Self-grading vs. machine-grading in spaced repetition memory systems

In a Spaced repetition memory system, the key input to the control system is: did the user remember the prompt correctly? Some systems are self-graded: the user indicates whether they remembered or not. Others ask the user to input the answer; then the system computes whether the user was correct.

Self-graded systems outperform machine-graded systems in most respects.

• Advantages of self-graded systems
  • Self-graded spaced repetition memory systems are more efficient than machine-graded systems
  • Self-graded spaced repetition memory systems avoid false negatives
  • Self-graded spaced repetition memory systems accommodate a wider variety of prompts
• Advantages of machine-graded systems
  • Machine-graded spaced repetition memory systems can perform more advanced knowledge modeling
• To what extent do people “lie” when self-grading spaced repetition prompts?
• Is overt retrieval practice more effective than covert?

Interestingly, Commercially-successful spaced repetition memory systems are all machine-graded