similar to: trend test for frequencies

Displaying 20 results from an estimated 1000 matches similar to: "trend test for frequencies"

2006 Apr 01
1
Nested error structure in nonlinear model
I am trying to fit a nonlinear regression model to data. There are several predictor variables and 8 parameters. I will write the model as Y ~ Yhat(theta1,...,theta8) OK, I can do this using nls() - but "only just" as there are not as many observations as might be desired. Now the problem is that we have a factor "Site" and I want to include a corresponding error
2010 Apr 13
2
Generating model formulas for all k-way terms
For the vcdExtra package, I'm exploring methods to generate and fit collections of glm models, and handling lists of such model objects, of class "glmlist". The simplest example is fitting all k-way models, from k=0 (null model) to the model with the highest-order interaction. I'm having trouble writing a function, Kway (below) to do what is done in the example below >
2013 Nov 25
4
lmer specification for random effects: contradictory reults
Hi All, I was wondering if someone could help me to solve this issue with lmer. In order to understand the best mixed effects model to fit my data, I compared the following options according to the procedures specified in many papers (i.e. Baayen <http://www.google.it/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CDsQFjAA
2007 Jan 17
1
Coefficient of determination when intercept is zero
I am curious as to the "lm" calculation of R2 (multiple coefficient of determination, I assume) when intercept is zero. I have 18 data points, two independent variables: First, a model with an intercept: > mod0=lm(Div~Rain+Evap,data=test) > summary(mod0)$r.squared [1] 0.6257541 > cor(predict(mod0),test$Div)^2 [1] 0.6257541 The $r.squared and the result from "cor"
2007 Dec 24
1
curve fitting problem
I'm trying to fit a function y=k*l^(m*x) to some data points, with reasonable starting value estimates (I think). I keep getting "singular matrix 'a' in solve". This is the code: ox <- c(-600,-300,-200,1,100,200) ir <- c(1,2.5,4,9,14,20) model <- nls(ir ~ k*l^(m*ox),start=list(k=10,l=3,m=0.004),algorithm="plinear") summary(model) plot(ox,ir) testox <-
2012 Jan 10
1
importing S3 methods with importFrom
In my own package, I want to use the default S3 method of the generic function lrtest() from the lmtest package. Since I need only one function from lmtest, I tried to use importFrom in my NAMESPACE: importFrom(lmtest, lrtest) However, this fails R CMD check in the examples: Error in UseMethod("lrtest") : no applicable method for 'lrtest' applied to an object of class
2011 Jan 06
4
Different LLRs on multinomial logit models in R and SPSS
Hello, after calculating a multinomial logit regression on my data, I compared the output to an output retrieved with SPSS 18 (Mac). The coefficients appear to be the same, but the logLik (and therefore fit) values differ widely. Why? The regression in R: set.seed(1234) df <- data.frame( "y"=factor(sample(LETTERS[1:3], 143, repl=T, prob=c(4, 1, 10))), "a"=sample(1:5,
2006 Jan 10
2
Obtaining the adjusted r-square given the regression coefficients
Hi people, I want to obtain the adjusted r-square given a set of coefficients (without the intercept), and I don't know if there is a function that does it. Exist???????????????? I know that if you make a linear regression, you enter the dataset and have in "summary" the adjusted r-square. But this is calculated using the coefficients that R obtained,and I want other coefficients
2010 Sep 08
4
coxph and ordinal variables?
Dear R-help members, Apologies - I am posting on behalf of a colleague, who is a little puzzled as STATA and R seem to be yielding different survival estimates for the same dataset when treating a variable as ordinal. Ordered() is used to represent an ordinal variable) I understand that R's coxph (by default) uses the Efron approximation, whereas STATA uses (by default) the Breslow. but we
2009 Aug 13
2
glm.nb versus glm estimation of theta.
Hello, I have a question regarding estimation of the dispersion parameter (theta) for generalized linear models with the negative binomial error structure. As I understand, there are two main methods to fit glm's using the nb error structure in R: glm.nb() or glm() with the negative.binomial(theta) family. Both functions are implemented through the MASS library. Fitting the model using these
2013 Sep 12
6
declaring package dependencies
I received the following email note re: the vcdExtra package > A vcd update has shown that packages TIMP and vcdExtra are not > declaring their dependence on colorspace/MASS: see > > http://cran.r-project.org/web/checks/check_results_vcdExtra.html But, I can't see what to do to avoid this, nor understand what has changed in R devel. Sure enough, CRAN now reports errors in
2011 Aug 17
2
dotchart vs. dotplot ... groups
I'm trying to create a dotplot with some grouping. I've been able to create what I want using dotchart (basic graphics), but can't quite get it using dotplot (lattice). I prefer to use lattice (or ggplot2) because I think it's a bit easier to control some other aspects of the plot appearance. Basically, w/ lattice I've not been able to get the y-axis label to include the
2008 Jan 26
1
Read stata file from internet?
Dear R-helpers, I would like to have my students read into R an online Stata dataset: 'http://www.stat.ucla.edu/projects/datasets/risk_project.dta' I was able to read it into R after downloading it and converting it with StatTransfer (http://www.stattransfer.com/). Here is what happens when I use read.dta() as I would use read.table(): > require(foreign) > risk2 <-
2017 Jun 29
0
Different date formats in one column
I doubt your actual file looks like the mess that made it to my email software (below) because you posted HTML-format email. Read the Posting Guide, and in particular figure out how to send plain text email. You might try the "anytime" contributed package, though I suspect it too will choke on your mess. Otherwise, that will pretty much leave only a brute-force series of regular
2005 Jun 06
3
write.dta limits
Hope everyone id doing great .. Just need some clarification over the limit of write.dta. I have some coauthors that use stata and I need to send them my data in .dta format. the data.frame is 41706x229 and I get the following Error in write.dta(Panel, file = "STATADATA/Panel.dta", version = 7) : a binary write error occured Once I subset the data everything works out fine. my
2017 Jun 28
4
Different date formats in one column
Hi,? I have a data set with various date formats in one column and not sure how to unify it.Here is a few formats: 02091702/22/170221201703/17/160015-08-239/2/1500170806May-2-201522-March-2014 I tried parse_date_time from lubridate library but it failed.Thanks so much.?Best,Farnoosh [[alternative HTML version deleted]]
2018 Mar 22
3
exporting data to stata
Hi, I am new to R and I want to export data into Stata. Could somebody help with that? Thanks a lot. This is the code I am using: > setwd("D:/datasets/Seg-bcn/ESBD") > data1 <- readRDS("r17045_ESDB_Habitatges_BDD_V_1_0.rds") > library(foreign) > write.dta(data="data1", file = "D:/datasets/data1.dta") Error in write.dta(data =
2008 Aug 06
3
Help in running Stata dataset in R
Dear All, I installed R 2.7.0 and tried to call a dataset i had ealier own called on R2.6.2 but i keep on getting an error: use("maltreat.dta") Error in fromchar(x) : character string is not in a standard unambiguous format Tried doing the same with R2.7.1 but i get the same error. However if i call the same on R 2.6.2, there is no error: use("maltreat.dta") > des()
2011 Aug 06
3
.dta from e-mail
I got a .dta extension file by e-mail, but I can't save it in my computer and open it in R. How can I do it? [[alternative HTML version deleted]]
2017 Jun 29
1
Different date formats in one column
Thanks Jeff. This is a nice way of solving this problem. What about the cases with 0015-02-21?Many thanks.?Best,Farnoosh On Wednesday, June 28, 2017 10:49 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote: I doubt your actual file looks like the mess that made it to my email software (below) because you posted HTML-format email. Read the Posting Guide, and in particular