similar to: Standard error of a sum

Displaying 20 results from an estimated 1000 matches similar to: "Standard error of a sum"

2012 Aug 07
3
NADA Package: Referencing Data Frame Columns
The sample data sets that come with the NADA package are limited to one or two variables and a censored measurement indicator column. I try to mimic examples using my data but keep missing the target. My water chemistry data is available in two formats: long (as seen in a database table) and wide (as seen in a spreadsheet). The two structures are: str(chem) 'data.frame': 65349 obs. of
2012 Aug 07
3
reshape2's dcast() Adds NAs to Data Frame
I need to understand how and why dcast() adds NAs to a data frame that contained no missing values. The database table of chemical concentrations has all missing values removed because they cannot contribute to data analyses. The structure of the R data frame of these data have no NA values, and neither does the data frame resulting from applying the reshape2 melt() function to it. However,
2012 Jul 10
2
Understanding cenros Error
Before reading water chemistry into a data frame I removed all missing data. Yet when I try to run cenros() to summarize a specific chemical I get an error that I do not understand: with( subset(chem, param=='Ag'), cenros(quant,ceneq1) ) Error in lm.fit(x, y, offset = offset, singular.ok = singular.ok, ...) : NA/NaN/Inf in 'y' I would like to learn what I did incorrectly
2007 Nov 08
2
a newbie question about "data"
hi, I am reading Modern Applied Statistics with S 4th ed$B!#(B page4 have these two lines: > library(MASS) > data(chem) # needed in R only but I find withou the line " data(chem)" I can still access chem, isn't it? is it unnecessary or something i missed here? thanks for the replay in advance.
2004 Nov 11
5
expressions and paste
I have written a function to plot data which will be used for various different chemistries. A simplified version is: plot_data <- function(risk,levels,chem,sd2,measure){ plot(risk, levels,main=paste ("per", sd2, measure, "\n in usual", chem)) } The problem is with the title. This works fine if the variable "chem" is just text, but if it is an expression then
2008 Oct 29
2
call works with gee and yags, but not geepack
I have included data at the bottom of this email. It can be read in by highlighting the data and then using this command: dat <- read.table("clipboard", header = TRUE,sep="\t") I can obtain solutions with both of these: library(gee) fit.gee<-gee(score ~ chem + time, id=id, family=gaussian,corstr="exchangeable",data=dat) and library(yags) fit.yags <-
2017 Sep 25
3
rkward_0.6.5-1~stretchcran.0_amd64.deb missing
Hello Johannes: I'm sorry, but I still have the same problem with Rkward. After running apt-get update, I still can not find the amd64 version of the Rkward package. I have tried it with the following sources: deb http://cran.r-project.org/bin/linux/debian stretch-cran34/ deb http://chem.uft.uni-bremen.de/ranke/r-cran stretch-cran34/ deb
2017 Sep 26
2
rkward_0.6.5-1~stretchcran.0_amd64.deb missing
Hi Johannes: Thank you very much. Rkward now works. The only drawback is that I had to install it "by hand": sudo dpkg -i rkward_0.6.5-1~stretchcran.0_amd64.deb rkward-data_0.6.5-1~stretchcran.0_all.deb By default, apt-get installed the Debian repository version (rkward 0.6.5-1+b1 0.6.5-1+b1). Thanks for your contributions to the R-Debian project! Regards. Griera. On Mon, 25
2012 Jul 05
1
reshape2 errors on data frame
I've successfully reformatted data frames from long to wide with reshape2, but this time I'm getting errors that I want to understand and resolve. Here's the data frame structure and the results of the melt() and dcast() functions: str(waterchem) 'data.frame': 128412 obs. of 8 variables: $ site : Factor w/ 64 levels "D-1","D-2","D-3",..: 1 1
2007 Aug 30
1
categorical variable coefficients in QSAR
Dear list: I am interested in the following sort of problem, as is found frequently in the field of QSAR. I have biological activity as a function of chemical structure, with structure defined in a categorical manner in that the SUBSTITUENT is the levels of the POSITION factor. For example, data from Kubinyi (http://www.kubinyi.de/dd-12.pdf) for this type of analysis is presented as follows:
2008 Sep 15
4
How to draw a plot like this?
Hi there, I hope to draw a plot like this: http://www.sg-chem.net/swizard/Ru-bqdi-spectra.gif is it possible to draw it using R? thanks for any suggestions. regards, Jinsong
2003 Jul 10
6
info
HI I'm a student in chemical engineering, and i have to implement an algoritm about FIVE PARAMETERS INTERPOLATION for a calibration curve (dose, optical density) y = a + (c - a) /(1+ e[-b(x-m]) where x = ln(analyte dose + 1) y = the optical absorbance data a = the curves top asymptote b = the slope of the curve c = the curves bottom asymptote m = the curve X intercept Have you never seen
2007 Dec 06
1
finding most highly transcribed genes - ranking, sorting and subsets?
Hello, I am not only interested in finding out which genes are the most highly up- or down-regulated (which I have done using the linear models and Bayesian statistics in Limma), but I also want to know which genes are consistently highly transcribed (ie. they have a high intensity in the channel of interest eg. Cy5 or Cy3 across the set of experiments). I might have missed a straight forward
2003 Jul 10
2
XML Package.
Hi! I have installed the new R on windows. I wanted to reinstall the XML package. I am not able to find the XML.zip anymore. I am quite shure that they where a windows binary version. Has anyone old XML windows binary? Eryk Dipl. bio-chem. Eryk Witold Wolski @ MPI-MG Dep. Vertebrate Genomics Ihnestrasse 73 14195 Berlin 'v' tel: 0049-30-84131285 / \ mail:
2004 Apr 30
2
./configure --prefix and R_LIBS
Hi! I am installing R in non standard directory. ./configure --prefix=/non/standard/directory The installation works fine. But after starting R i get .libPaths() /usr/lib/R/library but they cant be there of course! Have I to set some additional switches during config? Eryk Dipl. bio-chem. Eryk Witold Wolski @ MPI-Moleculare Genetic Ihnestrasse 63-73 14195 Berlin 'v' tel:
2013 Sep 01
2
string processing(regular expressions)
I have a variable that is course # nCourse <- as.factor(c("002A","002B","002C","007A","007B","007C","101","118A","118B","118C")) And I would like to get rid of the leading zeros, and have the following set
2015 Jun 17
2
selinux allow apache log access
> > What turns up in myzabbix.te? Same deal. :( #semodule -i myzabbix.te semodule: Failed on myzabbix.te! sigh... but thanks any other clues? On Wed, Jun 17, 2015 at 11:42 AM, Harold Toms <h.toms at qmul.ac.uk> wrote: > On 17/06/15 16:29, Tim Dunphy wrote: > >> That's because there's already a zabbix module loaded (the message isn't >>> very
2015 Jun 17
2
selinux allow apache log access
> > That's because there's already a zabbix module loaded (the message isn't > very informative!). I forgot that the received wisdom is to insert "my" in > front of ones own modules i.e.: > grep zabbix /var/log/audit/audit.log | audit2allow -M myzabbix > semodule -i myzabbix.pp Hmm no luck there either: [root at monitor2:~] #semodule -i myzabbix.pp
2003 Nov 21
2
method names conflict.
Hi! I would like to give my objects functions like "subset", "union", et cetera and name it also in this way. But this functions names are already used in the base package and they are not generic. I am right in that if they would be generic then i still can use the neat names with my objects? I have the impression that there are more and more packages are going to be
2010 May 06
4
Samba/LDAP share issue -- user with invalid SID
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Greetings, While I've seen this referred to a lot of places, I haven't yet found a posted solution that works for me. Testing has been done from a Mac running OSX 10.5.8 Here's what I have so far: if anyone can give me a next step to test, I'd appreciate it. If anyone can give me a complete solution, I'd appreciate it even