[R] Quantile regression with large number of fixed effects

[C.Steinwender at lse.ac.uk]

Dear R users, 

I am trying to estimate a median regression with fixed effects. I have an unbalanced panel data set with 5,000 individuals and 10 years, resulting in a total of 20,000 observations.

When I try to add individual (firmid) fixed effects to the quantile regression using the following command:
result<-rq(y~x+factor(firmid),tau=0.5)

I get the following error message: 
"Error: cannot allocate vector of size 536.9 Mb"

I assume this has to do with the large number of fixed effects (because it worked when I only used year fixed effects). I have already set the memory to the (I believe) maximum limit using 
memory.limit(4000)

What can I do to implement this regression in R? 

Many thanks in advance,

Claudia

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