Displaying 20 results from an estimated 10000 matches similar to: "Reducing a matrix"
2010 Feb 25
2
Rearranging entries in a matrix
I have a matrix, called data. I used the code below to rearrange the data such that the first column remains the same, but the y value falls under either columns 2, 3 or 4, depending on the value of z. If z=1 for example, then the value of y will fall under column 2, if z=2, the value of y falls under column 3, and so on.
data
x y z
[1,] 50 13 1
[2,] 14 8 2
[3,] 3 7 3
[4,] 4 16 1
[5,] 6
2011 Aug 15
1
update() ignores object
Hi all,
I'm extracting the name of the term in a regression model that
dropterm specifies as the least significant one, and I'm assigning
this name to an object. However, when I use update(), it ignores this
object. Is there a way I can make it not ignore it? A reproducible
example is below:
> lm(x1~1+y1*y2+y3+y4,data=anscombe)->my.lm
>
2008 Dec 29
4
Merge or combine data frames with missing columns
Hi R-experts,
suppose I have a list with containing data frame elements:
[[1]]
(Intercept) y1 y2 y3 y4
-6.64 0.761 0.383 0.775 0.163
[[2]]
(Intercept) y2 y3
-3.858 0.854 0.834
Now I want to put them into ONE dataframe like this:
(Intercept) y1
2008 Aug 13
1
summary.manova rank deficiency error + data
Dear R-users;
Previously I posted a question about the problem of rank deficiency in
summary.manova. As somebody suggested, I'm attaching a small part of
the data set.
#***************************************************
"test" <-
structure(.Data = list(structure(.Data = c(rep(1,3),rep(2,18),rep(3,10)),
levels = c("1", "2", "3"),
class =
1998 Nov 09
2
no subject (file transmission)
RNG in R and Splus 3.4
Prof. Ripley asked the details of the example.
We were doing parametric bootstrap, so it is similar to simulation.
Anyway here is the details.
We start with a sample of 19 positive numbers. We know the sample
is from truncated exp(0.3)...only the truncation point, theta, is unknown.
In other words, the sample can be generated from something like
x1 <- rexp(100,
1998 Nov 09
2
no subject (file transmission)
RNG in R and Splus 3.4
Prof. Ripley asked the details of the example.
We were doing parametric bootstrap, so it is similar to simulation.
Anyway here is the details.
We start with a sample of 19 positive numbers. We know the sample
is from truncated exp(0.3)...only the truncation point, theta, is unknown.
In other words, the sample can be generated from something like
x1 <- rexp(100,
2004 Feb 26
2
Structural Equation Model
Hello all!
I want to estimate parameters in a MIMIC model. I have one latent
variable (ksi), four reflexive indicators (y1, y2, y3 and y4) and four
formative indicators (x1, x2, x3, x4). Is there a way to do it in R? I
know there is the SEM library, but it seems not to be possible to
specify formative indicators, that is, observed exogenous variables
which causes the latent variable.
Thanks,
2006 Aug 29
2
lattice/xyplot: plotting 4 variables in two panels - can this be done?
Hi,
I would like to create a plot of y1,y2,y3,y4 against x for several subjects such that y1 and y2 are plotted against x in one panel and y3 and y4 against x in another panel. Thus if there are 3 subjects I should end up with 6 panels. Is there a simple way of doing so (i.e. without calling xyplot() several times, and then padding the results together)??
Regards
S?ren
2011 May 12
2
group length
Hi
I have four groups
y1=c(1.214,1.180,1.199)
y2=c(1.614,1.710,1.867,1.479)
y3=c(1.361,1.270,1.375,1.299)
y4=c(1.459,1.335)
Is there a function that can give me the length for each, like the made up
example below?
>function(length(y1:y2)
[1] 3 4 4 2
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2008 May 14
2
mfrow
Dear members,
I want to create 8 graphs and write it into one page using mfrow=c(4,2).
How to make all graphs (including the titles, legends, line types) to be
scale down (resized proportionally).
As an illustration, below is the code:
pdf("testmfrow.pdf")
par(mfrow=c(4,2))
x<-seq(1:10)
y1<-rnorm(10)
y2<-rnorm(10,mean=2,sd=1)
y3<-rnorm(10,mean=3,sd=1)
[R-pkgs] New package: `lavaan' for latent variable analysis (including structural equation modeling)
2010 May 24
2
[R-pkgs] New package: `lavaan' for latent variable analysis (including structural equation modeling)
Hi Yves
lavaan looks like a very nice package. From the tutorial introduction
I see you create path diagrams for some of the models you describe.
How did you do this? I don't see a function for this in the package.
I know there is a path.diagram function in the sem package that uses
dot to draw the diagram, but I've always found the layouts from dot
somewhat strange for path diagrams
2002 May 11
2
modelling a particular design
Dear R- and Omega-list-members,
I am trying to make statistical inference about the following design:
A dependent variable y has been measured multiple times, i.e. 4 times
(y1,y2, y3, y4), unfortunately suffering from some successive dropouts (i.e.
the sample sizes varies for y1, y2, y3, and y4). For every y, two other
variables (covariates) were also measured: x & z, and both do presumably
2005 May 24
1
Contingency tables from data.frames
Dear list,
I'm trying to do a set of generic functions do make contingency tables from
data.frames. It is just running "nice" (I'm learning R), but I think it can be
better.
I would like to filter the data.frame, i.e, eliminate all not numeric variables.
And I don't know how to make it: please, help me.
Below one of the my functions ('er' is a mention to EasieR,
2018 Feb 12
3
plotting the regression coefficients
Hi
After melt you can change levels of your factor variable. Again with the toy example.
> levels(temp$variable)
[1] "y1" "y2" "y3" "y4"
> levels(temp$variable) <- levels(temp$variable)[c(2,4,1,3)]
> levels(temp$variable)
[1] "y2" "y4" "y1" "y3"
>
And you will get graphs with this new levels ordering.
2007 Dec 05
1
Working with "ts" objects
I am relatively new to R and object oriented programming. I have relied on
SAS for most of my data analysis. I teach an introductory undergraduate
forecasting course using the Diebold text and I am considering using R in
addition to SAS and Eviews in the course. I work primarily with univariate
or multivariate time series data. I am having a great deal of difficulty
understanding and working with
2017 Jul 16
0
Arranging column data to create plots
On Sat, 15 Jul 2017, Michael Reed via R-help wrote:
> Dear All,
>
> I need some help arranging data that was imported.
It would be helpful if you were to use dput to give us the sample data
since you say you have already imported it.
> The imported data frame looks something like this (the actual file is
> huge, so this is example data)
>
> DF:
> IDKey X1 Y1 X2 Y2
2006 Aug 10
2
index.cond in xyplot
Dear R-users
I have 5 dependent variables (y1 to y5) and one independent variable (x) and
3 conditioning variables (m, n, and 0). Each of the conditioning variables
has 2 levels. I created 2*4 panel plots.
xyplot(y1+y2+y3+y4+y5 ~ x | m*n*o,layout = c(4,2))
I would like to reorder the 8 panels. I tried to use index.cond (e.g.,
index.cond = list(c(1,3,2,4,5,7,6,8)) but it didn't work out.
2012 Jul 31
2
help with a regression
Hello, I have a data frame with the following variables:
ID, X1,X2,X3,X4,X5,Y1,Y2,Y3,Y4,Y5 and some other that do not matter, some of the X and Y can be missing (NA). I want to compute the slope of the linear regression Y ~ X for each subject, so using
apply(DF,1,FUN,ra.rm=TRUE) now How do I define FUN? The X are different for each subject.
Thanks for any help
R.Heberto Ghezzo Ph.D.
Montreal -
2012 Apr 10
1
cbind, data.frame | numeric to string?
Complete newbie to R -- struggling with something which should be pretty
basic. Trying to create a simple data set (which I gather R refers to as a
data.frame). So
> a <- c(1,2,3,4,5);
> b <- c(0.3,0.4,0.5,0,6,0.7);
Stick the two together into a data frame (call test) using cbind
> test <- data.frame(cbind(a,b))
Seems to do the trick:
> test
a b
1 1 0.3
2 2 0.4
3 3
2018 Feb 12
0
plotting the regression coefficients
Petr, there was a thinko in your response.
tmp <- data.frame(m=factor(letters[1:4]), n=1:4)
tmp
tmp$m <- factor(tmp$m, levels=c("c","b","a","d")) ## right
tmp[order(tmp$m),]
tmp <- data.frame(m=factor(letters[1:4]), n=1:4)
levels(tmp$m) <- c("c","b","a","d") ## wrong
tmp[order(tmp$m),]
changing levels