I have never taken a statistics class nor read a statistics text, but
I am in dire need of help with a trivial data analysis problem for
which I need to write a report in two hours. I have spent 10,000
hours of study in my field of expertise (high frequency noise-making
plant biology) but I've
On 01-Apr-06 Frank E Harrell Jr wrote:
I have never taken a statistics class nor read a statistics text, but
I am in dire need of help with a trivial data analysis problem for
which I need to write a report in two hours. I have spent 10,000
hours of study in my field of expertise (high
Oh, and I forgot to add. Please generate some test data for me since
I can't possibly take time out to provide such in order to clarify the
question. By the way, I did try out R a bit but it did not work and its
too much effort to provide the R code I have or to reduce it to a small
self
I wish to perform brain surgery this afternoon at 4pm and don't know
where to start. My background is the history of great statistician
sports legends but I am willing to learn. I know there are courses and
numerous books on brain surgery but I don't have the time for those.
Please direct me
On Fri, 1 Apr 2005, Frank E Harrell Jr wrote:
I wish to perform brain surgery this afternoon at 4pm and don't know
where to start. My background is the history of great statistician
sports legends but I am willing to learn. I know there are courses and
numerous books on brain surgery but I
Ben wrote:
I wish to perform brain surgery this afternoon at 4pm and don't know
where to start. My background is the history of great statistician
sports legends but I am willing to learn. I know there are courses and
numerous books on brain surgery but I don't have the time for those.
...
It
Hi
On 11 Nov 2004 at 12:24, Drew Hoysak wrote:
I am experiencing strange (to me) output when trying to do simple
calculations. Expressions that should equal zero yield non-zero
values. Examples:
a - 4.1-3.1
b - 5.1-4.1
a-b
[1] -4.440892e-16
(4.1-3.1)-(5.1-4.1)
[1]
I am experiencing strange (to me) output when trying to do simple
calculations. Expressions that should equal zero yield non-zero
values.
Examples:
a - 4.1-3.1
b - 5.1-4.1
a-b
[1] -4.440892e-16
(4.1-3.1)-(5.1-4.1)
[1] -4.440892e-16
When this last expression is expanded, I get the right
Drew Hoysak [EMAIL PROTECTED] writes:
I am experiencing strange (to me) output when trying to do simple
calculations. Expressions that should equal zero yield non-zero
values.
Examples:
a - 4.1-3.1
b - 5.1-4.1
a-b
[1] -4.440892e-16
(4.1-3.1)-(5.1-4.1)
[1] -4.440892e-16
On Thu, 11 Nov 2004, Drew Hoysak wrote:
I am experiencing strange (to me) output when trying to do simple
calculations. Expressions that should equal zero yield non-zero
values.
No. There is no reason why these expressions should yield zero values.
Remember that computers work in base 2, and
R does double precision arithmetic and accumulates roundoff error
like any other double precision computations. I would therefore expect
it to accumulate roundoff error as you have reported. In most cases
like you mentioned, a difference of 4e-16 is not material, to use
Accounting
On Thu, 2004-11-11 at 12:24 -0500, Drew Hoysak wrote:
I am experiencing strange (to me) output when trying to do simple
calculations. Expressions that should equal zero yield non-zero
values.
Examples:
a - 4.1-3.1
b - 5.1-4.1
a-b
[1] -4.440892e-16
(4.1-3.1)-(5.1-4.1)
[1]
12 matches
Mail list logo
