Common wisdom in the astronomy circles is that Vox Charta represents the biased view of the astronomy community which is focused towards extragalactic topics. Let’s see how much truth is in that statement.
Papers that contain keywords connected with galaxies and cosmology seem to indeed to be upvoted more often then papers connected with other fields. The dashed line is 1:1 correspondence and we would expect the points to be on this line. Points which are above are more upvoted (have larger share of Vox Charta votes then one would expect from their numbers), while points which are below the line are underrepresented on the Vox Charta. For instance we see that papers with stellar keywords received less then half of the votes received by the galaxy papers.
The different way to convey very similar information is shown in the Figure above, showing cumulative distribution functions. Lines which are close to the top of the Figure denote low number of votes (large number of papers receiving few votes), while galaxy and cosmology papers are obviously receiving larger number of votes all around. 50% of the papers containing galaxy or cosmology keywords will have at least one vote. We can see that almost all of the most upvoted papers (25+) will be concerning galaxy and cosmology topics.
Ok, so if you life goal is for your papers to have many Vox Charta votes, you bettwer work in the extragalactic topics. It also seems that is beneficial to have many authors on your papers, as seen on the Figure above which shows correlation between number of votes and number of authors on the paper. I have dashed the area where there are more then 10 paper per one point. Beyond that, there are only very few papers in each bin so any statistical statements are pretty weak.
It also seems it is good to write longer abstract, hopefully because authors have a lot of smart thing to say. As before, dashed shows area where there are more then 10 papers per point. There seems to be increase to around 250 words (abstract limit for many papers) after which there is stabilization trend and possible decline.
So, summarizing our conclusions from the first post and this one, to get a lot of votes, work in extragalactic topics, submit your paper so it on top of astro-ph list (competition is lowest on Tuesday), get a lot of co-authors and write long abstracts (possibly also do good science, but this is only based on anecdotal evidence).