[R] Weighted SD

[David Winsemius]

On Feb 1, 2010, at 3:32 PM, Thomas Lumley wrote:

> On Mon, 1 Feb 2010, David Winsemius wrote:
>
>>
>> On Feb 1, 2010, at 12:37 PM, Антон Морковин wrote:
>>
>>> Dear all,
>>> what function can be used to calculate weighted SD or/and SE¿
>>>
>>> There's no such stuff in 'base' package.
>>
>> Seems as though lm with a weights argument could be used fairly  
>> simply.
>>
>
> As I have pointed out from time to time, it depends on what the  
> weights are for -- are they precision weights, which lm() can  
> handle, or sampling weights, which it can't?

I'm looking forward to your book being released.


>
>     -tomas
>
> Thomas Lumley			Assoc. Professor, Biostatistics
> tlumley at u.washington.edu	University of Washington, Seattle

David Winsemius, MD
Heritage Laboratories
West Hartford, CT