Tools : Mercy : Criteria dialog box can be used to determine the criteria by which items rescheduled with Tools : Mercy should be sorted.

Warning! Each time you use Mercy, you add extra hours of work to mastering the same amount of material! The extra workload comes from breaks in learning, not from Mercy itself!

If you have just returned from vacation or have suffered a lapse in will power, you will probably want to reschedule outstanding repetitions in some period of time. This way you can avoid piles of work SuperMemo kept for you in store. However, depending on the nature of the material stored in your system you might want to use completely different criteria. For example, if you have added lots of important job-related information shortly before leaving for vacation, you might want to quickly go through this recently introduced material. In other cases you might want to ease the stress related to the return to repetitions by picking the easiest material first, or boost your morale by picking most recent items and realizing how much you forfeit when neglecting repetitions. You might also want to minimize the loss to the long-term learning process by starting with elements you have invested most in or those whose repetitions have been delayed most

Here are the sorting criteria used by Mercy:

1. Importance - importance of the elements as determined by ordinal numbers and the forgetting index. Use this criterion to give priority to the material that you have marked as high-priority material
2. Lateness - degree of delay of repetitions of the elements. Usually short-interval elements are more likely to be forgotten as a result of delay. Use this criterion to minimize the forgetting rate during repetitions of the rescheduled material
3. Investment - investment of your time in memorizing the elements. The investment is determined by the number of repetitions, the number of memory lapses, and most of all, the length of the interval. Use this criterion to protect the material you have worked hardest on. Even though this is the material that is least likely to be forgotten, each memory lapse of high-investment material will result in a most painful increase in workload
4. Easiness - easiness of the elements as determined by the interval and the number of memory lapses (the fewer the lapses and the longer the interval, the easier the element). Use this criterion to maximize the speed and minimize the stress of handling the outstanding material. You can opt for maximizing Easiness in times of crisis (i.e. when you cannot devote sufficient attention to repetitions). This way you can quickly dislodge most of the outstanding material without adding many repetitions of newly forgotten elements. This way you can deal with the hardest part only then when you can see the end of hardship coming soon. Note that A-factors might be but are not used for determining Easiness
5. Recency - how recently the elements have been introduced into the learning process. The recency is determined by (1) intervals (shorter intervals indicate recency), (2) memory lapses (lapses refute recency) and (3) number of repetitions (recent items have fewer repetitions made). Use this criterion when the most recently introduced material is of highest recall priority (e.g. in cases you memorized some critical job-related material before leaving for vacation). This criterion is also very useful if you are going through a crisis with your repetition (Do I really need to spend that much time with SuperMemo?). Recency criterion will help you quickly realize what great stuff you have learned recently and what a pity it would be to lose it. If the break is long enough, you will also see what an ugly proportion of elements you have already lost!

Warning! By abusing Recency and Easiness criteria you can indefinitely reschedule some harder long-interval elements! You might be very disappointed in a year or two to discover that some elements have gained very long-intervals without a single repetition and have practically entirely faded from your memory!

The percentage values of the impact of individual criteria on sorting can be seen to the right from the slide-bars. Change those values by moving the sliders. For example, if you want to repeat rescheduled material with the easiest material coming first, put all sliders to the left and the Easiness slider on the right (Easiness=100%).

Note that investment criterion cannot drop below 2%. Other criteria can have no impact on sorting. This is only to prevent the situation in which all criteria have the value 0%.

To quickly reschedule outstanding repetitions using a given set of criteria do the following

1. Choose Tools : Mercy (e.g. by pressing Ctrl+Y)
2. Choose Criteria and set the sliders according to your preferences
3. Choose the maximum acceptable number of repetitions per day and type it in at Number of items per day. Alternatively, choose the period in which all outstanding repetitions should be done and type it in at Rescheduling period
4. Choose Update, e.g. by pressing Enter. This will display the rescheduling parameters: number of items per day, length of the rescheduling period, the date on which last outstanding repetitions will be made, etc.
5. If you are satisfied with your selection, click OK. Otherwise type in new parameters and choose Update again