Hello,
I wish to calculate a figure where I call coefficient estimates and
residuals sum of squares and degrees of freedom. All these quantities are
from the stata estimation output. When I run the relevant command "nlcom
exp(_b[_cons]+_b[income]*15.3)*exp(e(rss)/e(df_r)/2)" I get the error "could
not calculate numerical derivative". This is perhaps because e(rss) and
e(df_r) are not estimates. (As Maarten pointed out yesterday actually)
1. Does this mean that in the nlcom command I am only allowed to specify
coefficient estimates? 
2. How can I achieve what I want to achieve: I wish to call figures into the
stated command I am running. 
Thanks in advance. 
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