Seeking clarification on the identification algorithm with disagreement

[sego7]

I’m new to iNat, and when identifying, I keep coming across a particular type of situation with disagreeing IDs. I’ve tried reading about this in the forums, but get conflicting results (not just on best practice, but on how the underlying mechanism works).
(Edited to clarify by higher I meant broader)

Situation:

• Person A will suggest a species in tribe A
• Person B will disagree with them and suggest a species in tribe B

So currently both the observation’s community taxon and observation taxon are currently at the broadest level those two IDs agree on: Family 1

Now, I can’t identify this plant to species, but I can identify it to genus or tribe, and I agree with person B.

But should I add an identification that is broader than the ‘Species B’ identification (e.g. ‘Tribe B’)? I’ve seen some people say a broader ID shouldn’t be added (because it downgrades the observation or requires more IDs at species level to reach research grade), some people say I should add it, and some people say I can add it but it doesn’t do anything useful.

As I understand it:

If I add an ID of Tribe B, it won’t change anything yet—2/3rds are needed to change the community taxon, so another ID would be needed to move this observation finer than Family 1. And the observation taxon stays at Family 1 as well.

Instead, this is what adding my ID of Tribe B would do:

• Without my ID, if another ID is added at species level, the observation’s community and observation taxon will stay at Family 1.

• With my ID, the community taxon observation will change to Tribe B and the observation taxon will change to species B (since the community is in agreement on Tribe B and the observation taxon doesn’t need agreement on the finest level to switch to it). And by changing the observation taxon (which search results work on), hopefully it will be more likely to show up in the search results of people who can add those last two required species IDs.

Can anyone confirm or correct my understanding? Any thoughts on if I should I add that broader taxon identification? And does that answer change depending on the taxon level I can ID it to, the type of taxon (e.g. different types of plants or across kingdoms), how long it’s been since the last ID was added, or how active the previous two identifiers are?

Also, I keep seeing discussion of how ‘disagreeing IDs’ complicate this. However, I can’t find the relevant buttons mentioned (in either the web version or android app). From what I’ve experienced, disagreement or not seems to be an automatic function. After submission, if it’s in a different taxon than the current community ID, then text is automatically added below my ID saying what it’s disagreeing with, but if it’s in the same taxon or a higher-level taxon of the same taxon, then no disagreement text is displayed. Am I just missing something here?

And can anyone clarify if the disagreement text or agreement absence of text is added based on the community taxon or the observation taxon?

Thanks

[thomaseverest]

@sego7

With my ID, the community taxon observation will change to Tribe B and the observation taxon will change to species B

If I’m understanding your example correctly, this isn’t what happens. Tribe A + Tribe B + Tribe B + Species in Tribe B = observation and community taxon of Tribe B.

@sego7

should I add that higher-level taxon identification?

I’m not exactly sure what you mean by “higher-level”, but generally I think this is helpful. Some people may be annoyed by supporting IDs, but you haven’t described that here. You can read more about those here:
https://www.inaturalist.org/pages/help#identification

@sego7

Am I just missing something here?

Are you thinking of something like this?

This happens when you add an ID that is broader than the observation taxon. You could either be disagreeing or not, so you have to clarify. Some people think adding broader IDs that aren’t disagreements is annoying (basically the same sort of supporting ID as above).

@sego7

And can anyone clarify if the disagreement text or agreement absence of text is added based on the community taxon or the observation taxon?

I believe it’s based on the observation taxon just by looking at some example observations.

[DianaStuder]

If you click What’s This at the CID
scroll down past the wall of words
and iNat explains the CID for this obs with these IDs.

Add the ID you want - then click to see if it does what you expect it to for the CID. (You can delete that ‘wrong’ ID and try another one)
Your DISagreement (sorry typo) can be hard (definitely NOT) or soft (not sure) - which have 2 different effects on the CID.
(And to make life more interesting / confusing there is the CID on the right, and a display ID up top - which do not always agree with each other!)

[twainwright]

@sego7

Now, I can’t identify this plant to species, but I can identify it to genus or tribe, and I agree with person B.

But should I add a higher-level identification? I’ve seen some people say a higher-level ID shouldn’t be added (because it downgrades the observation or requires more IDs at species level to reach research grade), some people say I should add it, and some people say I can add it but it doesn’t do anything useful.

I’m not quite sure what you mean by “higher-level ID” - higher than what (the community ID, the lowest ID posted so far, …), You should always add an ID at the lowest level you are confident. If you are not confident below the current community ID, then it is not necessary to add an agreement, and doing so, as you mention, may slow the process of achieving a lower-level community ID. However, there may be other reasons to add an agreement at that level. I sometimes do that for a couple different reasons: first, if I think the evidence is not there to get a lower-level ID (in which case I might also check the “as good as it can be” box), or second, if it is a group that I am working on and I want to record my opinion (that I couldn’t ID it further) so I remember that when I next look at the observation. In either case, I only do this with taxa that I am quite familiar with.

@sego7

As I understand it:

I think your understanding is correct.

[amr_mn]

Adding an ID (without disagreement) at a broader (higher-level) taxon (even “Life”), doesn’t change the observation ID or the community ID and doesn’t impede reaching any finer (lower-level) taxon consensus.

(Apologies, I can never remember if “higher-level” means “broader” or “finer”, so I kept those descriptors after I looked it up.)

From the “What’s This?” explanation on the Community Taxon:

The algorithm: for all identified taxa and the taxa that contain them (e.g. genus Homo contains Homo sapiens), score each as the ratio between the number of ‘agreements’ - cumulative IDs for that taxon over the sum of the cumulative IDs, ‘disagreements’ - the number of IDs that are completely different (i.e. IDs of taxa that do not contain the taxon being scored), and ‘ancestor disagreements’ - the number of more conservative IDs that disagree with the finer taxon. For the identified taxa that have a score over 2/3 and at least 2 identifications, choose the lowest ranked taxon.

[sego7]

Thanks everyone for the clarification.

@thomaseverest

If I’m understanding your example correctly, this isn’t what happens. Tribe A + Tribe B + Tribe B + Species in Tribe B = observation and community taxon of Tribe B.

You’re right. I found an observation that fit the described situation (tribe A + tribe B + species B in tribe B + species B in tribe B) that I could be the fourth person on. Because of the disagreement, it takes 3 of the same species identifications to move the observation taxon to species level (same as the community taxon).

@thomaseverest

I’m not exactly sure what you mean by “higher-level”, but generally I think this is helpful. Some people may be annoyed by supporting IDs, but you haven’t described that here. You can read more about those here:

https://www.inaturalist.org/pages/help#identification

I should have been clearer—I edited my post to clarify that. By higher-level ID, I meant an id that was broader than what a previous identifier has submitted (but not disagreeing with them). So a ‘tribe B’ ID when the previous identifier submitted a species ID within tribe B.

I looked at the link again and realized that if iNat adds the ‘Leading’ icon to the ID, then that’s what the ID is doing in the algorithm.

@thomaseverest

Are you thinking of something like this?

This happens when you add an ID that is broader than the observation taxon.

Yes, thank you, that’s exactly what I’ve seen described. I suppose I just have never yet truly submitted a taxon broader than the observation taxon that’s not already explicitly disagreeing.

@twainwright

If you are not confident below the current community ID, then it is not necessary to add an agreement, and doing so, as you mention, may slow the process of achieving a lower-level community ID.

Do you know the mechanism behind why that happens, even with a non-disagreeing ID? I think worry about that type of situation is what’s caused a lot of my confusion. I can’t figure out how that would be true, so I can’t figure out how to avoid it.