[R] force glm estimates to be nonnegative

[Samu Mäntyniemi]

You could use the BRugs package and formulate your prior knowledge about 
  slopes in terms of a probability distribution.

Michele Christina Itten kirjoitti:
> Is there a way to force certain formula parameters to be nonnegative?
> 
> What I want to do is to estimate student capacity over time, namely by
> 
>>  capacity ~ Student + Student:Day
> 
> I add this formula to a glm call and obtain negative learning slope estimates (Student:Day) in some cases. 
> However, I don't want to allow for that. In such a case, glm should solve 
> 
>> capacity ~ Student
> 
> and I will set the slope to zero. 
> 
> Is there an option to constrain a parameter set to nonnegative values?
> 
> 
> 
> 
> Many thanks in advance!
> 
> Michele Itten,
> BS. Carnegie Mellon
> 
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> and provide commented, minimal, self-contained, reproducible code.
> 
> 


-- 
------------------------------------------
Samu Mäntyniemi
Researcher
Fisheries and Environmental Management Group (FEM)
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