similar to: Constructing a lm for predict() by hand

Hello, I'm trying to plot a fitted lm() line on a plot when the one explanatory variable is log transformed and log="x". I get different lines using abline and predict.lm(). #Example x <- 1:100 y <- rnorm(100) plot(y ~ x, log="x") abline(lm(y ~ log(x))) lines(x, predict(lm(y ~ log(x))), lwd=2) I'm sure I'm missing something but could someone tell me which

summary(x), where x is the output of lm, produces the expectedd display, including standard errors of the coefficients. summary(x)$coefficients produces a vector (x is r$individual[[2]]): > r$individual[[2]]$coefficients tX(Intercept) tXcigspmkr tXpeld tXsmkpreve mn -2.449188e+04 -4.143249e+00 4.707007e+04 -3.112334e+01 1.671106e-01 mncigspmkr mnpeld

Suppose you fit a linear model > model.1 ~ lm(v1 ~ ..., data=myframe) and v2 is some other column of myframe typically not in the model. You will often want to try > plot(v2, model.1$residuals) but this will fail if there are NAs in the response v1 as model.1$residuals has length equal to the number of nonmissing values in v1. I suppose > plot(v2[!is.na(v1)],

Greetings, I'd be grateful if a good Samaritan helps me to approach this problem.... with my data, I've created the following model lm(formula = OUTCOME ~ VAR1 + VAR2) summary(model) Call: lm(formula = OUTCOME ~ VAR1 + VAR2) Residuals: Min 1Q Median 3Q Max -1.4341 -0.3621 0.1879 0.4994 0.7696 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 1.89020

Three different external hard drives (Seagate, Western Digital and noname USB 3.0 enclosure) refused to be recognized as the umass devices. Reverting /usr/src/sys/dev/bsd/controller to r248085, building and loading just xhci module makes drives appear again. Below are snippets from the log in both cases: Non working: Jul 4 14:35:17 twinhead kernel: xhci0: <XHCI (generic) USB 3.0

I have a new system which includes a Plextor PX-740a DVD+-R/RW CD-R/RW drive attached to an Asus A8V-MX motherboard. When I try to use burncd to burn a cd, it writes all of the data, says "fixating CD, please wait.." and then reports burncd: ioctl(CDRIOCFIXATE): Input/output error Oddly enough, the CD seems to be usable. I can successfully burn the same file if I use cdrecord. The

Just for fun (and actually because I would use it too) I wrote a version of the "paste" menu command that assumes the clipboard contains a transcript, and just pastes the commands from it into the R console window (Windows GUI only). So, if something like this: > foo <- + 33 > foo * 3 [1] 99 > foo [1] 33 is on the clipboard, then the "paste commands" menu

My new PC has an internal 16-in-1 card reader connected via USB 2.0. The device is the Techsolo TCR-1640 (http://www.techsolo.de/product/cardreader/tcr_1640/index.php). I boot from a compact flash inserted in it and I can mount and unmount the same CF once the system has booted and has mounted the root partition from my graid3 array. The problem arise when I replace the inserted CF with another

Hi everyone I've been playing with do.call() but I'm having problems understanding it. I have a list of "n" elements, each one of which is "d" dimensional [actually an n-by-n-by ... by-n array]. Neither n nor d is known in advance. I want to bind the elements together in a higher-dimensional array. Toy example follows with d=n=3. f <-

I was trying to create a function with a value computed at creation time, using substitute(), but I got results I don't understand: > this.is.R Error: Object "this.is.R" not found > substitute(this.is.R <- function() X, list(X=!is.null(options("CRAN")[[1]]))) this.is.R <- function() TRUE > # the above expression as printed is what I want for the

Consider the following example: # substitute a with b in the indicated function. Seems to work. > z <- substitute( function()a+1, list(a=quote(b)) ) > z function() b + 1 # z is an object of class call so use eval # to turn it into an object of class expression; however, # when z is evaluated, the variable a returns. > eval(z) function()a+1 Why did a suddenly reappear again

Does anyone have something like tapply that is extremely fast for matrices when there is a very large number of levels of the grouping variable? I'm referring to, for example, tapply(x, grouping.variable, function.operating.on.submatrix) where x is a matrix and the submatrix is a subset of the rows of x. The grouping variable's length equals the number of rows of x. -- Frank E

Hi R masters, Sorry for first mensage, this is orignal text... y<-c(2.8150,3.5239,4.0980,4.5845,5.0709,5.4824,5.8427,6.3214,6.7349,7.3651) x<-c(37,42,47,52,57,62,67,72,77,82) I need fit R and A in y=f(x)=R*exp(A*x), with minimize sd= sqrt(SRR/(n-2)) where SRR is Sum of the Square of the Residuals and n is number of data points (in this case 10) How do I make this? Thanks in advance

I'm trying to create a language structure that is a call to a function with a number of arguments that is only known at run time. I do this by using repeated indices to expand out a call with a single argument. However, when I change one of the arguments, all are changed. I don't see the same behavior when I initially create a call with multiple arguments. Even more strangely,

Hi, I need to read in some files. The file names contain come meta characters such as @, #, and white spaces etc, In read.csv, file= option, is there any way that one can make the function to recognize a file path with those characters? Thanks Johnny [[alternative HTML version deleted]]

Potential bug: I mistyped weights in the call ('weigths') and it did not produce any error= message. The coefs were exactly the same like without weights, so I was su= spicious and when weights(nls1) gave NULL, I saw my typo. Usually the function will say "Unused arguments", which shows you the error= , but not nls. Regards Stephen [[alternative HTML version deleted]]

Hi Folks, I've facing an intermittent hang with a USB port which seems cam related: Event's that happen are: o USB modem (HUAWEI E220) plugged into PC ugen3.2: <HUA WEI> at usbus3 u3g0: <3G Modem> on usbus3 u3g0: Found 3 ports. umass0: <USB MASS STORAGE> on usbus3 umass0: SCSI over Bulk-Only; quirks = 0x0000 umass0:6:0:-1: Attached to scbus6 umass1: <USB

Thank you for the reference to Knuth. Indeed in vol. 2 he has a > -----Original Message----- > From: Tony Plate [mailto:tplate@blackmesacapital.com] > Sent: Friday, September 24, 2004 8:05 AM > To: Vadim Ogranovich > Subject: Re: [Rd] algorithm reference for sample() > > Have you tried looking in Knuth's books on computer > algorithms? (They are classics for good

There are some interesting comments re Paul Murrell's new book, R, & SAS on Andrew Gelman's blog: http://www.stat.columbia.edu/~cook/movabletype/archives/2005/04/a_new_book_on_r.html -- Tony Plate

Tony Plate <tplate <at> acm.org> writes: > > Since the virtue and reliability of Wikis was brought up, I created a R > Wiki page for this at > http://www.sciviews.org/_rgui/wiki/doku.php?id=beginners:surprises:emptysetfuncs > > > Anyone: please correct errors and improve it! > > Tony Plate > OK, now I have another question: I see a wiki at