summary.semsfa: Summary for 'semsfa' object In semsfa: Semiparametric Estimation of Stochastic Frontier Models

Description

Create and print summary results of a stochastic frontier model object returned by `semsfa()` with regard to the "CONDITIONAL EXPECTATION ESTIMATE" of the first step and to the "VARIANCE COMPONENTS ESTIMATE" of the compound error.

Usage

 ```1 2``` ```## S3 method for class 'semsfa' summary(object, ...) ```

Arguments

 `object` an `semsfa` object returned by semsfa() `...` further arguments to the summary method are currently ignored

Details

Please note that if bootstrap is carried out the t-statistic is not reliable for testing the statistical significance of σ and λ, because these parameters are censored and cannot follow a t-distribution. We suggest to compare the BIC of the semiparametric estimated model with the base model.

Value

`summary.semsfa` returns the summary of an object returned by `semsfa()` with few modifications if bootstrap is carried out:

 `b.t` t-statistic given the bootstrapped standard errors for λ and σ (`b.se`) `b.pv` p-values of the t-statistic

Note

`summary` returns the same result if applied to an object created with `semsfa` or `efficiencies.semsfa`

Author(s)

Giancarlo Ferrara and Francesco Vidoli

`semsfa`, `efficiencies.semsfa`
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22``` ``` #generate data set.seed(0) n<-200 x<- runif(n, 1, 2) fy<- 2+30*x-5*x^2 v<- rnorm(n, 0, 1) u<- abs(rnorm(n,0,2.5)) #production frontier y <- fy + v - u dati<-data.frame(y,x) #first-step: gam, second-step: fan (default) #without bootstrap o<-semsfa(y~s(x),dati,sem.method="gam") summary(o) # ... with bootstrap o<-semsfa(y~s(x),dati,sem.method="gam",n.boot=100) summary(o) ```