search for: porport

Hi all, I'd like to fit a multivariate regression with the variance of the error term porportional to the predictors, like the WLS in the univariate case. y_1~x_1+x_2 y_2~x_1+x_2 var(y_1)=x_1*sigma_1^2 var(y_2)=x_2*sigma_2^2 cov(y_1,y_2)=sqrt(x_1*x_2)*sigma_12^2 How can I specify this in R? Is there a corresponding function to the univariate specification lm(y~x,weights=x)?? Tha...

...t; in each leaf or stem or step of the tree which is meant to be interpreded as "at this step/stage there are 12 people of this category and 2 of the other. Instead I am presently getting something like .342524 which I guess could be the result of divideing the two groups inorder to find some porportion but im not sure, and would that be 34% group a or group b? I was also wondering how you know which side is the side of each test where the individual passes or fails? Is yes/pass always on the left? I'm pretty sure this is just a mater of changing some sort of default settings and is in no...

Hi, I have a dataset that has 2 groups of samples. For each sample, then response measured is the number of success (no.success) obatined with the number of trials (no.trials). So a porportion of success (prpop.success) can be computed as no.success/no.trials. Now the objective is to test if there is a statistical significant difference in the proportion of success between the 2 groups of samples (say n1=20, n2=30). I can think of 2 ways to do the test: 1. regular t test based on...

Dear All, A few weeks ago I posted a question to this list but unfortunately got no answer! A friend warned me of my english. Again, the problem is: A 2-level 5-factors completely randomized design was used to investigate the potential effects of those factors on a solution's characters (several response variables). Each response-variable was measured repeatedly (13 times) during a