similar to: R: x-y data

Hello I followed the example in page 59, chapter 11 of the 'Introduction to R' manual. I entered my own x,y data. I used the least squares. My function has 5 parameters: p[1], p[2], p[3], p[4], p[5]. I plotted the x-y data. Then I used lines(spline(xfit,yfit)) to overlay best curves on the data while changing the parameters. My question is how do I calculate the residual sum of squares.

I am trying to fit a curve to a cumulative mortality curve (logistic) where y is the cumulative proportion of mortalities, and t is the time in hours (see below). Asym. at 0 and 1 > y [1] 0.00000000 0.04853859 0.08303777 0.15201970 0.40995074 0.46444992 0.62862069 0.95885057 1.00000000 [10] 1.00000000 1.00000000 > t [1] 0 13 20 24 37 42 48 61 72 86 90 I tried to find starting values for

I want to extra the part of the formula not including the response variable from an lm object. For example if the lm object ABx.lm was created by the call ABx.lm <- lm( y ~ A + B + x, ...) Then ACx.lm is saved as part of a workspace. I wish to extract "~ A + B + x". Later in my code I will fit another linear model of the form z ~ A + B + x for some other response variable z. I

Hello all, So I am using the (formula entry) method for randomForests: randomForest(y~x1+x2+...+x39+x40,data=xxx,...) but the issue is that some of the items in that package dont take a formula entry - you have to explicitly state the y and x vector: randomForest(x=xxx[,c('x1','x2',...,'x40')],y=xxx[,'y'],...) Now my question is whether there is a function/way

Hi All, I have location data set up as degrees: minutes: seconds (for example, 122:45:45) I need to get this data into decimal degree form (eg, 122.7625). I know that I need to use the formula: Decimal degrees = Degrees + (Minutes/60) + (Seconds/3600) Does anyone know how I can get R to do this? The original data is all in one column (called 'lat') and the degrees, mins and secs

A common process when data is obtained in an Excel spreadsheet is to save the spreadsheet as a .csv file then read it into R. Experienced users might have learned to be wary of dates (as I have) but possibly have not experienced what just happened to me. I thought I might just share it with r-help as a cautionary tale. I received an Excel file giving patient details. Each patient had an ID

Hi, I want to run t.test() for several variables among two groups, and I would like to skip the tedious process of collecting information to assemble a table, but I am not sure if the function I want already exists. Any suggestion would be appreciated. I have a working example, as required by the posting guide: my_swiss = swiss[-1,] my_swiss$facto = rep(1:2,nrow(my_swiss)/2)

I am trying to figure out why 'biglm' can handle large data set... According to the R document - "biglm creates a linear model object that uses only p^2 memory for p variables. It can be updated with more data using update. This allows linear regression on data sets larger than memory." After reading the source code below? I still could not figure out how 'update'

I have been using internal snapshots on production qcow2 images for a couple of years, admittedly as infrequently as possible with one exception and that exception has had multiple snapshots taken and removed using virt-manager's GUI. I was unaware of this: > There are some technical downsides to > internal snapshots IIUC, such as inability to free the space used by the > internal

There is a bug in `predict' whereby the order of variables sometimes gets re-arranged compared to the original fit, and then disaster results. Specifically, the 'variables' and 'predvars' attributes of a 'terms' object get out of synch. This only happens when the terms in the original formula get re-ordered during fitting: test> scrunge.data_ data.frame(

Hi all, I've got a problem with the nls function. I have an adjustment which works when I fix one of the argument of my function (Xo=150) : *Xo*=150 f<- function (tt*,Xo*,a,b) ifelse(tt<*Xo*,a*exp(-b**Xo*),a*exp(-b*tt)) ajust<-nls(RER~f(tt,*Xo*,a,b),data=data.frame(tt=Ph2[,2*k],RER=Ph2[,2*k+1]),start=list(a=0.5,b=0.014)) But, when I use it as a "normal" parameter (and

# R for Windows will not send your bug report automatically. # Please copy the bug report (after finishing it) to # your favorite email program and send it to # # r-bugs at r-project.org # ###################################################### This report is joint from Richard Heiberger <rmh at temple.edu> and Burt Holland <bholland at temple.edu>. Burt Holland is the coauthor

Dear R-Help, With the attached data set, I am still getting incorrect bwplots > xyplot(gdf$tt~gdf$OnHour |gdf$Runway, data=gdf) # Is correct > bwplot(gdf$tt~gdf$OnHour |gdf$Runway, data=gdf, horizontal=FALSE) # Puts the boxes on the wrong x-axis values # look especially at 0 and 3. How do I fix this? What is happening? Thanks, Jim Rome

Dear R-users, I would need some advices on the proper way to call a particular function. This function is called scope.char and it is embedded in the step.gam function from the gam package. I am trying to call scope.char directly in a script but I did not find the proper way to do so. Is this even possible? If so, what is the proper syntax? Thank you for your time and help. Sebastien

Dear all, I would like to suggest changing the pairs.formula command such that a command like pairs(GNP ~ . - Year - GNP.deflator, longley) would behave in a similar fashion as lm(GNP ~ . - Year - GNP.deflator, longley) i.e., make a pairwise scatterplot of GNP and all other variables in the (longley) dataframe except for Year and GNP.deflator. The above command, with the

Hello, I am having hard time obtaining a value from a function. "fit" is a survival function that produces some results, such as "median", "confidence intervals" etc. But str() function does not list these values. How can I extract these to be able use them? For example, I need "median" value for the group DrugA which is 48. "Print" function does

Dear list, i am a biologist who needs to do some ttest between disease and non disease, sex, genotype and the serum levels of proteins on a large number of individuals. i have been using excel for a long time but it is very tedious and time consuming. i am posting the data below and ask your help in generating a code to get this analysis done in R. thanks gender disease genotype data M N CC

The survival package makes significant use of the "specials" argument of terms(), before calling model.frame; it is part of nearly every modeling function. The reason is that strata argments simply have to be handled differently than other things on the right hand side. Likewise for tt() and cluster(), though those are much less frequent. I now get "bug reports" from the

The following code should give me (at least that's what I think) two list boxes with their individual scrollbars. But instead both scrollbars stick to the same listbox even though they work as they should (scroll individual listboxes). When I remove all the widgets on top everything works perfectly. Any help would be highly apprecciated. ps: all subsequent listboxes and scrollbars work

Hi to all, I have some problems to get the times-scale to the x-axis the times are coming from an excel sheet f. e [1] "0:01:00" "0:02:00" "0:03:00" "0:04:00" "0:05:00" "0:06:00" "0:07:00" [8] "0:08:00" "0:09:00" "0:10:00" "0:11:00" "0:12:00" "0:13:00"