# Formal priors

A prior is endorsed *formally* if it has either been derived using a formal well-established rule (in the broad sense defined by ^{[1]}) like the

or if it has been deduced following formal statistical arguments like

- invariance, or
- admissibility.

## References

- ↑ Kass, R.E. and Wasserman, L. (1996), "The Selection of Prior Distributions by Formal Rules", Journal of the American Statistical Association, Vol.91, pp. 1343-1370.