similar to: linear trend line and a quadratic trend line.

I'd like to use linear and quadratic trend analysis in order to find out a change in slope. Basically, I need to solve a similar problem as discussed in http://www.gseis.ucla.edu/courses/ed230bc1/cnotes4/trend1.html My subjects have counted dots: one dot, two dots, etc. up to 9 dots. The reaction time increases with increasing dots. The theory is that 1 up to 3 or 4 points can be counted

-----Original Message----- Message: 6 Date: Mon, 20 Jan 2003 01:11:24 +0100 From: Martin Michlmayr <tbm at cyrius.com> To: r-help at stat.math.ethz.ch Subject: [R] quadratic trends and changes in slopes I'd like to use linear and quadratic trend analysis in order to find out a change in slope. Basically, I need to solve a similar problem as discussed in

Hi All, I am a newcomer to R. Could anyone explain me how to define link functions for either mu/sigma to allow for quadratic trends in the same, when fitting non-stationary GEV distributions? Thanks -- View this message in context: http://www.nabble.com/QUADRATIC-TREND-FOR-LINK-FUNCTIONS-ON-NON-STATIONARY-GEV-tp23360751p23360751.html Sent from the R help mailing list archive at Nabble.com.

Dear all, I'm performing RDA on plant presence/absence data, constrained by geographical locations. I'd like to constrain the RDA by the "extended matrix of geographical coordinates" -ie the matrix of geographical coordinates completed by adding all terms of a cubic trend surface regression- . This is the command I use (package vegan): >rda(Helling ~

Dear R list members, I'm encountering a problem with expand.model.frame(): Suppose that I define the following simple function (meant just to illustrate the problem): > fun <- function(model){ + expand.model.frame(model, all.vars(formula(model))) + } > and I have the following model, created with an explicit data argument: > mod Call:

Dear R-devel list members, I'd like to suggest a more flexible procedure for generating contrast names. I apologise for a relatively long message -- I want my proposal to be clear. I've never liked the current approach. For example, the names generated by contr.treatment paste factor to level names with no separation between the two; contr.sum simply numbers contrasts (I recall an

Hello Rui, Thanks for your helpful suggestions. Just for illustration, let's use the well known Duncan dataset of prestige vs education + income that is contained in the "car" package. Suppose I wish to use boot function to bootstrap a linear regression of prestige ~ education + income and use the following script: duncan.function <- function(data, indices) {data =

I am getting an error message from scatterplot: > library(car) > scatterplot(Prestige$income~Prestige$type) Error in Summary.factor(c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, : range not meaningful for factors In addition: Warning message: In Ops.factor(x[floor(d)], x[ceiling(d)]) : + not meaningful for factors > The command does output the kind of graph that I want (boxplots).

I got a set of data which has seasonal trend in form of sinx, cosx, I don't have any idea on how to deal with it. Can you give me a starting point? Thanks, Terry

Hello, Much clearer now, thanks. It's a matter of changing the function boot calls to return the predicted values at the point of interess, education = 50, income = 75. I have changed the way the function uses the indices a bit, the result is the same, it's just the way I usually do it. pred.duncan.function <- function(data, indices) { mod <- lm(prestige ~ education +

R 2.2.0 windows XP How can I perform a regression analyses using a vector of means, a variance-covariance matrix? I looked at the help screen for lm and did not see any option for using the afore mentioned structures as input to lm. Thanks, John John Sorkin M.D., Ph.D. Chief, Biostatistics and Informatics Baltimore VA Medical Center GRECC, University of Maryland School of Medicine Claude D.

I noticed that when I fit a linear model using 'lm' there is an attribute called "factors" that is added to the "term". It doesn't seem to appear for 'model.matrix', just 'lm'. I have been unable to find where it gets constructed or what it means? It looks like a two dimensional array that I may be able to use so I would just like to get some

Dear List, I don't get scatter3d to color the sheres according to the '|' argument. library(car) scatter3d(prestige ~ income + education|type, data=Prestige) The spheres on my screen are all colored the same and they are not conditional on Prestige$type. On the other hand: Fit3d and Ellipse3d are colored according to the group argument. rgl_0.92.879 car_2.0-12 R version 2.15.0

R-help is not a free coding service. We expect users to make the effort to learn R and *may* provide help when they get stuck. Pay a local R programmer if you do not wish to make such an effort. Cheers, Bert On Oct 14, 2017 7:58 AM, "Janh Anni" <annijanh at gmail.com> wrote: Greetings! We are trying to obtain confidence and prediction intervals for a predicted Y value from

Greetings all! Got another question for you: When doing regression, is there a way of automatically obtaining the standardized correlation coefficients? /Fredrik -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the

Greetings! We are trying to obtain confidence and prediction intervals for a predicted Y value from bootstrapped linear regression using the boot function. Does anyone know how to code it? Greatly appreciated. Janh [[alternative HTML version deleted]]

Hi In the following, the graph I see on the screen and the .png output coincide. However, in the .pdf file, the fonts seem to be scaled fairly larger, resulting in the label for the top legend disappearing. Is this an infelicity or bug, or is there something I've missed? More generally, how do I control the size of fonts used in legends and axis labels? library(car) library(ggplot2) qp

Dear all, I'm trying to use "scatterplot" from package "car" to get a scatterplot with row-names as labels and I want my data to be divided into two groups defined by the column "tresh". Leaving away the groups-command gives me the right labels but they are not distinguished by colors according to "tresh". Does anybody know why the following example

I am wont to decode a speex 11kbps 8kHz 16bit to a raw data 8kHz 16bit LSB on a c5509. Trying to understand the "testenc-TI-C5x.c" exsample, but it looks to me wary complicated. Is there more documentation for the exsample or a decoder exsample available? Can somebody help? Peter -------------- next part -------------- An HTML attachment was scrubbed... URL:

Buenas tardes   Estoy intentando representar graficamente la elipse de confianza de dos pendiente en un modelo sin intercepto La formula que introduzo esplot(ellipse(recta,c(1,1)),type="l"), pero elipse me sale una recta   Gracias [[alternative HTML version deleted]]