Displaying 20 results from an estimated 1000 matches similar to: "Random selection from a subsample"
2018 Jan 07
2
SpreadLevelPlot for more than one factor
Dear Ashim,
Try spreadLevelPlot(breaks ~ interaction(tension, wool), data=warpbreaks) .
I hope this helps,
John
-----------------------------
John Fox, Professor Emeritus
McMaster University
Hamilton, Ontario, Canada
Web: socialsciences.mcmaster.ca/jfox/
> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Ashim
> Kapoor
> Sent:
2009 Jan 14
3
Casting lists to data.frames, analog to SAS
I have a specific question and a general question.
Specific Question: I want to do an analysis on a data frame by 2 or more
class variables (i.e., use 2 or more columns in a dataframe to do
statistical classing). Coming from SAS, I'm used to being able to take a
data set and have the output of the analysis in a dataset for further
manipulation. I have a data set with vote totals, with one
2018 Jan 07
2
SpreadLevelPlot for more than one factor
Dear All,
I want a transformation which will make the spread of the response at all
combinations
of 2 factors the same.
See for example :
boxplot(breaks ~ tension * wool, warpbreaks)
The closest I can do is :
spreadLevelPlot(breaks ~tension , warpbreaks)
spreadLevelPlot(breaks ~ wool , warpbreaks)
I want to do :
spreadLevelPlot(breaks ~tension * wool, warpbreaks)
But I get :
>
2012 Nov 29
2
Deleting certain observations (and their imprint?)
I'm manipulating a large dataset and need to eliminate some observations based on specific identifiers. This isn't a problem in and of itself (using which.. or subset..) but an imprint of the deleted observations seem to remain, even though they have 0 observations. This is causing me problems later on. I'll use the dataset warpbreaks to illustrate, I apologize if this isn't in
2020 May 02
1
issues with environment handling in model.frame()
Dear all,
model.frame behaves in a way I don't expect when both its formula and
subset argument are passed through a function call.
This works as expected:
model.frame(~wool, warpbreaks, breaks < 15)
#> wool
#> 14 A
#> 23 A
#> 29 B
#> 50 B
fun1 <- function(y) model.frame(~wool, warpbreaks, y)
fun1(with(warpbreaks, breaks < 15))
#> wool
#> 14
2018 Jan 09
0
SpreadLevelPlot for more than one factor
Dear Sir,
Many thanks for your reply.
I have a query.
I have a whole set of distributions which should be made normal /
homoscedastic. Take for instance the warpbreaks data set.
We have the following boxplots for the warpbreaks dataset:
a. boxplot(breaks ~ wool)
b. boxplot(breaks ~ tension)
c. boxplot(breaks ~ interaction(wool,tension))
d. boxplot(breaks ~ wool @ each level of tension)
e.
2018 Jan 14
1
SpreadLevelPlot for more than one factor
Dear Ashim,
I?ll address your questions briefly but they?re really not appropriate for
this list, which is for questions about using R, not general statistical
questions.
(1) The relevant distribution is within cells of the wool x tension
cross-classification because it?s the deviations from the cell means that
are supposed to be normally distributed with equal variance. In the
warpbreaks data
2007 Aug 14
4
Problem with "by": does not work with ttest (but with lme)
Hello,
I would like to do a large number of e.g. 1000 paired ttest using the by-function. But instead of using only the data within the 1000 groups, R caclulates 1000 times the ttest for the full data set(The same happens with Wilcoxon test). However, the by-function works fine with the lme function.
Did I just miss something or is it really not working? If not, is there any other possibility to
2011 Dec 15
2
lm and R-squared (newbie)
Hello,
I've two data.frames (data1 and data4), dec="." and sep=";".
http://r.789695.n4.nabble.com/file/n4199964/data1.txt data1.txt
http://r.789695.n4.nabble.com/file/n4199964/data4.txt data4.txt
When I do
plot(data1$nx,data1$ny, col="red")
points(data4$nx,data4$ny, col="blue")
, results seem very similar (at least to me) but the R-squared of
2003 Sep 11
1
samba samba-3.0.0rc3 make install error
Hi all,
I am trying to compile samba-3.0.0rc3 on solaris9 x86
make install booms out with an error.
./configure --prefix=/data4/samba --with-profiling-data --with-quotas --with-sys-quotas
--with-acl-support
make
make install
....
....
Installing bin/CP850.so as /data4/samba/lib/charset/CP850.so
Installing bin/CP437.so as /data4/samba/lib/charset/CP437.so
./install-sh -c bin/libsmbclient.so
2007 Sep 06
3
Warning message with aggregate function
Dear all,
When I use aggregate function as:
attach(warpbreaks)
aggregate(warpbreaks[, 1], list(wool = wool, tension = tension), sum)
The results are right but I get a warning message:
"number of items to replace is not a multiple of replacement length."
BTW: I use R version 2.4.1 in Ubuntu 7.04.
Your kind solutions will be great appreciated.
Best wishes
Yours, sincerely,
Xingwang
2018 Jan 07
0
SpreadLevelPlot for more than one factor
Dear All,
we need to do :
library(car) for the spreadLevelPlot function
I forgot to say that.
Apologies,
Ashim
On Sun, Jan 7, 2018 at 10:37 AM, Ashim Kapoor <ashimkapoor at gmail.com> wrote:
> Dear All,
>
> I want a transformation which will make the spread of the response at all
> combinations
> of 2 factors the same.
>
> See for example :
>
>
2005 May 15
3
adjusted p-values with TukeyHSD?
hi list,
i have to ask you again, having tried and searched for several days...
i want to do a TukeyHSD after an Anova, and want to get the adjusted
p-values after the Tukey Correction.
i found the p.adjust function, but it can only correct for "holm",
"hochberg", bonferroni", but not "Tukey".
Is it not possbile to get adjusted p-values after
2012 Jul 27
1
Understanding the intercept value in a multiple linear regression with categorical values
Hi!
I'm failing to understand the value of the intercept value in a
multiple linear regression with categorical values. Taking the
"warpbreaks" data set as an example, when I do:
> lm(breaks ~ wool, data=warpbreaks)
Call:
lm(formula = breaks ~ wool, data = warpbreaks)
Coefficients:
(Intercept) woolB
31.037 -5.778
I'm able to understand that the value of
2010 May 18
2
how to select rows per subset in a data frame that are max. w.r.t. a column
Hi,
I'd like to select one row in a data frame per subset which is maximal for a
particular value. I'm pretty close to the solution in the sense that I can
easily select the maximal values per subset using "aggregate", but I can't
really figure out how to select the rows in the original data frame that are
associated with these maximal values.
library(stats)
# this
2009 Nov 23
3
FUN argument to return a vector in aggregate function
Hi All,
I am currently doing the following to compute summary statistics of
aggregated data:
a = aggregate(warpbreaks$breaks, warpbreaks[,-1], mean)
b = aggregate(warpbreaks$breaks, warpbreaks[,-1], sum)
c = aggregate(warpbreaks$breaks, warpbreaks[,-1], length)
ans = cbind(a, b[,3], c[,3])
This seems unnecessarily complex to me so I tried
> aggregate(warpbreaks$breaks, warpbreaks[,-1],
2006 Apr 25
1
by() and CrossTable()
I am attempting to produce crosstabulations between two variables for
subgroups defined by a third factor variable. I'm using by() and
CrossTable() in package gmodels. I get the printing of the tables first
and then a printing of each level of the INDICES. For example:
library(gmodels)
by(warpbreaks, warpbreaks$tension, function(x){CrossTable(x$wool,
x$breaks > 30,
2007 Aug 08
1
Change in R**2 for block entry regression
Hi all,
I'm demonstrating a block entry regression using R for my regression
class. For each block, I get the R**2 and the associated F. I do this
with separate regressions adding the next block in and then get the
results by writing separate summary() statements for each regression.
Is there a more convenient way to do this and also to get the change in
R**2 and associated F test for
2008 Sep 12
2
Newbie: 'table' output in columns rather than matrix
Hi,
Coming to R from SAS...
I have a data.frame A with 2 long factors "x" and "y". I want to get
a count of the number of rows with each level of "x" and "y" jointly.
'table' seemed like it would work, but as I have many levels, the
matrix output is pretty useless to me (and I don't care about zero
values). How can I get output that looks
2016 Feb 05
2
[PATCHv2] inspect: get windows drive letters for GPT disks.
This patch updates the guestfs_inspect_get_drive_mappings API call to
also return drive letters for GPT paritions. Previously this worked
only for MBR partitions. This is achieved by matching the GPT partition
GUID with the info stored in the blob from
HKLM\SYSTEM\MountedDevices\DosDevices keys. For GPT partions this blob
contains a "DMIO:ID:" prefix followed by a 16 byte binary GUID.