[R] a question about subsetting

Hi all, I started using R about 3 weeks ago, and now I've pretty much figured out how to do the types of statistical modeling, graphs, tables etc. that I frequently   use (with zero background in computer languages or other statistical packages that are similar to R like S or SAS!). So it's been

[R] reading data into R

Hi I am really new using R, so this is really a beginner stuff! I created a very small data set on excel and then converted it to .csv file. I am able to open the data on R using the command "read.table ("mydata1.csv", sep=",", header=T)" and it just works fine. But when I want to work on the d

[R] anovas ss typeI vs typeIII

Hi all, I have been struggling with ANOVAs on R. I am new to R, so I created a simple data frame, and I do some analyses on R just to learn R and then check them on SPSS to make sure that I am doing fine. Here is the problem that I've run into: when we use the aov function, it uses SS Type I as

[R] a question about "by" and "ddply"

Hi all, I have a data set (df, n=10 for the sake of simplicity here) where I have two continuous variables (age and weight) and I also have a grouping variable (group, with two levels). I want to run correlations for each group separately (kind of similar to "split file" in SPSS). I've been expe