similar to: logistic regression and dummy variable coding

Hello, If I have two variables that are factors or characters and I want to create a new variable that is the combination of both what function can I use to accomplish this? Ex. Var1 Var2 SA100055113 19851113 And I want NewVar SA10005511319851113 Thanks in advance. Cameron Guenther, Ph.D. Associate Research Scientist FWC/FWRI, Marine Fisheries Research 100 8th Avenue S.E. St.

Hi there, I have the following plot. The circles and the line do not cross in the main plot. But in the legend, the circle and the line cross. I am wondering if there is a way to make the legend look like the plot without crossing. I looked around but did not find a way to do that. Is it doable? plot(x,x^1.5, pch=1, lty=1, type='b') legend(1,25, legend="hello",pch=1,

Hi, there I'm currently trying to figure out how to keep my "factor" levels for a variable when moving it from one data frame or matrix to another. Example below: vec1<-(rep("10",5)) vec2<-(rep("30",5)) vec3<-(rep("80",5)) vecs<-c(vec1, vec2, vec3) resp<-rnorm(2,15) dat<-as.data.frame(cbind(resp, vecs))

I have a rather large data set (about 30 predictor variables) I need to preform a logistic regression on this data. My response variable is binary. My code looks like this: mylogit <- glm(Enrolled ~ A + B + C + ... + EE, data = data, family = binomial(link="logit")) with A,B,C, ... as my predictor variables. Some categorical, some continuous, some binary. I run the code and get

Dear All, I am trying to reproduce the example that I found online here http://bit.ly/11VG4ha However, when I run my script (pasted at the end of the email), I notice that there is a factor 2 between the values for the coefficients for the categorical variable female calculated by my script and in the online example. Any idea about where this difference comes from? Besides, how can I

Hello, I was hoping for some advice in changing 2 defaults in a logistic regression. 1. It looks like the first category is the reference category? In the following syntax 'where' has 4 levels, how can I make the reference category the third category? model<- glm(cbind(sucesses, failures) ~ where + who + firstep + dxnarrow + age + sex + medyear, family = binomial, data=life.use)

Hello useRs, I have a problem at hand which I'd think is fairly common amongst groups were R is being adopted for Analytics in place of SAS. Users would like to obtain results for logistic regression in R that they have become accustomed to in SAS. Towards this end, I was able to propose the Design package in R which contains many functions to extract the various metrics that SAS reports.

This is an example from chapter 11 of the 6th edition of Devore's engineering statistics text. It happens to be a balanced data set in two factors but the calculations will also work for unbalanced data. I create a factor called 'cell' from the text representation of the Variety level and the Density level using '/' as the separator character. The coefficients for the linear

Dear all, I have a question about the glm. When the events of an observation is 0, the logit function on it is Inf. I wonder how the glm solve it. An example: Treat Events Trials A 0 50 B 7 50 C 10 50 D 15 50 E 17 50 Program: treat <- factor(c("A", "B", "C", "D", "E")) events <- c(0, 7, 10, 15,

Hello everyone, I want to plot a "greater than" symbol (the "_" under ">") on the x-axis in the labels. Is it possible to do it? Thanks. Bingshan [[alternative HTML version deleted]]

Hi everyone, I'm a new R user (if this is a really basic question, please do excuse me...) and I'm having some questions regarding a deciles problem. I have a variable which I need to categorize according to its deciles (X). However, this categorization should be made into another variable (call it NewVar). Ex. for the quartiles case (just for the sake of exposition, since I need

I need to use contr.sum and observe that some levels are not statistically different from the overall mean of zero. What is the proper way of forcing the zero estimate? It seems the column corresponding to that level should become a column of zeros. Is there a way to achieve that without me constructing the design matrix? Thank you. Stephen Bond [[alternative HTML version deleted]]

I am using the following model: lm <- lm(mydata[[variableName]] ~ Age + Gender + Group, data=mydata) There are 5 groups in "Group": nonc (the control), c1,c2,c3 and c4. How do I contrast nonc vs the others? and How do I contrast c1 vs other c's (ie c2,c3,c4 as a subgroup)? I have looked at the contrasts option in lm and model.matrix and am really none the wiser. Though it

I would like to add an extension to the current name of a variable to create a new variable that is its sqrt transform. Each piece of the equation below works independently, but the left side definition fails on run. I also tried creating the variable name first, but ended up with an object that toString() did not fix. Better ideas? Example 1

Hello list, how can I go from CALLINGout to just CALLING ? I've tried : exten => s,n,Set(newVAR=${CUT(CALLINGout,,3)}) or exten => s,n,Set(newVAR=$[CUT(CALLINGout,,3)]) But no result : [Jan 4 11:10:12] -- Executing [s at from-S:34] NoOp("SIP/s2-0000003b", "newVAR=") in new stack Asterisk 1.6.10 here. Kind regards, Jonas. -------------- next part

I need an object created in a user defined function to be accessible to another user defined function. I am fairly certain the object is correctly created as it prints when I use the return() function, however the 2nd function seems unable to use it. I am guessing objects created in functions are not globally accessible, is this correct? What is an appropriate way to pass the object to the

HI there, i know this is a basic question, though i need some help because this is somewhat away from my current issue, but nevertheless interesting to me... Lets assume i have some estimated probabilities, say estimated by a logit model. i know i can also state them as an odds ratio. Now i?d like to state these odds ratios as a reference to a specific outcome of my investigated

Dear list, I'm having second thoughts after solving a very trivial problem: I want to extend the relevel() function to reorder an arbitrary number of levels of a factor in one go. I could not find a trivial way of using the code obtained by getS3method("relevel","factor"). Instead, I thought of solving the problem in a recursive manner (possibly after reading

Can anyone help me with the necessary code to relevel a numeric*factor interaction term in a linear model? I would like to report the estimate, std. error and t-value for the reference factor. First, I estimated a linear model with dummy variables and was able to retrieve model estimates for the reference factor using relevel. for example: > summary(update(mod.mod, . ~ . - dummy + +

Hi all, I have a vector and want to merge its elements one by one into a single string or number. For example, x=c(1,2,3), what I want is a new number 123. I used "paste" but it just output "1" "2" "3" which is not what I want. Is there any way to do this? Thanks!