similar to: analysis of covariance and constrained parameters

Displaying 20 results from an estimated 200 matches similar to: "analysis of covariance and constrained parameters"

2007 Nov 02
3
writing a categorical var. with condition
Hello, I want to create a new variable which includes 4 age categories in this way: if (age>=12 && age<32) age1==1 if (age>=32 && age<52) age1==2 if (age>=52 && age<72) age1==3 if (age>=72 && age<100) age1==4 but I get the results only for the first observation. how can I apply this condition to all observations? Thanks in advance,
2007 Feb 09
2
LM Model
Dear R-Users, How can I put a pre-defined regression model into to an object of class lm in order to use the predict.lm function. A simplified example: I would normally run a regression analysis on a dataset, > germany<-lm(RENT~AGE1, in.mi01) > summary(germany) Call: lm(formula = RENT ~ AGE1, data = in.mi01) Residuals: Min 1Q Median 3Q Max
2008 Jan 15
2
Looking for simpler solution to probabilistic question
Hi I have two processes which take with a certain probability (p1 and p2) x number of years to complete (age1 and age2). As soon as thge first process is completed, the second one begins. I want to calculate the time it takes for the both processes to be completed. I have the following script which gives me the answer, butI think there must be a more elegant way of doing the calculations
2002 Nov 26
1
Reshape by multiple variables
Dear list I'm using the reshape command and want to reshape a wide data set to a long one e.g. I have the variables y1,y2,y3,age1,age2,age3,sex,ethnic I want my new long data set to consist of the variables y (which has been created from y1,y2,y3), age (which has been created from age1,age2,age3), sex and ethnic I have tried to use the command:
2008 May 12
1
Standard error of combination of parameter estimates
Hi, Is there a simple command for computing the standard error of a combination of parameter estimates in a GLM? For example: riskdata$age1 <- riskdata$age riskdata$age2 <- ifelse(riskdata$age<67,0,riskdata$age-67) model <- glm(death~age1+age2+ldl, data=riskdata,family=binomial(link=logit)) And we want to find the standard error of the partial linear predictor for
2009 Sep 21
2
cox memory
Hi there, I have a rather large data set and perform the following cox model: test1 <- list(tstart,tstop,death1,chemo1,radio1,horm1) out1<-coxph( Surv(tstart,tstop, death1) ~ chemo1+chemo1:log(tstop+1)+horm1+horm1:log(tstop+1)+age1+grade1+grade1:log(tstop+1)+positive1+positive1:log(tstop+1)+size1+size1:log(tstop+1), test1) out1 Up to here everything works fine (with each covariate
2007 Feb 09
1
subset function
Hello R-Users, I have the following problem with the subset function: See the following simple linear model. Here everything works fine: >germany<-lm(RENT~AGE1, in.mi01) However, if a use the same regression equation and only specify a subset, I get an error message: > berlin<-lm(RENT~AGE1, in.mi01, subset=C_X01=="Berlin") Error in lm.fit(x, y, offset
2011 Oct 05
1
calling a variable which in turn calls many more variables
Hi all, I am running regressions with many covariates, most of which remain the same each time (control variables). Instead of writing 30 demographic variables every regression, is there a way I could call them all at once using a variable called, perhaps "demog"? I have tried: > demog <- list(age1, age2, age3) but I get an error when I try to call a list in a regression. I also
2008 Nov 06
3
unlist & dataframes
Dear all, I would like to know whether it is possible to unlist elements and keep the original format of the data. To make it more clear, let me give an exemple: I have a list l of dataframes that I created with apply but which looks like this: x1=data.frame(Name=LETTERS[1:2],Age=1:2) x2=data.frame(Name=LETTERS[3:4],Age=3:4) l=list(x1,x2) l [[1]] Name Age 1 A 1 2 B 2 [[2]] Name
2005 Aug 12
2
coercing created variables into a new data frame using na.omit()
Hi, I am an R newbie and one thing I am having trouble with binding variables that I have created within one data frame into a new data frame when using na.omit(). To illustrate this problem I will give the example I am working on and the approah I have been using:- data.frame1<-filepath.... attach(data.frame1) #create a new variable using a function new.variable<-rep(1,length(weight3))
2008 Jun 05
1
quite complicated case(the repeated data arranage~)
Hi everyone: I have been struggling with this repeated data type for whole afternoon,I sent two emails to server for help,many people kindly responded , hereby thank you so much,but since I dont want to write to much in email,so I divide the problem in parts,so far this seem did not work out very well,so this is my whole problem~ first I have example of data here:
2008 Aug 21
1
Interpreting Logistic Regression
Hi ! This is Madhavi from Mumbai, India. Incidently this is my first post. I am working on Credit Scoring Model and using R, I have run the logistic regression. I have received following Output. I have two questions (a) What is the significance of "family = binomial(link = logit)". Why do I have to mention Binomial? Is it because my dependent variable assumes only two values 0 and 1?
2007 Mar 05
1
Matrix/dataframe indexing
Hi all, I am hoping someone can help me out with this: If I have dataframe of years and ages and the first column and first row are filled with leading values: Df<- age1 age2 age3 Yr1 1 0.4 0.16 Yr2 1.5 0 0 Yr3 0.9 0 0 Yr4 1 0 0 Yr5 1.2 0 0 Yr6 1.4 0 0 Yr7 0.8 0 0 Yr8 0.6 0 0 Yr9 1.1 0 0 Now the rest of the cells need to be filled according to the previous year and age
2012 Jul 31
1
Mediation analysis
Hello all, I apologize for the simplistic question, but I have been having some trouble learning how to do mediation analysis in R. Ideally, I would like to use Preacher's Bootstrapping test for mediation (Preacher & Hayes, 2004). I have attempted to use the mediate package to set this up, using code that looks basically like this: model.m <- lm(data$outcome ~ data$mediator +
2007 May 05
1
importing data
Hello, I need to import a data set. I have never imported data files with R. I have always worked on simulated data. I have looked at R Data Import/Export manual. It is a bit peculiar because my data base is already an R object called "japan". I guess it is not yet a data set, and I don't know how to manipulate variables from it. When I type "japan", here is an extract
2008 Aug 20
1
Understanding output of summary(glm(...))
Simple example of 5 groups of 4 replicates. >set.seed(5) >tmp <- rnorm(20) >gp <- as.factor(rep(1:5,each=4)) >summary(glm(tmp ~ -1 + gp, data=data.frame(tmp, gp)))$coefficients Estimate Std. Error t value Pr(>|t|)gp1 -0.1604613084 0.4899868 -0.3274809061 0.7478301gp2 0.0002487984 0.4899868 0.0005077655 0.9996016gp3 0.0695463698 0.4899868
2003 Dec 17
5
beginner programming question
Hi all, The last e-mails about beginners gave me the courage to post a question; from a beginner's perspective, there are a lot of questions that I'm tempted to ask. But I'm trying to find the answers either in the documentation, either in the about 15 free books I have, either in the help archives (I often found many similar questions posted in the past). Being an (still actual)
2013 Sep 01
0
Question About Markov Models
Dear All, I am a bit struggling with the many packages for Markov models available in R. Apologies for now posting a code snippet, but I am looking for some guidance here. Please consider a set like the one below (which you can get with data<-read.csv('http://dl.dropboxusercontent.com/u/5685598/data_table.csv') ). ID therapy age1 age2 EFS 7308 ormo_lunga 78
2009 Dec 15
1
error when using multcomp and lm
I am trying to use multcomp to do a Tukey posthoc on growth increments among genetic crosstypes. #Fixed effect model m1 <- lm(inc ~ 0 + Age+ Crosstype + Sex, data = Data.age) summary(m1) RESULTS of the model: summary(m1) Call: lm(formula = inc ~ 0 + Age + Crosstype + Sex, data = Data.age) Residuals: Min 1Q Median 3Q Max -0.87180 -0.34002 -0.02702 0.27710 2.17820
2010 Feb 11
1
Rounding multinomial proportions
I present you with a function that solves a problem that has bugged me for many years. I think the problem may be general enough to at least consider adding this function, or a revamped version of it, to the 'stats' package, with the other multinomial functions reside. I'm using R to export data to text files, which are input data for an external model written in C++. Parts of the