search for: linearhypothesi

Displaying 20 results from an estimated 21 matches for "linearhypothesi".

Did you mean: linearhypothesis
2012 Jul 09
1
linearHypothesis and factors
...his. I'm running a regression, say: reg <- lm(Y ~ x1 + year) where x1 is a continuous variable and year is a factor with various year levels. Individually, each year factor variable is not significant, but I have a suspicion they are jointly significant. I can't figure out how to run a linearHypothesis test with a factor, i.e. linearHypothesis(reg, ??? year=0 ??? , vcov=vcovHC(reg, , "HC1")) Would be very much appreciated. Many thanks, Alex -- View this message in context: http://r.789695.n4.nabble.com/linearHypothesis-and-factors-tp4635814.html Sent from the R help mailing list ar...
2012 Oct 09
1
car::linearHypothesis Sum of Sqaures Error?
...ture),c("I vs. X&M","X vs. M")) contrasts(env$Moisture)<-Transect_moisture_contrasts > contrasts(env3l$Moisture) I vs. X&M X vs. M X -1 1 I 2 0 M -1 -1 soilmodel<-lm(MSOIL~Forest+Burn*Thin*Moisture+ROCK,data=env3l) > linearHypothesis(soilmodel,"MoistureI vs. X&M") Linear hypothesis test Hypothesis: MoistureI vs. X&M = 0 Model 1: restricted model Model 2: MSOIL ~ Forest + Burn * Thin * Moisture + ROCK Res.Df RSS Df Sum of Sq F Pr(>F) 1 22 9.4106 2 21 8.8272 1 0.58333 1.3877 0.252 &g...
2012 Jan 31
0
Error in linearHypothesis.mlm: The error SSP matrix is apparently of deficient rank
...HFe p[HF] p[HF]<.05 2 Factor 0.8480886 0.5258849 0.9795716 0.5408084 > ezANOVA(data, dv = .(Measure.1), wid = .(Participant), within = .(Factor), + type = 3, detailed = T) Note: model has only an intercept; equivalent type-III tests substituted. Error in linearHypothesis.mlm(mod, hyp.matrix, SSPE = SSPE, idata = idata, : The error SSP matrix is apparently of deficient rank = 4 < 5 Error in ezANOVA_main(data = data, dv = dv, wid = wid, within = within, : The car::Anova() function used to compute results and assumption tests seems to have failed. Most com...
2012 May 29
2
setting parameters equal in lm
...ut setting parameters equal? I have used the car package to set up linear hypotheses: X1 = rnorm(20, 10, 5); X2 = rnorm(20, 10, 5); X3 = rnorm(20, 10, 5) Y = .5*X1 + 3*X2 + .5*X3 + rnorm(20, 0, 15) data.set = data.frame(cbind(X1, X2, X3, Y)) linMod = lm(Y~X1 + X2 + X3, data=data.set) require(car) linearHypothesis(linMod, c("(Intercept)=0", "X1-X3=0")) (forgive the unconventional use of the equal sign....old habit). Unfortunately, the linearHypothesis is always compared to a full model (where the parameters are freely estimated). I want to have an ANOVA summary table for the reduced mod...
2011 Sep 22
1
Wrapper of linearHypothesis (car) for post-hoc of repeated measures ANOVA
...ericity is violated (i.e. leaving aside post-hoc to lme models). The best solution I found was John Fox's proposal to similar requests in R-help: http://tolstoy.newcastle.edu.au/R/e2/help/07/09/26518.html http://tolstoy.newcastle.edu.au/R/e10/help/10/04/1663.html However, I think that using linearHypothesis() is not as straightforward as I would desire for testing specific contrasts between factor levels. The hypotheses must be defined as linear combinations of the model coefficients (subject to response transformations according to the intra-subjects design), which may need some involved calculation...
2010 Aug 27
1
calculate the elasticities by linear.hypothesi commander
Dear all If I run the model and get the estimated parameter a11. Then I want to use the estimated parameter to calculate the elasticities by using the formula e11=a11/mw1-1. What I have done is using the command of linear. Hypothesis. > formulas1=dWfresh~dlnPfresh+dlnPfrozen+dlnPsmoke+dlnQP+cosL1+sinL1+cosL2 >
2012 Feb 08
2
dropterm in MANOVA for MLM objects
Dear R fans, I have got a difficult sounding problem. For fitting a linear model using continuous response and then for re-fitting the model after excluding every single variable, the following functions can be used. library(MASS) model = lm(perf ~ syct + mmin + mmax + cach + chmin + chmax, data = cpus) dropterm(model, test = "F") But I am not sure whether any similar functions is
2011 Mar 20
3
manova question
Dear friends, Sorry for this somewhat generically titled posting but I had a question with using contrasts in a manova context. So here is my question: Suppose I am interested in doing inference on \beta in the case of the model given by: Y = X %*% \beta + e where Y is a n x p matrix of observations, X is a n x m design matrix, \beta is m x p matrix of parameters, and e is a
2013 May 01
2
significantly different from one (not zero) using lm
Hello, I am work with a linear regression model: y=ax+b with the function of lm. y= observed migration distance of butterflies x= predicted migration distance of butterflies Usually the result will show if the linear term a is significantly different from zero based on the p-value. Now I would like to test if the linear term is significantly different from one. (because I want to know
2015 Jun 26
1
[R-pkg-devel] Guidelines for S3 regression models
...re applicable. An overview which lists some (but not all) useful methods is in Table 1 of vignette("betareg", package = "betareg"). For coef() and vcov() it is useful/important that the names and dimension match. Then Wald tests can be easily computed in functions like car::linearHypothesis(), car::deltaMethod(), lmtest::waldtest(), or lmtest::coeftest(). Thanks & best wishes, Achim > http://www.milbo.org/doc/modguide.pdf > > Your comments would be appreciated. > > Stephen Milborrow > > ______________________________________________ > R-package-devel at...
2012 Jul 21
2
car::Anova - Can it be used for ANCOVA with repeated-measures factors.
...t with the other factors), but when calling Anova on the model, I don't know how I can specify the between-within design (i.e., which parts of the model should interact with the repeated measures factors). As far as I understand it, neither the idesign, icontrasts or imatrix arguments, nor the linearHypothesis function can specify the within-between design (as far as I get it they all specify the within or intra-subject design, see John Fox's slides from User 2011: http://web.warwick.ac.uk/statsdept/useR-2011/TalkSlides/Contributed/17Aug_1705_FocusV_4-Multivariate_1-Fox.pdf). If this it is not poss...
2010 Nov 06
2
3-way interaction simple slopes
Can anyone show me how to test for significant simple slopes of a 3-way interaction, with covariates. my equation tmod<-(glm(PCL~ rank.f + gender.f + MONTHS + CEXPOSE.M + bf.m + MONTHS*CEXPOSE.M*bf.m, data=mhatv, family=gaussian ,na.action=na.omit)) Thank you Mike [[alternative HTML version deleted]]
2011 Oct 18
1
contrasts in MANOVA
Dear r-helpers, I have a query regarding use of contrasts in MANOVA. summary(manova(model)) gives me only result of test for overall difference. Would you be so kind and give me a hint how to get the same test statistics (e.g.Pillai's) and P values for the predefined contrasts? Best regards Ondrej Mikula -- Institute of Animal Physiology and Genetics Academy of Sciences of the Czech
2015 Feb 16
0
Release of phia 0.2-0
...s of multiple comparisons of factor contrasts, and is specially suited for the analysis of interaction effects. The function "testFactors" provides a flexible user interface for defining combinations of factor levels and covariates, to evaluate and test the model, using the function "linearHypothesis" from package "car". "testInteractions" gives a simpler interface to test multiple comparisons of simple effects, interaction residuals, interaction contrasts, or user-defined contrasts. "interactionMeans" may be used to explore the "cell means" of fact...
2015 Feb 16
0
Release of phia 0.2-0
...s of multiple comparisons of factor contrasts, and is specially suited for the analysis of interaction effects. The function "testFactors" provides a flexible user interface for defining combinations of factor levels and covariates, to evaluate and test the model, using the function "linearHypothesis" from package "car". "testInteractions" gives a simpler interface to test multiple comparisons of simple effects, interaction residuals, interaction contrasts, or user-defined contrasts. "interactionMeans" may be used to explore the "cell means" of fact...
2013 Nov 16
1
repeated-measures multiple regression/ANCOVA/MANCOVA
Dear List, I am trying to analyze a dataset where I have 1 continuous between-item variable (C), and 2 factorial within-item variables (3- and 2-level: F3, F2). I'm interested in whether slope of C is different from 0 at different combinations of F3 and F2, and whether it varies between these combinations. And unfortunately I need a decent anova-like table with p-values. The reason is that
2009 Jun 16
1
Output of Anova (CAR package) in Sweave
Dear list, I use Sweave almost exclusively for writing papers, and I have become quite spoiled by the excellent xtable export facilities. Has anybody written an xtable method for the Anova function in CAR, or has anybody used a different set of functions to import Anova results into a table in an Sweave document? If not, any handy hints on how to write a good homebrew based on the output of Anova
2012 Oct 30
4
Error unary operator
Hi R - listers, I am receiving an error. Does anyone know what this means? J ggplot(subset(foo, Rayos != "Rayos.NA"), aes(x=HTL, y=DevelopIndex, colour=TotalEggs)) +geom_point() +geom_jitter() + facet_grid(Aeventexhumed ~ Rayos) + geom_smooth(method="lm", fill=NA) + ylim(c(0, 7)) Error in +geom_smooth(method = "lm", fill = NA) : invalid argument to unary
2012 Dec 05
1
Using multcomp::glht() with Anova object
Hello everyone, I've conducted a Type III repeated-measures ANOVA using Anova() from the car package, based on the suggestions at http://blog.gribblelab.org/2009/03/09/repeated-measures-anova-using-r/(option 3) and http://languagescience.umd.edu/wiki/EEG#ERP_ANOVA_in_R. My ANOVA has two factors: Condition (3 levels) and Region (6 levels) and their interaction. Below is code to run the Anova
2011 Nov 24
3
How to deal with package conflicts
In my genridge package, I define a function ridge() for ridge regression, creating objects of class 'ridge' that I intend to enhance. In a documentation example, I want to use some functions from the car package. However, that package requires survival, which also includes a ridge() function, for coxph models. So, once I require(car) my ridge() function is masked, which means I have to