Displaying 6 results from an estimated 6 matches for "meanses".
2002 May 02
2
problem with lme in nlme package
...-24 of nlme in R 1.4.1 under Windows 2000, and both
S-PLUS 2000 and 6.0, again under Windows 2000.
I've noticed discrepancies in a couple of instances. Here's one, using data
from Bryk and Raudenbush's Hierarchical Linear models:
From R:
> attach(Bryk)
> cses <- meanses <- numeric(length(ses)) # initialize
> for (sc in unique(school)) {
+ meanses[school==sc] <- mean(ses[school==sc])
+ cses[school==sc]<-ses[school==sc]- meanses[school==sc]
+ }
> Bryk$cses <- cses
> Bryk$meanses <- meanses
>...
2004 Jan 07
2
problem assigning an array to a variable in a data frame
...- tapply(SES, School, mean)
> detach(MathAchieve)
> Bryk <- as.data.frame(MathAchieve[, c("School", "SES", "MathAch")])
> names(Bryk) <- c("school", "ses", "mathach")
> sample20 <- sort(sample(7185, 20))
> Bryk$meanses <- mses[as.character(Bryk$school)]
> Bryk[sample20,]
Error in as.data.frame.default(x[[i]], optional = TRUE) :
can't coerce array into a data.frame
>
This is with R 1.8.1 under Windows 2000. The same code works fine with R
1.8.0. As Dirk discovered, the problem disappears...
2003 Jun 25
3
joining columns as in a relational database
In our recent workshop on "Multilevel Modeling in R" we discussed
handling data for multilevel modeling. An classic example of such
data are test scores of students grouped into schools. We may wish to
model the scores as functions of both student-level covariates and
school-level covariates.
Such data are often organized in a multi-table format with a separate table
for each level of
2005 Oct 24
0
aggregating using several functions
Dear R users,
I would like to aggregate a data frame using several functions at once
(e.g., mean plus standard error).
How can I make this work using aggregate()? The help file says scalar
functions are needed; can anyone help?
Below is the code for my "meanse" function which I??d like to use like this:
aggregate(dataframe, list(factorA,factoB),meanse)
Thanks for your help!
2012 May 12
2
Why can we combine design matrix and data-frame in R?
...Pages
•VasishthBroebook.R
•beauty.txt
•mathachieve.txt
•mathachschool.txt
------------------------------
MathAchieve <- read.table("mathachieve.txt")
colnames(MathAchieve) <- c("School", "Minority", "Sex", "SES", "MathAch",
"MEANSES")
head(MathAchieve)
MathAchSchool <- read.table("mathachschool.txt")
colnames(MathAchSchool) <- c("School", "Size", "Sector", "PRACAD",
"DISCLIM", "HIMINTY", "MEANSES")
MathScores <- merge(MathAchieve,...
1998 Mar 05
1
User time and system time
...on the same machine
but R is much slower - like an order of magnitude - than S-PLUS on
this problem.
It looks curious to me when I run system.time() on this that timing
vector shows almost no user time but a huge amount of system time.
R> system.time(assign("fm2",
+ lme(MathAch ~ MEANSES*CSES + Sector + CSES:Sector, ttt, ~ CSES | School,
+ RML = TRUE )))
iteration = 0
Step:
[1] 0 0 0
Parameter:
[1] 2.61400 0.16608 3.88195
Function Value
[1] 44964
Gradient:
[1] -0.014379 -0.143176 -0.646558
iteration = 1
Step:
[1] 0.002888 0.028756 0.129857
Parameter:
[1] 2.61...