[R] Book recomendation: Repeated Measurements

Spencer Graves spencer.graves at structuremonitoring.com
Mon Jul 15 01:38:08 CEST 2013


On 7/14/2013 3:05 PM, Rolf Turner wrote:
> On 15/07/13 08:57, Spencer Graves wrote:
>
> <SNIP>
>>
>>       You may know that "mixed effects" is another term for "repeated 
>> measurements".
>
> <SNIP>
>
> I must of course preface this comment with an "I am no expert" 
> disclaimer, but I do not
> believe that this assertion is correct.  It would be more correct, I 
> believe, to say that
> repeated measurement models form a particular sub-class of mixed 
> effects models.
>
> Those who *are* experts may well correct me if I am wrong about this.


       Thanks for the clarification, Rolf.  You are absolutely correct.  
"Repeated measurements" refers to the sampling plan. "Mixed effects" 
describes a form of mathematical modeling.  There are balanced repeated 
measures data sets where people do not have to worry about the 
subtleties of mixed-effects modeling.  An experiment with multiple 
litters with several mice in at least some of the litters would call for 
mixed-effects modeling.  This would include "repeated measures" on the 
litters but not the mice.


       However, "I am no expert" on repeated measures / mixed-effects, 
either


        Spencer

>
>     cheers,
>
>         Rolf



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