search for: azamjaafari

Hi   I want to do leave-one-out cross-validation for multinomial logistic regression in R. I did multinomial logistic reg. by package nnet in R. How I do validation? by which function? response variable has 7 levels   please help me   Thanks alot Azam [[alternative HTML version deleted]]

I applied bootpred for multinomial logistic reg. (with nnet package). I used same as theta.fit and theta.predict of R for my data. but give me error. Can I do this with response vriable;7 levels predictor variables:5 (1 classifier, 4 continuous)?   Thanks alot Azam   [[alternative HTML version deleted]]

Dear All   Pleas help me to increase the memory in R.   In order increase memory, I read the FAQ and follow the instruction as below     Close R, then right-click on your R program icon (the icon on your desktop or in your programs directory). Select ``Properties'', and then select the ``Shortcut'' tab. Look for the ``Target'' field and after the closing quotes around the

Dear All   I want to import the vector file (   .shp) to R. I could import the file by rgdal package before, by following:   geology<-readOGR('C:/geology//saga/geo.geom','finalgeology')   but now there is an error:   Error in ogrInfo(dsn = dsn, layer = layer, input_field_name_encoding = input_field_name_encoding) :           GDAL Error 4: .shx file is unreadable, or corrupt.

Hi   I want to draw a plot from observed and predicted data and also shows threshold and data before threshold are identified with different color from data after threshold.   Suppose: abserved data are 0 or 1 predicted data= 0 to 1 threshold=0.5   Thanks alot     [[alternative HTML version deleted]]

Hello all   I have a geology map that has three level, bellow   <-geology lithology    landscape   landform     landform level is used as covariate (with codes=1,2,3,4,5) for training of neural network, but this level has missing data as NA. I want to replace the missing data of landform level with 0 (zero). Finally, landform will have codes  0,1,2,3,4,5.   please help me   Thanks alot.

Hi   I did validation for prediction by logistic regression according to following:   validationsize <- 23 set.seed(1) random<-runif(123) order(random) nrprofilesinsample<-sort(order(random)[1:100]) profilesample <- data[nrprofilesinsample,] profilevalidation <- data[-nrprofilesinsample,] salich<-profilesample$SALIC.H.1 salic.lr<-glm(salich~wetnessindex, profilesample,

Hi   I want to do boosted regression(classification) tree for categorical response (with 7 levels). Can I do this by GBM package?   please help me?   Thanks alot   [[alternative HTML version deleted]]

Dear All   I trained a neural network for 200 data and I did prediction for a grid file (e.g. 1000000 points) such as below:   snn<-predict(nn, newdata=data.frame(wetness=wetnessgrid$band1, ndvi=ndvigrid$band1))   the pixels of snn is same with wetnessgrid or ndvigrid    I want to convert this file (snn) to a map that I can open it in GIS software.     Thanks alot     [[alternative HTML

Hi   I have a problem for saving grid file in R. I want to save a grid file as "tif".   I write this: writeGDAL(predict.grid, 'predict.tif')   after running, I don't recieve any error. But when I want to open the 'file.tif', it doesn't open. for example in paint program: I recieve this: Paint cannot read this file. This is not valid bitmap file, or its format

Hi   I computed probability in each cell. I have:    [99883,] -0.0062412957690  [99884,] -0.0062412957690  [99885,] -0.0062412957690  [99886,] -0.0062412957690  [99887,] -0.0062412957690  [99888,] -0.0062412957690  [99889,]  0.9909126638948  [99890,]  0.9909126638948  [99891,]  0.9909126638948  [99892,]  0.9909126638948  [99893,]  0.9909126638948  [99894,]  0.9909126638948  [99895,] 

Hi list   I want to define a moving window based on ferquency in a grid file. is there a package for this? I found packages for moving window mean, median or quantile.   thanks  [[alternative HTML version deleted]]

Hi   I want to make a grid map using diversity indices. I have a soil grid map with 7 class in r. how can I make a diversity map based on soil map in r?  I found something for calculation diversity in a table (.csv).   Thanks [[alternative HTML version deleted]]

 Hello   I have questions about gbm package.  It seems we have to devide data to two part (training set and test set) for first.   1- trainig set for running of gbm function 2- test set for gbm.perf      is it rigth? I have 123 sample that I devided 100 for trainig and 23 for test.   So, parameter of cv.folds in gbm function is for what?   Thanks alot Azam       [[alternative HTML