: indiv <- rep(c("A","B"),c(10,10)) level.1 <- rpois(20, lambda=3) covar.1 <- rlnorm(20, 3, 1) level.2
2005 Jun 29
2
MLE with optim
Hello, I tried to fit a lognormal distribution by using optim. But sadly the output seems to be incorrect. Who can tell me where the "bug" is? test = rlnorm(100,5,3) logL = function(parm, x,...) -sum(log(dlnorm(x,parm,...))) start = list(meanlog=5, sdlog=3) optim(start,logL,x=test)$par Carsten. [[alternative HTML version deleted]]
2009 Jul 20
3
Histograms on a log scale
Dear All, I would like to be able to plot histograms/densities on a semi-log or log-log scale. I found several suggestions online http://tolstoy.newcastle.edu.au/R/help/05/09/12044.html https://stat.ethz.ch/pipermail/r-help/2002-June/022295.html http://www.harding.edu/fmccown/R/#histograms Now, consider the code snippet taken from http://www.harding.edu/fmccown/R/#histograms # Get a random
2012 May 16
3
finding mean and SD for a log-normal distribution
Dear R Expert   allow me to ask a quick qestion: I have a mean value of 6 and a SD of 3 describing my distribution. I would like to "convert" this distribution into a log normal distribution that would best describe it when resimulated using log normal distribution. Currently I am using another software to estimate the respective mean and SD on the log scale and the results are: 1.6667