Displaying 20 results from an estimated 7000 matches similar to: "Label point with (x,hat(y))"
2012 Jul 21
4
rhsape2 bug?
All,
I believe I am running the latest version of rshape2 (1.2.1). But this code:
library(reshape2)
tmp <- melt(smiths,
id.vars=1:2,
measure.vars=c("age","weight","height"),
variable.name="myvars",
value.name="myvals"
)
names(tmp)
Produces this output:
> names(tmp)
[1] "subject" "time"
2013 Feb 12
2
Data sets online for student use
All,
If you have any good links for sites that contain data sets that can easily
be accessed and copied (or downloaded) by students in introductory
statistics, could you please share them?
Thanks.
David
--
View this message in context: http://r.789695.n4.nabble.com/Data-sets-online-for-student-use-tp4658326.html
Sent from the R help mailing list archive at Nabble.com.
2012 Aug 03
2
Printing a summary
All,
Is this typical of how people will print a summary of results?
CoinTosses <- function(n) {
x <- sample(c(0,1), n, replace=TRUE)
y <- x
y[y==0] <- "T"
y[y==1] <- "H"
numHeads <- sum(x)
numTails <- n-sum(x)
p <- numHeads/n
cat(cat(y,sep=""),"\n")
cat("Number of heads: ", numHeads, "\n")
2013 Sep 17
1
"With" question
All,
Trying to avoid using attach and detach while teaching class in Intro Stats.
data=read.delim("dataset1.dat",header=TRUE)
with(data,{
sort(age)
length(age)
(age[10]+age[11])/2
})
However, this code only produces output for the last line between the curly
braces. Granted, as we type the lines in one at a time and execute the code,
we'll see each output. And, we can fix
2012 Nov 29
2
Analysis of Variance
Hi, I am encountering a difficulty I don't understand. Be patient, I'm very
new to analysis of variance.
If I load this data:
example12_7=read.table("http://msemac.redwoods.edu/~darnold/math15/data/chapter12/example12_7.dat",header=TRUE)
The run the oneway.test:
oneway.test(time~drug,data=example12_7,var.equal=TRUE)
I get these results:
data: time and drug
F = 4.1881, num
2012 Aug 15
4
Reading one column .csv file
My friend sent an Excel file:
http://msemac.redwoods.edu/~darnold/temp/cyu01_iqscores.xls
http://msemac.redwoods.edu/~darnold/temp/cyu01_iqscores.xls
I opened it in Excel, saved is as cyu01_iqscores.csv, then imported it into
R with:
iqscores=read.csv('cyu01_iqscores.csv',header=TRUE)
The result was:
> head(iqscores)
IQ.Scores X
1 145 NA
2 101 NA
3 123 NA
4
2002 Mar 08
1
Matrix multiplication problem
Dear List,
I am having trouble with some R code I have written to perform
Redundancy Analysis (RDA) on a matrix of species abundance data (Y) and
a matrix of environmental data (X).
RDA is a constrained form of PCA and can be thought of as a PCA of the
fitted values of a regression of each variable in Y on all variables in
X.
For info, the first use of RDA is in:
Rao, C.R, 1964. The use and
2011 May 08
1
Hosmer-Lemeshow 'goodness of fit'
I'm trying to do a Hosmer-Lemeshow 'goodness of fit' test on my logistic
regression model.
I found some code here:
http://sas-and-r.blogspot.com/2010/09/example-87-hosmer-and-lemeshow-goodness.html
The R code is above is a little complicated for me but I'm having trouble
with my answer:
Hosmer-Lemeshow: p=0.6163585
le Cessie and Houwelingen test (Design library): p=0.2843620
2012 Jul 18
4
Entering Data Files
Hi,
Entering data from a given file is the hardest part of learning R for me.
For example, I have this datafile from Moore's text:
Live Age Count
Parents Age19 324
Another Age19 37
OwnPlace Age19 116
Group Age19 58
Other Age19 5
Parents Age20 378
Another Age20 47
OwnPlace Age20 279
Group Age20 60
Other Age20 2
Parents Age21 337
Another Age21 40
OwnPlace Age21 372
Group Age21 49
Other Age21 3
2012 Jul 12
4
Adjusting format of boxplot
Hi,
I managed to use the attached data set and figure out the following:
flies <- read.table("example12_1.dat",header=TRUE,sep="\t")
boxplot(long ~ group,
data = flies,
horizontal = TRUE,
col = "red")
I'm very new to R and would like some help with the following:
1. Change the order on the y-axis from 1, 2, 3, 4, 5 to 5, 4, 3, 2, 1.
2010 Jan 16
2
predict.glm
Hi,
See below I reply your message for <https://stat.ethz.ch/pipermail/r-help/2008-April/160966.html>[R] predict.glm & newdata posted on Fri Apr 4 21:02:24 CEST 2008
You say it ##works fine but it does not: if you look at the length of yhat2, you will find 100 and not 200 as expected. In fact predict(reg1, data=x2) gives the same results as predict(reg1).
So I am still looking for
2001 Apr 27
3
nls question
I have a question about passing arguments to the function f that nlm
minimizes.
I have no problems if I do this:
x<-seq(0,1,.1)
y<-1.1*x + (1-1.1) + rnorm(length(x),0,.1)
fn<-function(p)
{
yhat<-p*x+(1-p)
sum((y-yhat)^2)
}
out<-nlm(fn,p=1.5,hessian=TRUE)
But I would like to define
fn<-function(x,y,p)
{
yhat<-p*x+(1-p)
sum((y-yhat)^2)
}
so
2012 Mar 08
1
sas retain statement in R or fitting differene equations in NLS
I wish to fit a dynamical model in R and I am running in a problem that
requires some of your wisdom to solve. For SAS users I am searching for
the equivalent of the */retain/ *statement.
For people that want to read complicated explanations to help me:
I have a system of two equations written as difference equations here.
To boil it down. I have a dataframe with three variables y, X1, X2
2010 Feb 13
2
lm function in R
Hello,
I am trying to learn how to perform Multiple Regression Analysis in R. I
decided to take a simple example given in this PDF:
http://www.utdallas.edu/~herve/abdi-prc-pretty.pdf
I created a small CSV called, students.csv that contains the following data:
s1 14 4 1
s2 23 4 2
s3 30 7 2
s4 50 7 4
s5 39 10 3
s6 67 10 6
Col headers: Student id, Memory span(Y), age(X1), speech rate(X2)
Now
2008 Sep 16
2
Hosmer- Lemeshow test
Dear R - help,
I am working on the Credit scorecard model. I am using the Logistic regression to arrive at the regression coefficients model.
I want to use the Hosmer - Lemeshow test .
In order to understand the use of R - language, I had referred the following URL
http://www.stat.sc.edu/~hitchcock/diseaseoutbreakRexample704.txt
The related data 'diseaseoutbreak' is available
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
2013 Apr 23
1
Hosmer Lemeshow test
Hi to everybody. I use the following routine (i found it in the internet)
to compute the Hosmer-Lemeshow test in the framework of logistic regression.
hosmerlemeshow = function(obj, g=10) {
# first, check to see if we fed in the right kind of object
stopifnot(family(obj)$family=="binomial" && family(obj)$link=="logit")
y = obj$model[[1]]
# the double bracket
2008 Nov 07
1
two kind of Hosmer and Lemeshow’s test
I know that there are two method to apply the Hosmer and Lemeshow?s. One of
them is calculated based on the fixed and pre-determined cut-off points of
the estimated probability of success. One of them is calculated based on
the percentiles of estimated probabilities.
In the previous post,i find that the Hosmer and Lemeshow?s test how to use
in R.
hosmerlem <-
function (y, yhat, g = 10)
{
2010 Apr 25
1
function pointer question
Hello,
I have the following function that receives a "function pointer" formal parameter name "fnc":
loocv <- function(data, fnc) {
n <- length(data.x)
score <- 0
for (i in 1:n) {
x_i <- data.x[-i]
y_i <- data.y[-i]
yhat <- fnc(x=x_i,y=y_i)
score <- score + (y_i - yhat)^2
}
score <- score/n
2012 Nov 16
2
R-Square in WLS
Hi,
I am fitting a weighted least square regression and trying to compute
SSE,SST and SSReg but I am not getting SST = SSReg + SSE and I dont know
what I am coding wrong. Can you help please?
xnam <-colnames(X) # colnames Design Matrix
fmla1 <- as.formula(paste("Y ~",paste(xnam, collapse=