Displaying 6 results from an estimated 6 matches for "balshaw".
2006 May 20
2
Function as.Date leading to error implying that strptime requires 3 arguments
I'm using R V 2.2.1. When I try an example from the as.Date help page,
I get an error.
> x <- c("1jan1960", "2jan1960", "31mar1960", "30jul1960")
> z <- as.Date(x, "%d%b%Y")
Error in strptime(x, format) : 2 arguments passed to 'strptime' which
requires 3
>
Any suggestions would be appreciated.
Thanks,
Rob
2003 Jan 20
2
Adding reference lines to xyplot
...ay to say I want my
reference lines to change for different visits.
I've a feeling that the subscripts arguement is somehow involved, but I've
not found any examples or references to this.
Any suggestions? Which page of the various manuals did I skim too quickly?
Thanks,
Rob
-- Robert Balshaw, Ph.D.
-- Senior Biostatistician, Syreon Corp.
-- Phone: 604.676.5900x220; Fax: 604.676.5911
2004 Dec 15
0
Re: [S] using Hmisc and Design library
sorry, I had a typo there, it's datadist(b) for the
analysis of data frame "b".
--- Robert Balshaw <Robert.Balshaw at syreon.com> wrote:
> Not sure if this will help, but did you mean to use
> datadist(a) for
> the analysis of B?
>
> Rob
>
> > -----Original Message-----
> > From: r-help-bounces at stat.math.ethz.ch
> > [mailto:r-help-bounces at stat.m...
2002 Oct 09
1
Summary Orthogonal Polynomials
As usual, the R newsgroup set me straight (thanks to Douglas Bates, Robert
Balshaw and Albyn Jones).
There is really no difference between using orthogonal polynomials of the
form:
Linear -3 -1 1 3
Quadratic 1 -1 -1 1
Cubic -1 3 -3 1
Versus
> poly(c(1:4),3)
1 2 3
[1,] -0.6708204 0.5 -0.2236068
[2,] -0.2236068 -0.5 0.6708204...
2003 Oct 21
0
summary of "explaining curious results of aov"
...error rate, but even if I did all
> 15 comparisons of the 6 groups, the Bonferroni correction to a 5%
> alpha is 0.003, yet the Bonferroni correction gives conservative
> rejection levels.
>
> How can such a result occur? Any clues would be helpful.
Brian Ripley, Robert Balshaw, Peter Dalgaard and Ted Harding all
responded. The answer was basically the same from all: If there is
heterogeneity of variances between the groups, and the variances of
groups 5 and 6 are smaller than the others, then my result could occur
because the average within-group variance over all grou...
2005 Jan 13
2
subsetting like in SAS
Hi,
Being in the process of translating some of my SAS programs to R, I
encountered one difficulty. I have a solution, but it is not elegant
(and not pleasant to implement).
I have a large dataset with many variables needed to identify the
origin of a sample, many to describe sample characteristics, others to
describe site characteristics.
I want only a (shorter) list of sites and their