Administrative

• Present: Lee, Tom (scribe), Tim, Karthik (remote), Bill (remote)
• Tom will practice GECCO talk next week
• Frode should send us GECCO slides shortly

Plush genomes -> Push programs

• Do we want any Push program to be able to be represented by a Plush genome?
  • Lee: Yes!
  • Tom: Maybe?
• To do so, we have new instructions:
  • meta_open – opens new paren
  • meta_splice_backward – deleted previous paren pair

Hill-climbing vs. Genetic Operators

• e.g. simplification, epigenetics, etc.
• Is it useful to test and revert (using a fitness evaluation), or is just making the change and letting selection work it out just as good?
• Maybe Bill or Tom should experiment with this — EHC vs. using epigenetic genetic operators with more generations to make up for EHC’s extra evaluations.
• Simplest is to never do hill climbing, just have genetic operators.
• Decision: Implement a wrapper argument (like :make-reverting) that can be used in genetic operator pipelines that cases the next operator to be reverted if not better than its input program.

Issue of what to do with child programs that exceed size limits

Decision: implement argument with these options:

• return clone of one parent (default, as previously)
• return empty program
• return random program
• return one parent with some part(s) deleted