Displaying 20 results from an estimated 10000 matches similar to: "xtabs to dataframe fails (PR#3754)"
2003 Nov 06
1
Question about computing offsets automatically
Hi,
I'm using R version 1.8.0 on Windows NT. When fitting a glm with Poisson
random component and a log link, I frequently need to include an offset.
Typically I use xtabs or table to get the counts for the contingency table,
and then I use as.data.frame.table to create a data frame that I can use in
the glm function. I have not found an option that allows me to total the
offset variable to
2007 Jan 09
1
contingency table analysis; generalized linear model
Dear List,
I would appreciate help on the following matter:
I am aware that higher dimensional contingency tables can be analysed using either log-linear models or as a poisson regression using a generalized linear model:
log-linear:
loglm(~Age+Site, data=xtabs(~Age+Site, data=SSites.Rev, drop.unused.levels=T))
GLM:
glm.table <- as.data.frame(xtabs(~Age+Site, data=SSites.Rev,
2016 May 23
2
data frame method for as.table()
Hello,
Currently it's possible to convert an object of class table to a data frame
with as.data.frame.table(), but there's no ready-made function, AFAIK, to do
the reverse operation, i.e. conversion of a data frame to a table.
Do you think it would be a good idea to add a data.frame method to
as.table(), to allow such conversions?
The idea is that if `x' is a table and `y <-
2009 Dec 13
1
xtabs - missing combination
Dear list,
I am trying to make a contingency table with xtabs but I am getting
a 0 where I expect a 'NA'. Here is a simple example:
options(stringsAsFactors = FALSE)
rn <- LETTERS[1:4]
df1 <- data.frame(r07 = rep(rn, each=4),
r08 = rep(rn, 4), value = 1:16)
xtabs(value ~ r07 + r08, df1)
# Delete the combination [A, C]
df1 <- df1[-3,]
# Set 'value'
2008 Mar 29
1
Tabulating Sparse Contingency Table
I have a sparse contingency table (most cells are 0):
> xtabs(~.,data[,idx:(idx+4)])
, , x3 = 1, x4 = 1, x5 = 1
x2
x1 1 2 3
1 0 0 31
2 0 0 112
3 0 0 94
, , x3 = 2, x4 = 1, x5 = 1
x2
x1 1 2 3
1 0 0 0
2 0 0 0
3 0 0 0
, , x3 = 3, x4 = 1, x5 = 1
x2
x1 1 2 3
1 0 0 0
2 0 0 0
3 0 0 0
, , x3 = 1, x4
2003 Apr 30
1
sorting factors
Hi,
I've been trying to sort the values of the factors of contingency tables
generated with xtabs. For example, I have a factor called "artic" with three
possible values that I would like to order in a specific way -- but I'm not
sure how to go about this.
> test <- read.table("test.tab",header=TRUE,sep="\t")
> artic =
2009 Apr 24
2
argument 'exclude' in function xtabs
Dear all
I was willing to use argument 'exclude' in function xtabs to remove some
levels of factors (xtabs help page says '"exclude: a vector of values to be
excluded when forming the set of levels of the classifying factors").
I tried:
> mydata <- data.frame(
treatment = c("B", "A", "C", "C", "B",
2007 Oct 05
1
creating objects of class "xtabs" "table" in R
I have an application that would generate a cross-tabulation in array
format in R. In particular, my application would give me a result
similar to that of :
array(5,c(2,2,2,2,2))
The above could be seen as a cross-tabulation of 5 variables with 2
levels each (could be 0 and 1). In this case, the data were such that
each cell has exactly 5 observations. I
Now, I want the output to look like the
2011 Aug 16
1
getting names of dimnames of xtabs into xtable latex output
In R, the output of xtabs displays the names of the dimnames. In the
example below, these are "change_diet" and "mydiet". Is there a way to
have xtable incorporate these names directly into the latex output.
Thanks for your help.
table2 <- structure(c(26, 0, 40, 0, 10, 0, 188, 0, 281, 0), .Dim = c(5L,
2L), .Dimnames = structure(list(change_diet = c("Don't
2005 Nov 17
1
transforming table into data frame
Hello,
I would like to transform a contingency table (A x B) into a data
frame while keeping the cross-tabulation structure (i.e. rows =
levels of A, columns = levels of B). I have tried as.data.frame,
xtabs, etc... and always got a "flattened" list of 3 variables (A, B,
Freq).
How to do that?
Thanks in advance
Charles Raux
2011 Jun 24
1
Converting an ftable (contingency table) to a dataframe in R
I am generating an ftable (by running ftable on the results of a xtabs command) and I am getting the following.
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Var1? Var2
date ? ? ? ? ? ? ? ? group? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
2007-01-01? ? ? ? ? q1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?1? ? 9
? ? ? ? ? ? ? ? ? ? ?q2 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?
2002 Feb 13
3
xtabs
Hi,
In Splus if I call the function crosstabs() the output is a contigency
table; in each cell of the table is printed: N, N/RowTotal,
N/ColTotal, N/Total. N is the number of observations in each cell.
The same call to xtabs() in R will produce the contigency table but the
only entry in each cell is N.
How can I get the same relative frequencies that crosstabs() gives?
Thanks,
mike
--
2003 Dec 02
0
xtabs or model.frame (PR#5461)
# Your mailer is set to "none" (default on Windows),
# hence we cannot send the bug report directly from R.
# Please copy the bug report (after finishing it) to
# your favorite email program and send it to
#
# r-bugs@r-project.org
#
######################################################
Here is the bug report I got from Professor Hsuan, and my exploration
of it. The cause of the
2003 May 14
2
how to include 'NA's in xtabs?
Hello!
I have a dataset with NA's in some variables (factors), for example:
$ P67 : Factor w/ 2 levels "-","+": NA 2 1 NA NA 2 1 1 2 NA ...
I need to use 'xtabs' like
xtabs(~x$P67)
It works well and produces something like this:
x$P67
- +
779 1318
but i want to compute NA's too, like this:
x$P67
- + NA
779 1318 137
I am trying
2010 Nov 08
1
unknown dimensions for loglm
Dear R-help community,
I am working with multidimensional contingency tables and I am having
trouble getting loglm to run on all dimensions without typing out each
dimension.
I have generated random data and provided output for the results I want
below:
d1.c1 <- rnorm(20, .10, .02)
d1.c2 <- rnorm(20, .10, .02)
d2.c1 <- rnorm(20, .09, .02)
d2.c2 <- rnorm(20, .09, .02)
d3.c1 <-
2009 Sep 04
1
Problem with xtabs(), exclude=NULL, and counting NA's
Hi all,
I cannot get xtabs to count NA's like I expect. Below is a sample session, and
note that the last two calls to xtabs() yield exactly the same thing.
I am running R-2.5.0 -- if there was a bug in xtabs that got fixed, I would love
to know about it. If there is a bug tracker somewhere, I can file it too. It
isn't my fault that the server is so ridiculously outdated, but I would
2015 Feb 09
3
xtabs and NA
Hi
I haven't found a way to produce a tabulation from factor data with NA
values using xtabs. Please find a minimal example below, it's also on
R-pubs [1]. Tested with R 3.1.2 and R-devel r67720.
It doesn't seem to be documented explicitly that it's not supported.
From reading the code [2] it looks like the relevant call to table()
doesn't set the "useNA"
2005 Mar 22
1
List of tables rather than an extra dimension in the table or (l)apply(xtabs)
I'm not sure how to best explain what I am after but here goes. I have a data frame with 2 geographical factors. One is the major region the other is the component regions.
I am trying to process all the regions at the same time without using "for". So I need (think, I do) a list of matrices each structured according to the number of subregions within each region.
So is there a
2004 Nov 29
1
Seeking help with a simple loop construction
Hello,
I have a df, pp, with five variables:
> nobs(pp)
q10_1 q10_2 q10_3 q10_4 actcode
1620 1620 1620 1620 1620
I want to create a loop to run four xtabs (the first four variables above by the fifth) and then store the results in a matrix. Below I make my intent clear by showing the output of one xtab which is inserted into a matrix.
> a <- xtabs(q10_1 ~
2010 Apr 18
3
xtabs() of proportions, and naming a dimension (not a row)
Hi,
xtabs() creates a table of counts. I want a table of proportions -- that
is, I want to divide every vector (along a particular dimension) by its sum.
The tiny example below does that. The call to xtabs() creates a matrix "A"
with dimensions ("x1","x2","y"). I transform "A" using aperm() and aaply()
to get the matrix "B". The