eff, efficiencies {Benchmarking} R Documentation

## Calculate efficiencies for Farrell and sfa object

### Description

Calculate efficiencies for Farrell and sfa object. For a sfa there are several types

### Usage

```eff( object, ... )
efficiencies( object, ... )
## Default S3 method:
efficiencies( object, ... )
## S3 method for class 'Farrell'
efficiencies(object, type = "Farrell", ...)
## S3 method for class 'Farrell'
eff(object, type = "Farrell", ...)
## S3 method for class 'sfa'
efficiencies(object, type = "BC", ...)
## S3 method for class 'sfa'
eff(object, type = "BC", ...)
```

### Arguments

 `object` A Farrell object returned from a DEA function like dea, sdea, or mea or an sfa object returned from the function sfa. `type` The type of efficiencies to be calculated. For a Farrell object the possibilities are “Farrell” efficiency or “Shephard” efficiency. For a sfa object the possibilities are “BC”, “Mode”, “J”, or “add”. `...` Further arguments ...

### Details

The possible types for class `Farrell` (an object returned from `dea` et al. are “Farrell” and “Shephard”.

The possible types for class `sfa` efficiencies are

BC

Efficiencies estimated by minimizing the mean square error; Eq. (7.21) in Bogetoft and Otto (2011, 219) and Battese and Coelli (1988, 392)

Mode

Efficiencies estimates using the conditional mode approach; Bogetoft and Otto (2011, 219), Jondrow et al. (1982, 235).

J

Efficiencies estimates using the conditional mean approach Jondrow et al. (1982, 235).

Efficiency in the additive model, Bogetoft and Otto (2011, 219)

### Value

The efficiencies are returned as an array.

### Note

For the Farrell object the orientation is determined by the calculations that led to the object and can not be changed here.

### Author(s)

Peter Bogetoft and Lars Otto larsot23@gmail.com

### References

Bogetoft and Otto; Benchmarking with DEA, SFA, and R, Springer 2011

`dea` and `sfa`.
```##---- Should be DIRECTLY executable !! ----