similar to: Getting Pr from Summary(lm)

Hello, I have a small statistics question, and as I'm quite new to statistics and R, I'm not sure if I'm doing things correctly. I am looking at two quantitative variables (x,y) that are correlated. When I divide the data set according to a categorical variable z, then x and y are more poorly correlated when z = A than when z = B (see attached figure). In fact x and y are two

Hello, I've had no luck finding an R package that has the ability to estimate a Tobit model allowing for heteroskedasticity (multiplicative, for example). Am I missing something in survReg? Is there another package that I'm unaware of? Is there an add-on package that will test for heteroskedasticity? Thanks for your help. Cheers, Alan Spearot -- Alan Spearot Department of Economics

Hello, I would like to inlude the Q-Q plot by "qqmath" into a panel with other plots, say, using par(mfrow=c(1,2)). How can this be done given that "qqmath" refreshes the plotting window and there seems to be no series coming out of it? Thanks Serguei [[alternative HTML version deleted]]

Hi, I'm trying to aggregate date values using the aggregate function. For example: aggregate(data,by=list(weekdays(LM),months(LM)),FUN=length) I would also like to aggregate by year but there seems to be no years() function. Should there be one? Is there any alternative choice? Also, a hours() function would be great. Any tip on this? Thanks in advance! S?rgio Nunes

Hi there, I'm writing a function that calculates the probability of different outcomes of dice rolls (e.g., the sum of the highest three rolls of five six-sided dice). I'm using the "combinations" function from the "gtools" package, which is great: it gives me a matrix with all of the possible combinations (with repetitions allowed). Now I want to count the number

Hi everyone, I'm interested in the analysis of spatial data, and I'm trying out several R-packages. Today I was attempting to use the package vardiag (version 0.1): >> library(vardiag) >> rs4.vo <- varobj(rs4[,2:4],trace=2) >[1] 1 >Error: couldn't find function "nlregb" so far I know "nlregb" is a S-plus function for optimization, so this

Hi out there, I am trying to fit a species accumulation curve (increase in number of species known vs. sampling effort) for multiple regions and several bootstrap samples. The bootstrap samples represent different arrangements of the actual sample sequence. I fitted a series of nlme-models and everything seems OK, but since the observations are correlated I tried to include some correlation

I have an interesting lme - problem. The data is part of the Master Thesis of my friend, and she had some problems analysing this data, until one of her Jurors proposed to use linear mixed-effect models. I'm trying to help her since she has no experience with R. I'm very used to R but have very few experience with lme. The group calls of one species of parrot were recorded at many

Hi! Can anyone tell me how to convert the anova/ancova summary output into a data frame? Thanks! Shane Phillips [[alternative HTML version deleted]]

library(effects) mod <- lm(Measurement ~ Age + Sex, data=d) e <-effect("Sex",mod) The effect is evaluated at the mean age. > e Sex effect Sex F M 43.33083 44.48531 > > e$model.matrix (Intercept) Age SexM 1 1 130.5859 0 23 1 130.5859 1 To evaluate the effect at Age=120 I tried: e

Hello, I am trying to get the same values for the adjusted means and standard errors using R that are given in SAS for the following data. The model is Measurement ~ Age + Gender + Group. I can get the adusted means at the mean age by using predict. I do not know how to get the appropriate standard errors at the adjusted means for Gender using values from predict. So I attempted to get them

I am using the following model: lm <- lm(mydata[[variableName]] ~ Age + Gender + Group, data=mydata) There are 5 groups in "Group": nonc (the control), c1,c2,c3 and c4. How do I contrast nonc vs the others? and How do I contrast c1 vs other c's (ie c2,c3,c4 as a subgroup)? I have looked at the contrasts option in lm and model.matrix and am really none the wiser. Though it

Hi, I am unable to get the tick marks to appear thicker in plot. I have tried things like par(lw=2) but this only seems to affect other line thicknesses. The use of axes directly fixes the problem because lw = 2 applies to both the axis and the ticks. Is there is way of feeding a single parameter to plot or setting a par parameter to do this? I am using R 1.9.0 on a windows 2000 platform.

Something for the wish list (not really a bug): I was reminded of what I see as a problem with summary.glm last week when some of my students fell into a trap in a homework exercise, defining a logit model in which coefficients were aliased. When this happens in lm, summary.lm prints a message ["Coefficients: (1 not defined because of singularities)"], but summary.glm is silent. In

Hi i have a linux mandrake 7.2 server using cups I am triying to use samba for printig but it is not working this is my smb.conf file ;*******************section global***************** [global] workgroup = KVJ server string = Samba Server %v printcap name = cups load printers = yes printing = cups log file = /var/log/samba/log.%m max log size = 50 security = user socket options = TCP_NODELAY

Hi, folks, I would like to copy the output of summary(lm) and anova (lm) in R to my word file. But the output will be a mess if I just copy after I call summary and anova. ##################### x=rnorm(10) y=rnorm(10,mean=3) lm=lm(y~x) summary(lm) Call: lm(formula = y ~ x) Residuals: Min 1Q Median 3Q Max -1.278567 -0.312017 0.001938 0.297578 1.310113

I have a simple linear model (fitted with lm()) with 2 independant variables : one categorical and one integer. When I run summary.lm() on this model, I get a standard linear regression summary (in which one categorical variable has to be converted into many indicator variables) which looks like : Estimate Std. Error t value Pr(>|t|) (Intercept) -3595.3 2767.1 -1.299

Hola Freddy. Yo parto de un shape en que tengo los típicos archivos .shp, .sbx, .sbn, .shx y .dbf. En la tabla tengo el área de los poligonos en m2, el perímetro, el estado y el código ISO del estado dispuesto por el SGM. ¿Me puedes orientar un poco más? Gracias, Sebastían. El 14 de agosto de 2013 16:19, Freddy Omar López Quintero < freddy.vate01@gmail.com> escribió: > Hola

Hi all, I use the R2HTML package to print results, but I have a little problem when I want to print a table provides from a summary.lm. If I want to align this table differently of the others, I use the "align" argument ("left", "center or "right") of the HTML function , but it prints "Coefficients left" (or "Coefficients center",

dear R experts: I wonder whether it is possible to extend the summary method for the lm function, so that it uses an option "hccm" (well, model "hc0"). In my line of work, it is pretty much required in reporting of almost all linear regressions these days, which means that it would be very nice not to have to manually library car, then sqrt the diagonal, and recompute