Displaying 20 results from an estimated 10000 matches similar to: "Quantile of a function"
2010 Nov 03
3
optim works on command-line but not inside a function
Dear all,
I am trying to optimize a logistic function using optim, inside the
following functions:
#Estimating a and b from thetas and outcomes by ML
IRT.estimate.abFromThetaX <- function(t, X, inits, lw=c(-Inf,-Inf),
up=rep(Inf,2)){
optRes <- optim(inits, method="L-BFGS-B", fn=IRT.llZetaLambdaCorrNan,
gr=IRT.gradZL,
lower=lw, upper=up, t=t, X=X)
2008 Dec 27
1
indexed expression
Hello expeRts,
I need generate symbolize the autocovariances matrix of a Gaussian
ARMA(1,1), for derivate it and evaluate.
I try this codes, but whitout sucess
vacv<-NULL
vacv[1]<-1-2*phi*theta-theta^2
vacv[2]<-(1-phi*theta)*(phi-theta)
vacv[3:n]<-acv[2]*(phi^(1:(n-2)))
facv<-list()
for(i in 1:2)
2010 Aug 18
1
Displaying Results in Two Columns
Could I have some suggestions as to how (various ways) I can display my confidence interval results?
rm(list = ls())
set.seed(1)
func <- function(d,t,beta,lambda,alpha,p.gamma,delta,B){
d <- c(5,1,5,14,3,19,1,1,4,22)
t <- c(94.32,15.72,62.88,125.76,5.24,31.44,1.048,1.048,2.096,10.48)
post <- matrix(0, nrow = 11, ncol = B)
theta <- c(lambda,beta)
beta.hat <- 2.471546
for(j
2012 Jun 07
1
Quantile regression: Discrepencies Between optimizer and rq()
Hello Everyone,
I'm currently learning about quantile regressions. I've been using an
optimizer to compare with the rq() command for quantile regression.
When I run the code, the results show that my coefficients are consistent
with rq(), but the intercept term can vary by a lot.
I don't think my optimizer code is wrong and suspects it has something to do
with the starting
2010 May 17
3
applying quantile to a list using values of another object as probs
Hi r-users,
I have a matrix B and a list of 3x3 matrices (mylist). I want to
calculate the quantiles in the list using each of the value of B as
probabilities.
The codes I wrote are:
B <- matrix (runif(12, 0, 1), 3, 4)
mylist <- lapply(mylist, function(x) {matrix (rnorm(9), 3, 3)})
for (i in 1:length(B))
{
quant <- lapply (mylist, quantile, probs=B[i])
}
But quant
2007 Feb 05
3
Confidence intervals of quantiles
Can anyone please tell me if there is a function to calculate confidence
intervals for the results of the quantile function.
Some of my data is normally distributed but some is also a squewed
distribution or a capped normal distribution. Some of the data sets contain
about 700 values whereas others are smaller with about 100-150 values, so I
would like to see how the confidence intervals change
2008 Sep 23
1
quantile regression: plotting coefficients on only one variable (rq)
Dear all.
I have a question on plotting the coefficients from a series of mutivariate
quantile regressions. The following code plots the coefficients for each
RHS variable x1 and x2. Is there a way to plot only the coefficients on x1?
In the data I am using, I have a large number of fixed effects and do want
to plot the coefficients on these fixed effects.
quant.plot <-
2013 Jun 20
0
how to run copula-based quantile regression
Hi,
I want to run a quantile regression (Y=a+bX+e) using normal and t copula for
my dissertation.
I 've read the documentation of "copula" and "copBasic". However, I still
have difficulty to deal with my data.
Details are as following:
I've already loaded xls data into r using "XLConnect" package.
excel.file<-file.path("Q:/dailyvstoxx.xls")
2010 May 16
1
problems with generation of quantiles under For ()
Dear, I want to make an application to calculate quantile within a For()
I tried the following without success:
ej.
date
p_val <- matrix(sample(10, 1000, replace=TRUE), 200,5)
test 1
rr <- paste("p_val$",names(p_val[1]), sep="")
quant <- quantile(rr, probs = c(0, 10, 20, 30, 40, 50, 60, 70, 80, 90,
100)/100, na.rm=FALSE, type=1)
test 2
rr <-
2012 Sep 09
1
Solving a system of two equations
Hi,
I am trying to find a simple way to numerically solve a system of two
equations equal to zero with two unknowns (x_loc and y_loc). Here is a mock
data set and below it, the equations I need to solve.
theta<-c(180,135,90)/(2*pi)
x<-c(0,0,15)
y<-c(20,0,0)
0 =
-sum((y_loc-y)*(sin(theta)*(x_loc-x)-cos(theta)*(y_loc-y))/(((x_loc-x)^2+(y_loc-y)^2)^0.5)^3)
0 =
2010 Apr 09
2
How to use tapply for quantile
I am trying to calculate quantiles of a data frame column split up by
two factors:
# Calculate the quantiles
quarts = tapply(gdf$tt, list(gdf$Runway, gdf$OnHour), FUN=quantile,
na.rm = TRUE)
This does not work:
> quarts
04L 04R 15R 22L 22R 27 32
33L 33R
0 NULL Numeric,5 NULL Numeric,5 NULL Numeric,5 NULL
Numeric,5 NULL
1 NULL
2006 Sep 30
1
Gradient problem in nlm
Hello everyone!
I am having some trouble supplying the gradient function to nlm in R for
windows version 2.2.1.
What follows are the R-code I use:
fredcs39<-function(a1,b1,b2,x){return(a1+exp(b1+b2*x))}
loglikcs39<-function(theta,len){
value<-sum(mcs39[1:len]*fredcs39(theta[1],theta[2],theta[3],c(8:(7+len))) -
pcs39[1:len] * log(fredcs39(theta[1],theta[2],theta[3],c(8:(7+len)))))
2005 Aug 05
1
contrast {Design} question
All,
I have been trying to get the following code to work:
A.quantiles <- quantile(foo.frame$A,
probs = seq(from = 0.05, to = 0.95, by = 0.05))
base.quantiles <- quantile(Efficacy205$BASELINE_RANK,
probs = seq(from = 0.05, to = 0.95, by = 0.05))
gender <- levels(Efficacy205$GENDER)
contrast.1
<- contrast(Model.1,
list(TPCODE= 'A',
AGE =
2008 Mar 02
3
Need help to locate my mistake
Dear readers
I would like to make General Linear Model (GLM) for the following data set
http://louise.hoffman.googlepages.com/fuel.csv
The code I have written is
fuelData<-read.table('fuel.csv',header=TRUE, sep=',')
n<-dim(fuelData)[1]
xOnes<- matrix(1,nrow=n,ncol=1)
x<-cbind(xOnes,fuelData[,3])
y<-fuelData[,4]
theta<-((t(x)%*%x)^(-1))%*%t(x)%*%y
which gives
2012 Jan 05
2
Bayesian estimate of prevalence with an imperfect test
Hi all!
I'm new to this forum so please excuse me if I don't conform perfectly to
the protocols on this board!
I'm trying to get an estimate of true prevalence based upon results from an
imperfect test. I have various estimates of se/sp which could inform my
priors (at least upper and lower limits even if with a uniform distribution)
and found the following code on this website..
2012 Aug 15
1
shade overlapping portions of circles (or other shapes)
I'm making some illustrations and it would be convenient to
automatically shade the overlapping portions of circles. These
illustrations are for Social Choice theory, a field in political
science and economics. I've wrestled together some examples so you
can see what I mean, but have not mastered the "color overlapping
sections" problem (as you will see):
2012 Feb 09
1
Constraint on one of parameters.
Dear all,
I have a function to optimize for a set of parameters and want to set a
constraint on only one parameter. Here is my function. What I want to do is
estimate the parameters of a bivariate normal distribution where the
correlation has to be between -1 and 1. Would you please advise how to
revise it?
ex=function(s,prob,theta1,theta,xa,xb,xc,xd,t,delta) {
expo1=
2017 Dec 25
2
[Bug 1206] New: segfault when snat map rule has been added
https://bugzilla.netfilter.org/show_bug.cgi?id=1206
Bug ID: 1206
Summary: segfault when snat map rule has been added
Product: nftables
Version: unspecified
Hardware: x86_64
OS: Ubuntu
Status: NEW
Severity: normal
Priority: P5
Component: nft
Assignee: pablo at netfilter.org
2009 Aug 17
2
Newbie that don't understand R code
I got some R code that I don't understand.
Question as comment in code
//where is t comming from, what is phi inverse
rAC <- function(name, n, d, theta){
#generic function for Archimedean copula simulation
illegalpar <- switch(name,
clayton = (theta < 0),
gumbel = (theta < 1),
frank = (theta < 0),
BB9 = ((theta[1] < 1) | (theta[2] < 0)),
GIG = ((theta[2] < 0) |
2009 Apr 25
3
Nomogram with stratified cph in Design package
Hello,
I am using Dr. Harrell's design package to make a nomogram. I was able to
make a beautiful one without stratifying, however, I will need to stratify
to meet PH assumptions. This is where I go wrong, but I'm not sure where.
Non-Stratified Nomogram: