"The urge to contextualize the data is a good one, but context does not come from empty vertical space reaching down to zero, a number which does not even occur in a good many data sets. Instead, for context, show more data horizontally! "
A non-zero baseline is fine in some cases (line chart of the temperature of a person with a fever for example), but the issues here were multiple charts at varying Y scale starting points, and bar size comparisons of a property that we do want to go to zero (zero failures).
"The urge to contextualize the data is a good one, but context does not come from empty vertical space reaching down to zero, a number which does not even occur in a good many data sets. Instead, for context, show more data horizontally! "
-- Edward Tufte, October 18, 2001
http://www.edwardtufte.com/bboard/q-and-a-fetch-msg?msg_id=0...