For those who don’t feel like running the numbers, “I don’t know” is the best option when you think the probability of your answer being correct is between 20% and 33%, “low confidence” is the best when you think the probability is between 33% and 60%, and “high confidence” is the best when you think the probability is between 60% and 100%.
If your probability doesn’t fall between 20% and 100%, you’re doing something wrong.
For true/false questions, you can’t think the probability of your answer being correct is less than 50%. If you did think that, it wouldn’t be your answer.
For those who don’t feel like running the numbers, “I don’t know” is the best option when you think the probability of your answer being correct is between 20% and 33%, “low confidence” is the best when you think the probability is between 33% and 60%, and “high confidence” is the best when you think the probability is between 60% and 100%.
If your probability doesn’t fall between 20% and 100%, you’re doing something wrong.
For true/false questions, you can’t think the probability of your answer being correct is less than 50%. If you did think that, it wouldn’t be your answer.