similar to: Simulating data and imputation

Displaying 20 results from an estimated 400 matches similar to: "Simulating data and imputation"

2011 Feb 07
1
multiple imputation manually
Hi, I want to impute the missing values in my data set multiple times, and then combine the results (like multiple imputation, but manually) to get a mean of the parameter(s) from the multiple imputations. Does anyone know how to do this? I have the following script: y1 <- rnorm(20,0,3) y2 <- rnorm(20,3,3) y3 <- rnorm(20,3,3) y4 <- rnorm(20,6,3) y <- c(y1,y2,y3,y4) x1 <-
2010 Oct 29
1
Simulating data, loop
Hello, I would like to run a script in which a loop is included. Since I'm new to R, I cannot manage the following problem. I really hope someone could help me out. Data in the variable Y should be removed from the simulated data set with probability 0.50 if the variable X has a value below zero, and with probability 0.10 if X has a value above zero (see script). However, the total number of
2005 Apr 04
1
custom loss function + nonlinear models
Hi all; I'm trying to fit a reparameterization of the assymptotic regression model as that shown in Ratkowsky (1990) page 96. Y~y1+(((y2-y1)*(1-((y2-y3)/(y3-y1))^(2*(X-x1)/(x2-x1))))/(1-((y2-y3)/(y3-y1))^2)) where y1,y2,y3 are expected-values for X=x1, X=x2, and X=average(x1,x2), respectively. I tried first with Statistica v7 by LS and Gauss-Newton algorithm without success (no
2004 Jun 17
1
Votre question a Amazon.fr
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2009 Feb 25
3
indexing model names for AICc table
hi folks, I'm trying to build a table that contains information about a series of General Linear Models in order to calculate Akaike weights and other measures to compare all models in the series. i have an issue with indexing models and extracting the information (loglikehood, AIC's, etc.) that I need to compile them into the table. Below is some sample code that illustrates my
2003 Jul 27
1
multiple imputation with fit.mult.impute in Hmisc
I have always avoided missing data by keeping my distance from the real world. But I have a student who is doing a study of real patients. We're trying to test regression models using multiple imputation. We did the following (roughly): f <- aregImpute(~ [list of 32 variables, separated by + signs], n.impute=20, defaultLinear=T, data=t1) # I read that 20 is better than the default of
2008 Nov 26
1
multiple imputation with fit.mult.impute in Hmisc - how to replace NA with imputed value?
I am doing multiple imputation with Hmisc, and can't figure out how to replace the NA values with the imputed values. Here's a general ourline of the process: > set.seed(23) > library("mice") > library("Hmisc") > library("Design") > d <- read.table("DailyDataRaw_01.txt",header=T) > length(d);length(d[,1]) [1] 43 [1] 2666
2009 Apr 04
0
multiple imputation
Hi, I'm relatively new to R and it'll be great if someone can help me with what I'm doing here. I am trying to do multiple imputation on my dataset, but I'm not quite sure which function to use as my dataset contains dichotomous variables. Here's an outline of what i've done so far, and i'm not sure if i'm doing it right, and where to go from here. It'll be
2007 Jul 17
0
Multiple imputation with plausible values already in the data
Hello, this is not really an R-related question, but since the posting guide does not forbid asking non-R questions (even encourages it to some degree), I though I'd give it a try. I am currently doing some secondary analyses of the PISA (http://pisa.oecd.org) student data. I would like to treat missing values properly, that is using multiple imputation (with the mix package). But I am not
2011 Oct 18
1
getting basic descriptive stats off multiple imputation data
Hi, all, I'm running multiple imputation to handle missing data and I'm running into a problem. I can generate the MI data sets in both amelia and the mi package (they look fine), but I can't figure out how to get pooled results. The examples from the mi package, zelig, etc., all seem to go right to something like a regression, though all I want are the mean and SE for all the
2012 Mar 07
0
Multiple imputation using mice
Dear all, I am trying to impute data for a range of variables in my data set, of which unfortunately most variables have missing values, and some have quite a few. So I set up the predictor matrix to exclude certain variables (setting the relevant elements to zero) and then I run the imputation. This works fine if I use predictive mean matching for the continous variables in the data set. When I
2011 Jul 20
1
Calculating mean from wit mice (multiple imputation)
Hi all, How can I calculate the mean from several imputed data sets with the package mice? I know you can estimate regression parameters with, for example, lm and subsequently pool those parameters to get a point estimate using functions included in mice. But if I want to calculate the mean value of a variable over my multiple imputed data sets with fit <- with(data=imp, expr=mean(y)) and
2011 Oct 11
1
Mean or mode imputation fro missing values
Dear R experts, I have a large database made up of mixed data types (numeric, character, factor, ordinal factor) with missing values, and I am looking for a package that would help me impute the missing values using ?either the mean if numerical or the mode if character/factor. I maybe could use replace like this: df$var[is.na(df$var)] <- mean(df$var, na.rm = TRUE) And go through all the many
2003 Jun 16
1
Hmisc multiple imputation functions
Dear all; I am trying to use HMISC imputation function to perform multiple imputations on my data and I keep on getting errors for the code given in the help files. When using "aregImpute" the error is; >f <- aregImpute(~y + x1 + x2 + x3, n.impute=100) Loading required package: acepack Iteration:1 Error in .Fortran("wclosepw", as.double(w), as.double(x),
2006 Sep 27
1
Any hot-deck imputation packages?
Hi I found on google that there is an implementation of hot-deck imputation in SAS: http://ideas.repec.org/c/boc/bocode/s366901.html Is there anything similar in R? Many Thanks Eleni Rapsomaniki
2007 Sep 24
0
longitudinal imputation with PAN
Hello all, I am working on a longitudinal study of children in the UK and trying the PAN package for imputation of missing data, since it fulfils the critical criteria of taking into account individual subject trend over time as well as population trend over time. In order to validate the procedure I have started by deleting some known values ?we have 6 annual measures of height on 300 children
2011 Mar 28
0
imputation
Hello! I have some problem with package rminer function imputation. For example, i have data frame > data.frame(X1,X2,X3) X1 X2 X3 1 2002 82 88.53316 2 2001 39 68.41058 3 NA NA NA but when i use imputation, R gives an error > print(imputation("hotdeck",d, "X3")) Error in DTS[, YDTS] = 0 : incorrect number of subscripts on matrix Coud you
1999 Apr 03
0
Joe Shafer's imputation packages
Joe Schafer has some imputation libraries in S plus, and one of them is even on stand alone for Windows. Has anybody attempted to write these very useful packages in R? Jose Ramon Albert Manila, Philippines -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info",
2018 Feb 07
0
Error when running duplicate scale imputation for multilevel data
Hi, I am working with a multiple-item questionnaire. I have previously done item-level multiple imputation using MICE in R and right now I am attempting duplicate-scale imputation based on the guidelines listed in Enders's applied missing data analysis book. I use MICE to do MI as it allows me to specify school effect as I am working with multilevel data; my respondents come from different
2018 May 23
0
MICE passive imputation formula
Hi all, I have a question about multiple imputation within the MICE package. I want to use passive imputation for my variable called X, because it is calculated out of multiple variables, namely Y, Z. Let's give an example with BMI. I know, that if I want to use passive imputation for BMI, I can use the following command: meth["BMI"] <- "~I(weight/(height/100)^2)"