What is a reasonable model for human computation (without using a paper and pencil)?
A concrete model for human computation will allow us to:
- Estimate human usability
- Count steps and prove human usability mathematically
- Assert that certain things are impossible for human computation
Humans vs. Computers
- Computers are faster in doing arithmetic operations.
- Computers keep improving in speed and memory.
- When counting steps, hidden constants are crucial (i.e. O(n) may not be good enough for humans if hidden constant c is large).
- Some problems become easy with respect to human computation. For example, factoring is a hard problem in general. However, any number calculated by a human by multiplying two equal-length primes (in head) can be factored by a laptop within seconds.
Major Open Problem: Can humans compute 1-way functions (in their head) that powerful supercomputers cannot invert?
Model of human conscious computation
Turing machine with two distinct tapes:
- Long term or permanent memory (LTM):
- Hard to write (can only be written to slowly)
- Easy to read (can be read quickly)
- Retention requires rehearsal on Wozniak’s doubling schedule
- Short term or working memory (STM):
- Easy to read and write
- Tiny in size: chunks
- Storage is fleeting: items in STM are pushed out by new deposits
- Chunks are “pointers” into memory