Re: [R] Problem with Weighted Variance in Hmisc

2007-06-01 Thread Tom La Bone
Wonderful! Thanks for the assistance. Tom La Bone -Original Message- From: jiho [mailto:[EMAIL PROTECTED] Sent: Friday, June 01, 2007 8:17 AM To: [EMAIL PROTECTED] Cc: 'R-help' Subject: Re: [R] Problem with Weighted Variance in Hmisc On 2007-June-01 , at 13:00 , Tom La

Re: [R] Problem with Weighted Variance in Hmisc

2007-06-01 Thread Frank E Harrell Jr
jiho wrote: > On 2007-June-01 , at 01:03 , Tom La Bone wrote: >> The function wtd.var(x,w) in Hmisc calculates the weighted variance >> of x >> where w are the weights. It appears to me that wtd.var(x,w) = var >> (x) if all >> of the weights are equal, but this does not appear to be the case.

Re: [R] Problem with Weighted Variance in Hmisc

2007-06-01 Thread jiho
On 2007-June-01 , at 13:00 , Tom La Bone wrote: > The equation for weighted variance given in the NIST DataPlot > documentation > is the usual variance equation with the weights inserted. The > weighted > variance of the weighted mean is this weighted variance divided by N. > > There is anoth

Re: [R] Problem with Weighted Variance in Hmisc

2007-06-01 Thread Tom La Bone
that discusses the merits of the DataPlot approach versus the Bevington approach? Tom La Bone -Original Message- From: jiho [mailto:[EMAIL PROTECTED] Sent: Friday, June 01, 2007 2:17 AM To: [EMAIL PROTECTED]; R-help Subject: Re: [R] Problem with Weighted Variance in Hmisc On 2007-June-01 , at 0

Re: [R] Problem with Weighted Variance in Hmisc

2007-05-31 Thread jiho
On 2007-June-01 , at 01:03 , Tom La Bone wrote: > The function wtd.var(x,w) in Hmisc calculates the weighted variance > of x > where w are the weights. It appears to me that wtd.var(x,w) = var > (x) if all > of the weights are equal, but this does not appear to be the case. Can > someone point

[R] Problem with Weighted Variance in Hmisc

2007-05-31 Thread Tom La Bone
The function wtd.var(x,w) in Hmisc calculates the weighted variance of x where w are the weights. It appears to me that wtd.var(x,w) = var(x) if all of the weights are equal, but this does not appear to be the case. Can someone point out to me where I am going wrong here? Thanks. Tom La Bo