scroll depth

[metmarkosaric]

No description provided.

[RobertJoonas]

Fantastic job on this PR, @metmarkosaric and @Hricha-Shandily! 🥳

A couple of suggestions with more technical context inline. Feel free to adjust the copies.

[RobertJoonas]

I think the metric definitions page should also give a pretty accurate description of how things work technically. Reading this paragraph, I get the impression that clicking this link will take me to the technical description.

Proposal: lets include something like this on the /docs/scroll-depth page:

How is scroll depth tracked in Plausible?

When a user first opens the page, a percentage of it is visible already. That height visible to the user, divided by the total height of the page is the initial scroll depth percentage. We then keep track of the maximum depth as the user scrolls, and reaching to the very bottom, the percentage would become 100%.

Described above is only a single pageview. What if a user visits the same page multiple times during their visit, scrolling to different depths each time? In that case, the scroll depth of that particular page for that visit is simply the maximum up to which they reached across all pageviews on that page.

Finally, the average metric that you can see in your dashboard is simply an average of all visits.

[Hricha-Shandily]

This is good info but I have noticed we don't generally include much about technical details regarding any feature in the documentation. I guess this is to keep the doc as simplified to comprehend as possible and not include info that has potential to confuse the reader (no matter how simple we make it). Is that so, @metmarkosaric ?

[metmarkosaric]

@Hricha-Shandily yeah, that's correct. in general, we tend to keep more (technical) details out of the docs by default. we do sometimes surface some details (see for instance this on how locations work: https://plausible.io/docs/countries#how-location-reporting-works) but this is more if we notice that something is unclear and/or people are asking. so i say we keep this info in mind and add it to the docs at a later stage if it turns out that simplified docs are not clear enough

[Hricha-Shandily]

Sounds good

[RobertJoonas]

There are two limitations that I think we should mention in this section.

1. Number of conversions might appear lower than it really is

Our tracking script captures scroll depth at the moment when the visitor leaves a page. But it can't always do so due to browser limitations. E.g. sometimes, browsers won’t detect when a user leaves if they switch apps or move the browser to another screen. While we use best practices to maximize accuracy, some of these events will always be missed.

2. Number of total conversions is not available for Scroll Depth goals

While for pageview and custom event goals we can easily tell how many events there were in total, we cannot say the same for Scroll Depth goals as scrolling is an action that gets measured continuously during a pageview.

[Hricha-Shandily]

Thanks Robert!
I have added the second point, @metmarkosaric . If it looks good (you should be able to see it below), I will commit the suggestion.

For the accuracy part (first point), I am thinking it is something we don't need to say as it could overcomplicate and unnecessarily raise questions about our accuracy and increase the support volume as well.

[RobertJoonas]

Commited the suggestion below. Thanks @Hricha-Shandily!

About the first point though, I do believe it's important to note this in the docs. We could perhaps phrase it a bit differently, but it's a significant factor affecting an important number on the dashboard, so I feel like it should definitely be added into the docs. And the "Scroll Depth Goals" section in the scroll_depth.md document sounds like the right place for it.

That said, it's also fine by me if we roll it out like that and see how people will respond first.