I need to do a stochastic frontier of a translogarithmic regression. So I used the translogEst function with the data (name "Data") beneath. At the bottom of the code you can see the sfa() I did.
X; BankName; Year; Labor; PhysicalCapital; Loans; Deposits; TotalCosts; TCPK; PLPK
1; "HSBC" ; 2002; 0.123; 2.19; 1200; 3200; 10.9; 4.9; 0.00089
estTranslog <- translogEst("TCPK", c("Loans","Deposits", "PLPK", "Loans", "Deposits"), data = Data, shifterNames = NULL, dataLogged = FALSE)
sfaData <- sfa( estTranslog$est
, data = Data, ineffDecrease = TRUE, truncNorm = TRUE, timeEffect = FALSE, startVal = NULL
, tol = 0.00001, maxit = 1000, muBound = 2, bignum = 1.0E+16, searchStep = 0.00001, searchTol = 0.001
, searchScale = NA, gridSize = 0.1, gridDouble = TRUE, restartMax = 10, restartFactor = 0.999, printIter = 0)
**Value of estTranslog$est**
Call:
lm(formula = as.formula(estFormula), data = estData)
Coefficients:
(Intercept) a_1 a_2 a_3 a_4 a_5 b_1_1 b_1_2
2.683958 0.161657 -0.020009 0.499711 NA NA -0.024701 0.022882
b_1_3 b_1_4 b_1_5 b_2_2 b_2_3 b_2_4 b_2_5 b_3_3
0.001178 NA NA 0.064574 -0.019852 NA NA -0.075377
When I run the translogEst function, no problem occurs. But when I run the sfa() the following error appears:
Error in eval(expr, envir, enclos) : object 'y' not found.
This while estTranslog$est returns a lm function and the y variable of this regression can be found in the Data.
How can I fix this error?