Optimality Constraint Archive

Welcome to the Optimality Constraint Archive. There are only a few example constraints right now, pending translation of more from existing Lisp code.

Right now you can do a little Recursive Constraint Demotion, or some T-Order Generation. If neither of these is interesting, you can browse the current constraints below. Someday this whole system will become a freely editable wiki so people can add their own constraints and definitions. In the meantime, what appears to be a database is actually just gleaned from code, but you are welcome to mail patches to ncsander@indiana.edu

Constraints

Onset

Useful in Analysis Of	Syllables
Name	Onset
Description	All syllables must have an onset

Max-IO

Superset Of	Max-IO<Segment>, Max-IO<Feature>
See Also	Max-BR, other OO constraints
Subset Of	Max
Name	Max-IO
Description	Every segment in the input must appear in the output

*Low

Denigrated By	Basically Everybody
Framework	Shameless Ad Hockery
Name	*Low
Proposed By	Sanders (20x6)
Description	This is a fake constraint necessary for the fake test of RCD I am using. A better example following McCarthy's Thematic Guide is soon coming.

Dep-IO

Superset Of	Dep-IO<Segment>, Dep-IO<Feature>
Subset Of	Dep
Name	Dep-IO
Description	Every segment in the output must appear in the input

OCP-Coronal

Denigrated By	Other Person (1998a) (1998b) (1998c)
Framework	Classic OT, others
Name	OCP-Coronal
Proposed By	Placeholder (1997)
Description	Prevent two coronals from occurring next to each other

Note: the Name field should really be HTML Name; there are (ideally) three names for each constraint: code name, HTML name and LaTeX name.

Source

The source for this site is released under the GPL, except for the utility library, which is released under the revised BSD licence. What this means is that you may copy and distribute the code, and use it in new programs as long as they include the source code. You can do whatever you want with the utilities.

mark.py – the markedness constraints
faith.py – the faithfulness constraints
constraints.py – index constraints in various ways

rcd.py – recursive constraint demotion
otutils.py – ot-specific utilities
TODO: Switch everything over to UTF-8 so that IPA can be used.
TODO: Make the code available via darcs or some other version control system.

The formal constraint definitions are Python functions that return the number of violations incurred, from 0 to infinity. It is possible to return a negative number, but this is an error, at least in classic OT. The metadata about each constraint is stored as key=value pairs in the docstring, but this is not really scalable and will probably be replaced by a database soon. In particular, the proper setup would allow a wiki to interface with the constraint database so anyone could add constraints.