Just-Pope production functions with Heckman selectivity correction.
JPselection is an R package that implements the three-step estimation procedure of Koundouri & Nauges (2005, Journal of Agricultural and Resource Economics 30(3):597-608) for Just-Pope (1978, 1979) stochastic production functions with sample-selection bias from crop choice.
The package returns the corrected and uncorrected specifications side by side, so the bias in risk-function coefficients, the headline finding of the paper, is visible directly.
Where to go next
-
Get started — a runnable example from simulated data to final tables, with sample
print(),summary(), andplot()output. - Methodology — the Just-Pope framework, the Heckman correction, the three estimation steps, and alternative mean and risk functional forms.
- Function reference — every exported function grouped by role (full pipeline, S3 methods, individual stages, export, example data).
Citation
If you use JPselection in published work, please cite the underlying paper together with the package:
Koundouri, P. and Nauges, C. (2005). On Production Function Estimation with Selectivity and Risk Considerations. Journal of Agricultural and Resource Economics, 30(3), 597-608.
Cardenas Retamal, R. (2026). JPselection: Just-Pope Production Functions with Heckman Selectivity Correction. R package version 0.2.0. https://github.com/robcareta/JPselection
In R, the canonical citation is also available via citation("JPselection").
References
- Heckman, J. (1979). Sample selection bias as a specification error. Econometrica, 47, 153-161.
- Just, R. E. and Pope, R. D. (1978). Stochastic representation of production functions and econometric implications. Journal of Econometrics, 7, 67-86.
- Koundouri, P. and Nauges, C. (2005). On Production Function Estimation with Selectivity and Risk Considerations. Journal of Agricultural and Resource Economics, 30(3), 597-608.