Displaying 13 results from an estimated 13 matches similar to: "How to formulate an (effect-modifying) interaction with matching variable in a conditional logistic regression?"
2006 Jul 07
2
Multistage Sampling
Dear WizaRds, dear Thomas,
First of all, I want to tell you how grateful I am for all your
support. I wish I will be able to help others along one day the same way
you do. Thank you so much. I am struggling with a multistage sampling
design:
library(survey)
multi3 <- data.frame(cluster=c(1,1,1,1 ,2,2,2, 3,3), id=c(1,2,3,4,
1,2,3, 1,2),
nl=c(4,4,4,4, 3,3,3, 2,2), Nl=c(100,100,100,100,
2003 Oct 02
0
Doubly Multivariate LME
Dear R:
I am trying to fit a doubly multivariate LME (DM) where I have two response variables measured on two occasions per person. Specifically, reading and math scores measured at the beginning and ending of a school year. The response variables have a correlation of r = .85.
The response variables in the data matrix are stacked in a vector with a dummy code flagging each outcome and with
2007 Nov 16
1
constraint matrices in vglm (VGAM package)
Hello R users,
I am performing a multinomial logit regression and would like to
constrain a few model coefficients to be equal.
Here is my model:
multi <- vglm(case123con ~ SNP_A1+SNP_A2+age, multinomial, work.analy)
where case123con is a four level categorical variable (case 1, case 2,
case 3, control) and SNP_A1 and SNP_A2 are indicator functions (yes/no).
The output of this
2013 Oct 31
3
[releng_10 tinderbox] failure on i386/pc98
TB --- 2013-10-31 19:50:43 - tinderbox 2.20 running on worker01.tb.des.no
TB --- 2013-10-31 19:50:43 - FreeBSD worker01.tb.des.no 9.1-RELEASE-p4 FreeBSD 9.1-RELEASE-p4 #0: Mon Jun 17 11:42:37 UTC 2013 root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC amd64
TB --- 2013-10-31 19:50:43 - starting RELENG_10 tinderbox run for i386/pc98
TB --- 2013-10-31 19:50:43 - cleaning the
2002 Dec 04
1
R-Winedt
Hello:
I installed R-WinEdit according to the instructions, including those for
setting
the editor and pager options. Doesn''t seem to work--when I try to edit a
file, I get the following:
> > options(editor="\"c:/program files/winedt/winedt\" -c=\"R-WinEdt-edit\"
> -e=r.ini -V")
> > getOption("editor")
>[1]
2013 Sep 12
25
shorewall-lite error at start
Hi,
My main gateway is a router running on OpenWrt Barrier Breaker
r37816/ Kernel Version3.10.4.
I installed shorewall-lite from openwrt''s repo using opkg but while
trying to start shorewall-lite I get the folowing errors:
The first error i got was "scp: /var/lib/shorewall-lite: No such file
or directory" simply resolved by making the folder "shorewall-lite"
2017 Jul 12
0
How to formulate quadratic function with interaction terms for the PLS fitting model?
Dear all,
I am using the pls package of R to perform partial least square on a set of
multivariate data. Instead of fitting a linear model, I want to fit my
data with a quadratic function with interaction terms. But I am not sure
how. I will use an example to illustrate my problem:
Following the example in the PLS manual:
## Read data
data(gasoline)
gasTrain <- gasoline[1:50,]
## Perform
2010 Dec 06
1
How to formulate constraint like abs(x) = y in constrOptim (or other)
Hello list reader,
I am trying to form some constraints for an optimization I am working on.
I think I have understand the use of the constraints in matrix form. I use
them like:
constr_mat<- -diag(2)
constr_vec<- rep(-0.05,2)
constr_mat<- rbind(constr_mat, diag(2))
constr_vec<- c(constr_vec, rep(-1, 2))
To get parameters in the interval [-1, 0.05]. (And this works so far)
Now I
2017 Jul 13
0
How to formulate quadratic function with interaction terms for the PLS fitting model?
Below.
-- Bert
Bert Gunter
On Thu, Jul 13, 2017 at 3:07 AM, Luigi Biagini <luigi.biagini at gmail.com> wrote:
> I have two ideas about it.
>
> 1-
> i) Entering variables in quadratic form is done with the command I
> (variable ^ 2) -
> plsr (octane ~ NIR + I (nir ^ 2), ncomp = 10, data = gasTrain, validation =
> "LOO"
> You could also use a new variable
2017 Jul 13
3
How to formulate quadratic function with interaction terms for the PLS fitting model?
I have two ideas about it.
1-
i) Entering variables in quadratic form is done with the command I
(variable ^ 2) -
plsr (octane ~ NIR + I (nir ^ 2), ncomp = 10, data = gasTrain, validation =
"LOO"
You could also use a new variable NIR_sq <- (NIR) ^ 2
ii) To insert a square variable, use syntax I (x ^ 2) - it is very
important to insert I before the parentheses.
iii) If you want to
2017 Jul 16
0
How to formulate quadratic function with interaction terms for the PLS fitting model?
??
If I haven't misunderstood, they are completely different!
1) NIR must be a matrix, or poly(NIR,...) will fail.
2) Due to the previously identified bug in poly, degree must be
explicitly given as poly(NIR, degree =2,raw = TRUE).
Now consider the following example:
> df <-matrix(runif(60),ncol=3)
> y <- runif(20)
> mdl1 <-lm(y~df*I(df^2))
> mdl2
2017 Jul 16
2
How to formulate quadratic function with interaction terms for the PLS fitting model?
> On Jul 13, 2017, at 7:43 AM, Bert Gunter <bgunter.4567 at gmail.com> wrote:
>
> Below.
>
> -- Bert
> Bert Gunter
>
>
>
> On Thu, Jul 13, 2017 at 3:07 AM, Luigi Biagini <luigi.biagini at gmail.com> wrote:
>> I have two ideas about it.
>>
>> 1-
>> i) Entering variables in quadratic form is done with the command I
>>
2008 Jul 12
1
Reading Multi-value data fields for descriptive analysis
Hello,
I'm looking for help on the best approach to get "multi-value" data fields into R for simple descriptive analysis.
-------------------------------------
I am new to this list and new to R, but I really want to get over the hump and get productive with it. Some help with how to best get the following data into R would be greatly appreciated. I have programming experience