search for: tau

Displaying 20 results from an estimated 170 matches for "tau".

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2007 Aug 07
0
Goodman-Kruskal tau
On Wed, 1 Aug 2007, Upasna Sharma <upasna at iitb.ac.in> wrote: > From: "Upasna Sharma" <upasna at iitb.ac.in> > Subject: [R] Goodman Kruskal''s tau > > I need to know which package in R calculates the Goodman Kruskal''s > tau statistic for nominal data. Also is there any implementation for > multiple classification analysis (Andrews at al 1973) in R? Any > information on this would be greatly appreciated. As far as I kn...
2011 Nov 19
1
wald test: compare quantile regression estimators from different samples
...conditional on a specific characteristic and I would like to test whether such characteristic indeed affect the estimators. The problem in the test anova.rq is that the response variable should be the same, therefore I cannot use different samples. Consider as an example the following: Model 1:Q_y(tau|X,I=2) = X''beta(tau|I=2) Model2;Q_y(tau|X,I=3) = X''beta(tau|I=3) The first sample consider I=2 and the second I=3. I would like to test whether, at the quantile "tau", beta(tau|I=2) = beta(tau|I=3). I have already tried to design a Wald test like: W <- ((beta(tau|I=2)...
2009 Dec 11
2
How to calculte the power of a matrix
Dear R family I have a following question. Suppose I have a matrix as follows, for instance: tau= 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 1 0 0 0 0 I want to calculate (-m) power of tau, for example, m=893. When I run tau^2, the outcome is just tau. Any help would be appreciated. thanks in advance. best moohwan
2007 Feb 22
0
Error in solve.default
...Y, s.e., df.se, corrs, prior, ...) 1: hblm(Diff ~ 1, s = SE) > > hblm function(formula, s.e., df.se = Inf, corrs = F, prior = NULL, fast.calc = F, ...) { # hblm() # main program to create hblm object call <- match.call() call.ab <- abbrev.hblm.call(call) taumin <- (sum(1/s.e.^2))^-0.5 if(is.null(prior$error)) { prior$error$df <- 1 prior$error$sd <- taumin } s.e..old <- s.e. if(max(s.e.) == Inf) s.e.[s.e. == Inf] <- taumin * 10000 wts <<- s.e...
2012 Mar 28
0
Major update: meta version 2.0-0
Version 2.0-0 of meta (an R package for meta-analysis) is now available on CRAN. Changes are described below. Yours, Guido Major revision R package meta linked to R package metafor by Wolfgang Viechtbauer to provide additional statistical methods, e.g. meta-regression and other estimates for tau-squared (REML, ...) New functions: - metareg (meta-regression) - metabias (generic method for function metabias) - metabias.default (generic method for function metabias) - metabias.meta (generic method for function metabias) - metabias.rm5 (ge...
2012 Mar 28
0
Major update: meta version 2.0-0
Version 2.0-0 of meta (an R package for meta-analysis) is now available on CRAN. Changes are described below. Yours, Guido Major revision R package meta linked to R package metafor by Wolfgang Viechtbauer to provide additional statistical methods, e.g. meta-regression and other estimates for tau-squared (REML, ...) New functions: - metareg (meta-regression) - metabias (generic method for function metabias) - metabias.default (generic method for function metabias) - metabias.meta (generic method for function metabias) - metabias.rm5 (ge...
2004 Jul 19
3
why won''t rq draw lines?
I''ve been trying to draw quantile linear regression lines across a scatterplot of my data using attach(forrq) plot(PREGNANT,DAY8,xlab="pregnant EPDS",ylab="postnatal EPDS",cex=.5) taus <- c(.05,.1,.25,.75,.9,.95) xx <- seq(min(PREGNANT),max(PREGNANT),100) for(tau in taus){ f <- coef(rq(DAY8~PREGNANT,tau=tau)) yy <- (f[1]+f[2]*xx) lines(xx,yy) } which is simply the method from the help file with my dataset...
2008 Sep 06
1
Help use try function with boot
...en R is large) thus I try to use "try" to resolve. I put the try function in two cases: case1: put the try in front of the boot > c1.try<-try(boot(c1data, statistic = c1.fun, R=3999),silent=T) > c1.try [1] "Error in nls(formula = density ~ nmf(time, alpha, delta, psi, tau, gamma), : \n Convergence failure: false convergence (8)\n" attr(,"class") [1] "try-error" case2: put the try in front of the nls c1.nmf<-try(nls(density~nmf(time, alpha, delta, psi, tau, gamma), + algorithm="port",data=c1, + lower=c(...
2002 Feb 11
0
profile
...e of the profiling. I''ve been looking at the help page for profile.nls and also I hacked the codes for profile.nls (just by typing profile.nls), but haven''t really found an efficient way to do it. For say, my parameter eta1, I found that the profiler function works between -1.6<tau<1.6. I adjusted the code in profile.nls to profile within that range only (this is a very crude adjustment, see the code below). The new profile works, and I can increase the number of points profiled (by changing delta.t), but for some reason I cannot plot it. I get the following error message:...
2012 Mar 08
1
sas retain statement in R or fitting differene equations in NLS
...are measured. Now, I want to estimate a model which says y= yhat+epsillon as in standard nonlinear regression. Where yhat is the predicted value of y. yhat can be calculated as follows: # This code illustrates how I could simulate the expected values of y if I knew the values of the parameters tau and b. # but in reality I would like to estimate them. # code is for illustration of the principles and is not meant to be functional!! yaux[1]<-0 b<- a_number # b would have to become estimated by nls or nlme tau<- another_number # tau would also be estimated in nls or nlme for (t in 2:1...
2006 Sep 12
1
Kendall''s tau-c
Hello, I can''t find a package which calculates Kendall''s tau-c. There is the package Kendall, but it only calcuates Kendall''s tau-b. Here is the example from ttp://www2.chass.ncsu.edu/garson/pa765/assocordinal.htm. cityriots <- data.frame(citysize=c(1,1,2,2,3,3), riotsize=c(1,2,1,2,1,2), weight=c(4,2,2,3,0,4)) cityriots <...
2006 May 02
1
urppTest Z-tau? Z-alpha?
Hello, Could someone give me a hint about what might be the difference between running urppTest with Z-alpha and Z-tau in type=c("Z-alpha", "Z-tau")? Is this the underlying equation: delta_y(t) = mu + tau*timetrend+(1-rho)*y(t-1) + alpha_1*delta_y(t-1) + ... + alpha_k*delta_y(t-k) + error term ? I looked at Banerjee et al. mentioned in the fSeries documentation, but that didn''t help....
2018 Apr 06
1
Fast tau-estimator line does not appear on the plot
R-experts, I have fitted many different lines. The fast-tau estimator (yellow line) seems strange to me?because this yellow line is not at all in agreement with the other lines (reverse slope, I mean the yellow line has a positive slope and the other ones have negative slope). Is there something wrong in my R code ? Is it because the Y variable is 1 vector...
2009 Jun 09
5
Non-linear regression/Quantile regression
...s, but for my data I need some quadratic function. So I guess, I have to use a nonlinear quantile regression. I tried the example on the help page for nlrq with my data and it worked. But the example there was with a SSlogis model. Trying to write dat.nlrq <- nlrq(BM ~ I(Regen100^2), data=dat, tau=0.25, trace=TRUE) or dat.nlrq <- nlrq(BM ~ poly(Regen100^2), data=dat, tau=0.25, trace=TRUE) (I don''t know the difference) both gave me the following error message: error in getInitial.default(func, data, mCall = as.list(match.call(func, : no ''getInitial'' meth...
2018 Apr 07
1
Fast tau-estimator line does not appear on the plot
...abline( reg1, col = "black" ) reg <- lmrob( Y ~ X ) abline( reg, col = "green" ) Huber <- rlm( Y ~ X ) abline( Huber, col="red" ) Tukey <- rlm( Y ~ X, psi = psi.bisquare ) abline( Tukey, col = "purple" ) L1 <- rq( Y ~ X, tau = 0.5 ) abline( L1, col = "blue" ) fast <- FastTau(model.matrix(~X),Y) fast # save result, then print... avoid computing twice # model matrix leads to first element of beta as constant and # second element of beta as slope abline( fast$beta, col="yellow" )...
2018 Mar 31
2
Fast tau-estimator line does ot appear on the plot
On 31/03/2018 11:57 AM, varin sacha via R-help wrote: > Dear R-experts, > > Here below my reproducible R code. I want to add many straight lines to a plot using "abline" > The last fit (fast Tau-estimator, color yellow) will not appear on the plot. What is going wrong ? > Many thanks for your reply. > It's not quite reproducible: you forgot the line to create Dataset. It's probably something like Dataset <- data.frame(Y, Z) > ########## > > Y=c(2,4,5,4,3,4,...
2011 Sep 27
1
Is there a "latex" summary function in the quantreg package for just 1 tau?
...ar wouldn''t work. I can start opening the functions up, but I am wondering if I had missed some function which is the one I should be using. Here is an example session for a bunch of possible errors: (Thanks) data(stackloss) y <- stack.loss x <- stack.x rq_object <- rq(y ~ x, tau = .5) rq_object_summary <- summary(rq_object) latex(rq_object) # Error in UseMethod("latex") : # no applicable method for ''latex'' applied to an object of class "rq" latex(rq_object_summary) # Error in UseMethod("latex") : # no applicable metho...
2009 Aug 13
1
metafor random effects meta-analysis
Hello, Great to see the new metafor package for meta-analysis. I would like to perform a meta-analysis in which I initially calculate the intercept of the model with a nested random-effects structure. In lme, this would be model<- lme(v3~1, random=~1|species/study, weights = varFixed(~Wt), method = "REML") where multiple effects sizes are measured for some studies and more
2009 Dec 11
1
How could I find the inverse of a matrix?
Dear R family I have a following question. Suppose I have a matrix as follows, for instance: tau= 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 I want to have the inverse of the above matrix and then add some exponent to it. That is, I want to calculate tau to the (-m). For example, m=893. Thanks in advance Best regards Moohwan Kim
2008 May 05
0
kendall tau a,b,c
hi, i have 2 lists of ranks for which i''d like to compute kendall tau. there are ties in the ranks which (to the best of my knowledge) means i cant use tau a but rather b or c. how does R handle that? are ties automatically detected (using corr.test()) and is tau b/c computed instead of tau a? also kendall does not work when values in list 1 do not occur in list...