Aggressive interval reset

[brownbat]

From a separate discussion:

Hi sorry for the hijack.
I love the concept, and it would be great to not have to adjust manually.

I just loaded AEF into anki and started doing reviews, but realized quite quickly that it was setting the interval on many cards back to 1d. Even some cards with 6 month intervals were being reset to 1d. Had to reset from an earlier backup. Any idea what might have went wrong?

Originally posted by @TRPV4 in #43 (comment)

EDIT: Just making it more clear this is a quote up front.

[brownbat]

TRPV4 - Sorry to hear you faced that. A few things could explain the experience, would love to dig in further.

One thing to note, the algorithm doesn't actually change or reset intervals directly, it only changes the "ease factor," which Anki then multiplies by the last interval to get the new interval. So to go from 6 months to 1 day by ease factor alone, your ease factor would need to be around one half of one percent.

In the settings you can set a minimum ease factor, which by default I believe is 100%, which means it wouldn't shrink your review intervals below their last value (after you recover from relearning). As an additional safeguard, after you're out of relearning, Anki automatically adjusts that ease interval back to 130%, which offers further protection.

It would be unlikely, but other add-ons might be interacting with AEF in unexpected ways. Do you have any other add ons which affect scheduling or buttons, like load balancer or advanced review bottom bar, just so I can look into those and rule them out?

Another possibility, one I'm really curious about, there are a couple settings which will directly affect your interval after you miss a card. Your card bounces back after these review steps, but during those relearning stages reviews get really close together for a bit. Sorry if you know this all already, but just trying to be as comprehensive as possible.

• Relearning Steps (aka Lapse Steps)
• New Interval

If your relearning steps are set to a few days, you might see short intervals during relearning, even though they will resume at a longer interval after you're out of those relearning steps.

If your New Interval is set to a very small percentage, it will reset your learning back to the beginning, as if you've never seen the card.

I'm a bit puzzled though because these should both have similar effects with or without AEF (AEF doesn't alter either or touch that part of Anki's code).

If you got to 6 month intervals with very few reviews, and had a higher than normal target for success, and you have a very low new interval in the lapse settings combined with a very short review period, I think these could all conspire to almost resetting the card to the beginning if you suddenly missed it for the first time. But I'd need a little more information to be sure this is what happened.

Would love to help diagnose further though either way. The best sorts of info to help me narrow in on what happened would be:

1. A snapshot of your Options > Lapses menu

2. A snapshot of card info

3. A snapshot of Add Ons menu, like so:

4. A snapshot of your AEF config:

I know that since you reset cards and removed the add on, you probably won't be able to provide some of these, but anything you can offer would be helpful.

[TRPV4]

Thanks for the lengthy response. This morning I tried to load in the "broken" backup from yesterday to take some screenshots, but couldn't find the exact cards that were reset to 1d. I will try to find these cards/break the add-on again in a few weeks.

I have a feeling that the card info is the most important piece of information... really sorry that I can't provide them at this moment.

What seemed to have happened was that my review cards were treated as having lapsed. Upon disabling the addon and going through the reviews, there were only three buttons "again <25min, good 1d, easy 2.3m" instead of the usual four. This was for all the cards that I went through.

What's weird is that when loading yesterdays "broken" backup into anki, everything seems to be fine. Intervals are back to normal, four buttons etc. Sorry if this isn't really helpful, I will try to replicate the issue in a few weeks.