add a retention chart

[chadwhitacre]

[chadwhitacre]

Here's the spreadsheet we've been working with:

https://docs.google.com/spreadsheets/d/1SiEz6TtRFqmywEEIQkrIzqqBo9tEf3kZ0oS-jlGT7-s/edit?usp=sharing

[webmaven]

Looks good for the triangle style, but something is strange in the data, I noticed a few places where the data wasn't evenly stepped, and I also see that not all boxes are square, changing the angle. May want to play with the color distribution a bit.

[rohitpaulk]

I don't have any objection to having this charts on /charts, but I think it's unnecessary. This is more of something that should be on IG, isn't it?

[chadwhitacre]

[chadwhitacre]

IRC

[chadwhitacre]

[webmaven]

Looks good enough to ship. I do have some questions about the data, though, there seem to be a couple of spots where a nibble has been taken out of the edge, or a strip peeled off the first three months or so. Any ideas about what's causing that?

[webmaven]

I think you might also play with the color a bit. Rather than having 'Gratipay green' representing 100%, you might try putting it at 50%, with 0% still being white, and 100% being black.

[chadwhitacre]

Rebased on master.

[chadwhitacre]

Here's what the new Active Ratio chart looks like in context:

[webmaven]

Yup, that drop in activity is what worries me.

Incidentally, although the retention chart is already good enough to ship, I've though of some interactive features that would be useful to add.

So, next steps?:

• First, color code the cohorts based on the latest activity % data for each.
• Besides popping up tooltips when mousing over the triangle, you can also color code the cohorts based on the activity in that row of the triangle (greying the ones that have no data).
• At some point, you are also going to want to include attrition data in these same charts, whether that is 'inactive', or what might be better, 'deleted accounts'.
• At some point after that, splitting activity into 'giving' and 'receiving'.

What we want to identify are cohorts that are both larger and more active over time. When identified, figure out why they are so, and go get more / design features that please them in particular. Secondarily, particularly active cohorts whatever their size.

[chadwhitacre]

Per convo at gratipay/inside.gratipay.com#89 (comment), here is engaged users and ratio:

[chadwhitacre]

[chadwhitacre]

Considering replacing "Active Users" with "Givers." IRC

[chadwhitacre]

Rebased on master.

[webmaven]

Minor tweak: Would "Percentage of active givers out of all users" be more meaningful than "N per 10,000"? The chart should look more or less the same.

[seanlinsley]

The benefit of using "out of 10,000" is you can have a round number instead of a fractional percent.

[chadwhitacre]

I'm closing this PR. I'm glad we've gotten our feet wet with retention analysis, but adopting retention analysis as a key decision-making tool will make a lot more sense after we've mostly built the product we're trying to build. Right now we have a clear picture of what we're trying to build (well, an increasingly-clear picture; see #3220), and plenty of obvious work to do to get to "version 1." Let's revisit retention after version 1.