Hmmm, not sure, maybe due to users having settings that only allow addition of their observations to projects that they have joined? If they joined the individual state park project, but not the umbrella project, then something could be wonky (though if observation totals match that seems less likely).
I’ve noticed counts are often different when viewing things like a taxon page versus maybe your own observation page.I think iNat algorithms count differently for different views of the data. In some cases this has to do with “species” sometimes being considered every different thing you’ve seen (1 Rosaceae + 1 Prunus serotina = 2) and other times only counting if you have gotten a specific ID ( 1 Rosaceae = 0, while 1 Prunus serotina =1).
Thank you for raising this question! I have noticed exactly this problem – a (growing) gap for species tallies (umbrella vs. collection) – in a project I am running. The discrepancy is more or less constant per collection project. It does not appear to be linked to parameters of either the umbrella project or the collection projects. Following this thread closely, thanks!
Sorry, I’ll keep looking into the observer count issue.
As noted on the page I linked to, calculating taxa using the “leaves” method is difficult to compute. We’re not using it on umbrella project pages because doing so could really put a burden on iNat’s infrastructure.
I actually compared stats, and even when I chose in filters different higher-than species levels, number of observations never got to be the same as what umbrella says, I did it on the project with the most observations in that umbrella, so you can check it.
I don’t understand why you’d need to calculate anything separately for umbrella projects SORTS. The number of species or observers per collection project is already calculated - why not just use those values?
I get the rationale for over all species counts and of course the total number of observers won’t be a simple sum of observers shown for each collection project.