Displaying 2 results from an estimated 2 matches for "effecta".
Did you mean:
effect
2006 Aug 07
2
Constrain coefs. in linear model to sum to 0
Hello!
I would like to use constrain to sum coeficients of a factor to 0 instead
of classical corner contraint i.e. I would like to fit a model like
lm(y ~ 1 + effectA + effectB)
and say get parameters
intercept
effectA_1
effectA_2
effectB_1
effectB_2
effectB_3
where effectA_1 represents deviation of level A_1 from intercept and
sum(effectA_1, effectA_2) = 0 and the same for factor B.
Is this possible to do?
Lep pozdrav / With regards,
Gregor Gorjanc
-...
2009 Jun 27
1
Regression; how to get t-values for all parameters estimates
Dear all,
Even after a couple of hours looking at old messages I still haven't found a
solution for my problem.
I'm trying to fit an additive linear regression model with 2 effects, both
fixed, to some dataset. The function contrasts(effectA) <- contr.sum can
gaurantee that the coefficients per parameter sum to one, and the function
dummy.coef provices the estimates of all coefficientss. But I would also like to
be able to obtain the corresponding t-values for ALL parameters (not just the
number of effects minus 1, provided by summa...