My first impression was also that axis lines are a matter of aesthetics. But then I browsed The Economist’s visual styleguide and realized they also do something similar, i.e. omit the y-axis line (in fact, they omit the y-axis line on basically all their line / scatter plots, but almost always maintain the gridlines).
Here’s also an article they ran about their errors in data visualization, albeit probably fairly introductory for the median LW reader.
My first impression was also that axis lines are a matter of aesthetics. But then I browsed The Economist’s visual styleguide and realized they also do something similar, i.e. omit the y-axis line (in fact, they omit the y-axis line on basically all their line / scatter plots, but almost always maintain the gridlines).
Here’s also an article they ran about their errors in data visualization, albeit probably fairly introductory for the median LW reader.