[R] Doing pairwise comparisons using either Duncan, Tukey or LSD

Hi, I have a basic and simple question on how to code pairwise (multiple) mean compariosn between levels of a factor using one of the Duncan, Tukey or LSD. Thanks in advance, Saeed -- View this message in context: http://www.nabble.com/Doing-pairwise-comparisons-using-either-Duncan%2C-Tukey-

[R] An error in fitting a non linear regression

h in the plot depth is drawn on Y axis but in the regression model "depth" in independent. Plot shows the real world of what happne to the crop root growth. Thank you. Saeed Ahmadi -- View this message in context: http://www.nabble.com/An-error-in-fitting-a-non

Re: [R] An error in fitting a non linear regression

Hi, Thank you for the reply and suggestions. I have two questions? 1) If I want to use log, it seems that I have to take log from both sides of the model which will lead to lm(log(q)~log(-depth)). What is tehdifference between this syntax and lm(log(q) ~ I(-depth))? 2) How can I calculate the R

[R] Syntax in taking log to transfrom the data to fit Gaussian distribution

Hi, I have a data set (weight) that does not follow the Gaussian (Normal) distribution. However, I have to transform the data before applying the Gaussian distribution. I used this syntax and used log(weight) as: posJy.model<-glm(log(weight) ~ factor(pos), family=gaussian(link='identity'), subset

Re: [R] An error in fitting a non linear regression

Hi Peter, You are totally right and it was a miscalculating and misunderstanding from me. Regarding the R-squared calculation of non linear model (question 2), is there any way to do that? Regards Saeed Petr Pikal wrote: > > Hi > > r-help-boun...@r-project.org napsal dne 24.02.2009 11:31:22:

Re: [R] Syntax in taking log to transfrom the data to fit Gaussian distribution

(straight line fitted to the data). Saeed Philipp Pagel-5 wrote: > > On Tue, Feb 24, 2009 at 02:46:07AM -0800, Saeed Ahmadi wrote: >> I have a data set (weight) that does not follow the Gaussian (Normal) >> distribution. However, I have to transform the data before applying the >&g

[R] Finding Lambda in Poisson distribution

Hi, I have a dataset. First of all, I know that my dataset shall follow the Poission distribution. Now I have two questions: 1) How can I check that my data follow the Poisson distribution? 2) How can I calculate Lambda of my data? Regards Saeed -- View this message in context: http://www.nabb