[R] batch job GLM calculations

[Indermaur Lukas]

Hello

I want to batch job the calculation of many GLM-models, extract some values and store them in a file. Almost everything in the script below works (read file, extract values and write them to file) except I fail in indexing the GLM with the modelstructure it should run. Running GLM's conventionally is no problem.

 

Conventionally a GLM is calculated as:

--------------------------------------

glm(ZlogHRS ~ ZRi+ZE+ZPROX_MN+ZED+ZAlwd+ZT2+ZW+ZN+Sex+y, family = gaussian, data=t.data) 

(just a note: dependent variable is ZlogHRS, while the others are indepent variables)

 

Desired way: sequentially run GLM

---------------------------------

I want R to take the model structure to take from a vector called "modelstructure" and paste it into the GLM like:

glm(modelstructure[i], family = gaussian, data=t.data).

It would considerably ease my workload if there is a solution to the indexing problem within a GLM. I appreciate any hint.

Best regards

Lukas

p.s.

my R skills are rather poor

 

----------------------------------------START R-CODE-----------------------------------

# Read file

t.url <- "C://HR_calculations/2005_2006/HR_SIZE/Kandidatenmodelle_Berechnung/inputfiles/"

t.tuti <- read.table(paste(t.url, "All_animals.txt", sep=""),header=T)

 

collect.results <- function(x) {

#resets vectors which will be filled

i <- 0

AICA <- NA;

 

#put models names hierarchically in vector

modelnames <- c("1=global", "2=biotic1", "3=biotic2", "4=abiotic") #keep track of changes in model names and number

for (i in 1:length(modelnames)) 

#model structure of the four models given for all models to run

#global

modelstructure <- c(

"ZlogHRS ~ ZRi+ZE+ZPROX_MN+ZED+ZAlwd+ZT2+ZW+ZN+Sex+y",

#biotic1

"ZlogHRS ~ ZRi",

#biotic2

"ZlogHRS ~ ZPROX_MN",

#abiotic

"ZlogHRS ~ ZE")

 

ts.model <- glm(modelstructure[i], family = gaussian, data=t.data) 

 

# Extracts some mode results

n[i] <- length(resid(ts.model))

AICA[i] <- AIC(ts.model)

}

#Writes results to data file

x = data.frame(

modelnames, n, AICA)

write.table(x, paste(t.url, file="Results.txt"), sep="\t", quote=F) 

----------------------------------------END R-CODE-----------------------------------

 

 

 

 
°°° 
Lukas Indermaur, PhD student 
eawag / Swiss Federal Institute of Aquatic Science and Technology 
ECO - Department of Aquatic Ecology
Überlandstrasse 133
CH-8600 Dübendorf
Switzerland
 
Phone: +41 (0) 71 220 38 25
Fax    : +41 (0) 44 823 53 15 
Email: lukas.indermaur at eawag.ch
www.lukasindermaur.ch