Some thoughts about improving/splitting the urgency score

[Cito]

Obsidian Tasks currently provides an option to sort tasks using an Urgency value. This is a great feature, but there are two things where I feel it needs some improvement.

First, the current algorithm for calculation of the urgency (adopted from TaskWarrior) is a bit arbitrary and can sometime yield values which are not what I would expect (see #691 for instance). @claremacrae and I are currently trying to solve this by making the score function configurable (see also #1112).

Second, I think the naming "urgency" for this value not the best choice and can be misleading. My point here is that the word "urgency" already has a well-defined meaning in time management systems, as one of the axes of the Eisenhower matrix (see Wikipedia time management - Eisenhower method). It covers only the aspects of the task that deal with timing the task (described by the due, start and scheduled dates in Obsidian Tasks). The other axis is the importance (described by the priority in Obsidian Tasks).

However, our current urgency value conflates both axes, it contains portions of both urgency and priority. That's why I think a less specific name like "rank" or "combined score" would be better for what we currently call "urgency".

This comment by @claremacrae made me think that in fact it would make sense to provide three different score values, urgency, importance, combined, using separate formulas. The formula for the combined score could then reuse the urgency and importance scores. And you could create different view, sorted by urgency, importance and combined.

Sorting by importance would be by default the same as what is currently called "sort by priority", but a custom formula for importance could also factor other factors in, like automatically boosting the importance of tasks in a certain folder because that folder deals with an important goal of your life, or boost tasks with a certain keyword.

The combined score would be by default the sum or product of the urgency and importance scores, but this should be configurable as well.

This splitting of the scores into three different values (functions) also makes them easier to configure, allowing to customize only the parts of interest.

What do you think about these ideas?

[claremacrae]

Very interesting idea!

Quick initial thoughts - all about small details.

• I guess this would be a breaking change, as it would change the behaviour of sort by urgency
• I would like there to be a more meaningful name than sort by combined. Combined what? Perhaps even sort by eisenhower?
• The importance will use priority. If so, how will we avoid confusion over the different names for the same thing.
• Do you anticipate separate customisation formulae for importance and combined? I think so.

[Cito]

• Indeed, this would be a breaking change, since sort by urgency would then only sort by urgency, not by priority. But it would not be a big deal, the users could either change their filters if they meant to use the combined score, or leave them if they actually wanted to sort by urgency.
• We need to come up with a better name for the combined score, yes. MyLifeOrganized calls it "computed score", but this is also ambiguous. But maybe we should give the functions names like "computed urgency", "computed importance" and "computed rank", so we can distinguish between sorting with the chosen importance level (high/med/low) and the computed importance which may also involve other factors like keywords in the task.
• Yes, confusingly, many call the combined score "priority", and call what we call priority "importance" or "impact" (see for instance here and here). So to avoid confusion we may want to rename that as well even if it would be another breaking change.
• Yes, my idea is to use separate formulas for the different scores. But the combined score could reuse the results of the other two formulas. So it could just calculate the sum or product of them. This makes things more flexible and modular.

[claremacrae]

I've made an additional suggestion building on this: #1162

Introduce a new customisable score property, allowing any number of user-named algorithms.