Arbitrary PRO

Arbitrary PRO refers to instance of PRO which is not controlled and has arbitrary reference.

Example

In the sentence the PRO subject of to sit is not controlled and has the same arbitrary meaning as one in that one just sits there should be forbidden.

Just PRO to sit there should be forbidden.

Link

Utrecht Lexicon of Linguistics

References

Chomsky, Noam A. 1981. Lectures on Government and Binding. Dordrecht:Foris.