Displaying 20 results from an estimated 10000 matches similar to: "Memory consumption, integer versus factor"
2006 Mar 06
3
Interleaving elements of two vectors?
Suppose one has
x <- c(1, 2, 7, 9, 14)
y <- c(71, 72, 77)
How would one write an R function which alternates between elements of
one vector and the next? In other words, one wants
z <- c(x[1], y[1], x[2], y[2], x[3], y[3], x[4], y[4], x[5], y[5])
I couldn't think of a clever and general way to write this. I am aware
of gdata::interleave() but it deals
2005 May 08
2
Need a factor level even though there are no observations
I'm in this situation:
factorlabels <- c("School", "College", "Beyond")
with data for 8 families:
education.man <- c(1,2,1,2,1,2,1,2) # Note : no "3" values
education.wife <- c(1,2,3,1,2,3,1,2) # 1,2,3 are all present.
My goal is to create this table:
School College Beyond
2008 Dec 22
1
sem package fails when no of factors increase from 3 to 4
#### I checked through every 3 factor * 3 loading case.
#### While, 4 factor * 3 loading failed.
#### the data is 6 factor * 3 loading
require(sem);
cor18<-read.moments();
1
.68 1
.60 .58 1
.01 .10 .07 1
.12 .04 .06 .29 1
.06 .06 .01 .35 .24 1
.09 .13 .10 .05 .03 .07 1
.04 .08 .16 .10 .12 .06 .25 1
.06 .09 .02 .02 .09 .16 .29 .36 1
.23 .26 .19 .05 .04 .04 .08 .09 .09 1
.11 .13 .12 .03 .05 .03
2011 Jun 23
0
Loops, Paste, Apply? What is the best way to set up a list of many equations?
Is there a way to apply paste to?list(form1 = EQ1, form2 = EQ2, form3 = EQ3, form4 = EQ4)?such that I don't have to write form1=EQ1 for all my models?(I might have a list of 20 or more)? I also need the EQs to read the formulas associated with them.
For example, below, I was able to automate the name assignment but I could not figure out how to?to set up the list using?paste or other
2013 Apr 13
1
how to add a row vector in a dataframe
Hi,
Using S=1000
and
simdata <- replicate(S, generate(3000))
#If you want both "m1" and "m0" #here the missing values are 0
res1<-sapply(seq_len(ncol(simdata.psm1)),function(i) {x1<-merge(simdata.psm0[,i],simdata.psm1[,i],all=TRUE); x1[is.na(x1)]<-0; x1})
res1[,997:1000]
#????? [,1]???????? [,2]???????? [,3]???????? [,4]???????
#x1??? Numeric,3000 Numeric,3000
2006 Jan 26
2
Prediction when using orthogonal polynomials in regression
Folks,
I'm doing fine with using orthogonal polynomials in a regression context:
# We will deal with noisy data from the d.g.p. y = sin(x) + e
x <- seq(0, 3.141592654, length.out=20)
y <- sin(x) + 0.1*rnorm(10)
d <- lm(y ~ poly(x, 4))
plot(x, y, type="l"); lines(x, d$fitted.values, col="blue") # Fits great!
all.equal(as.numeric(d$coefficients[1] + m
2005 Jun 07
1
R and MLE
I learned R & MLE in the last few days. It is great! I wrote up my
explorations as
http://www.mayin.org/ajayshah/KB/R/mle/mle.html
I will be most happy if R gurus will look at this and comment on how
it can be improved.
I have a few specific questions:
* Should one use optim() or should one use stats4::mle()?
I felt that mle() wasn't adding much value compared with optim, and
2005 May 27
1
R commandline editor question
I am using R 2.1 on Apple OS X.
When I get the ">" prompt, I find it works well with emacs commandline
editing. Keys like M-f C-k etc. work fine.
The one thing that I really yearn for, which is missing, is bracket
matching When I am doing something which ends in )))) it is really
useful to have emacs or vi-style bracket matching, so as to be able
to visually keep track of whether I
2005 Aug 19
1
Problem with get.hist.quote() in tseries
When using get.hist.quote(), I find the dates are broken. This is with
R 2.1.1 on Mac OS X `panther'.
> library(tseries)
Loading required package: quadprog
'tseries' version: 0.9-27
'tseries' is a package for time series analysis and computational
finance.
See 'library(help="tseries")' for details.
> x <-
2005 Jul 12
2
Puzzled at ifelse()
I have a situation where this is fine:
> if (length(x)>15) {
clever <- rr.ATM(x, maxtrim=7)
} else {
clever <- rr.ATM(x)
}
> clever
$ATM
[1] 1848.929
$sigma
[1] 1.613415
$trim
[1] 0
$lo
[1] 1845.714
$hi
[1] 1852.143
But this variant, using ifelse(), breaks:
> clever <- ifelse(length(x)>15, rr.ATM(x, maxtrim=7), rr.ATM(x))
2005 May 24
1
Catching an error with lm()
Folks,
I'm in a situation where I do a few thousand regressions, and some of
them are bad data. How do I get back an error value (return code such
as NULL) from lm(), instead of an error _message_?
Here's an example:
> x <- c(NA, 3, 4)
> y <- c(2, NA, NA)
> d <- lm(y ~ x)
Error in lm.fit(x, y, offset = offset, singular.ok = singular.ok, ...) :
0 (non-NA) cases
2005 Jun 14
1
Puzzled in utilising summary.lm() to obtain Var(x)
I have a program which is doing a few thousand runs of lm(). Suppose
it is a simple model
y = a + bx1 + cx2 + e
I have the R object "d" where
d <- summary(lm(y ~ x1 + x2))
I would like to obtain Var(x2) out of "d". How might I do it?
I can, of course, always do sd(x2). But it would be much more
convenient if I could snoop around the contents of summary.lm and
2005 Aug 16
1
Extracting some rows from a data frame - lapses into a vector
I have a data frame with one column "x":
> str(data)
`data.frame': 20 obs. of 1 variable:
$ x: num 0.0495 0.0986 0.9662 0.7501 0.8621 ...
Normally, I know that the notation dataframe[indexes,] gives you a new
data frame which is the specified set of rows. But I find:
> str(data[1:10,])
num [1:10] 0.0495 0.0986 0.9662 0.7501 0.8621 ...
Here, it looks like the operation
2005 Sep 25
1
Question on lm(): When does R-squared come out as NA?
I have a situation with a large dataset (3000+ observations), where
I'm doing lags as regressors, where I get:
Call:
lm(formula = rj ~ rM + rM.1 + rM.2 + rM.3 + rM.4)
Residuals:
1990-06-04 1994-11-14 1998-08-21 2002-03-13 2005-09-15
-5.64672 -0.59596 -0.04143 0.55412 8.18229
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) -0.003297 0.017603
2006 Aug 14
1
Presentation of multiple models in one table using xtable
Consider this situation:
> x1 <- runif(100); x2 <- runif(100); y <- 2 + 3*x1 - 4*x2 + rnorm(100)
> m1 <- summary(lm(y ~ x1))
> m2 <- summary(lm(y ~ x2))
> m3 <- summary(lm(y ~ x1 + x2))
Now you have estimated 3 different "competing" models, and suppose you
want to present the set of models in one table. xtable(m1) is cool,
but doing that thrice would give
2008 Sep 28
1
reshape package does not recognize second id variable
I am trying to use the reshape package for the first time. I have two
waves of a survey, so the id variables include a subject
identification number and a variable denoting the wave of the survey.
I used the following arguments:
library(reshape)
svy.melt <- melt(svy, id=c("id", "WAVE"))
svy.wide <- cast(svy.melt, id ~ WAVE + ...)
and got the following error:
2007 May 16
1
partial least regression
hello r-helpers:
there is a .txt file:
x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 y1
17 5 77 18 19 24 7 24 24 72 52 100
2 6 72 18 17 15 4 12 18 35 42 97.2
17 2 58 10 5 3 4 3 3 40 28 98
17 2 69 14 13 12 4 6 6 50 37 93
2 3 75 20 38 18 6 12 18 73 67 99
14 4 59 16 18 9 4 3 15 47 40 99.95
17 4 87 18 17 12 4 15 12 69 46 100
14 3 74 15 9 12 1 15 12 44 35 98
17 6 76 15 33 21 15 9 18 46 41 100
17 5 76 17 22 18 1
2005 Oct 01
1
Placing axes label strings closer to the graph?
Folks,
I have placed an example of a self-contained R program later in this
mail. It generates a file inflation.pdf. When I stare at the picture,
I see the "X label string" and "Y label string" sitting lonely and far
away from the axes. How can these distances be adjusted? I read ?par
and didn't find this directly.
I want to hang on to 2.8 x 2.8 inches as the overall size
2006 Nov 17
2
Data table in C
After getting one list done, I am now struggling to form a data frame in C.
I tried to do a list of lists which gives me :
$<NA>
$<NA>[[1]]
[1] "BID"
$<NA>[[2]]
[1] 0.6718
$<NA>[[3]]
[1] 3e+06
$<NA>
$<NA>[[1]]
[1] "BID"
$<NA>[[2]]
[1] 0.6717
$<NA>[[3]]
[1] 5e+06
$<NA>
$<NA>[[1]]
[1] "BID"
2005 Aug 04
1
Puzzled at rpart prediction
I'm in a situation where I say:
> predict(m.rpart, newdata=D[N1+t,])
0 1
173 0.8 0.2
which I interpret as meaning: an 80% chance of "0" and a 20% chance of
"1". Okay. This is consistent with:
> predict(m.rpart, newdata=D[N1+t,], type="class")
[1] 0
Levels: 0 1
But I'm puzzled at the following. If I say:
> predict(m.rpart,