Line charts overlayed are fine, but they struggle when you have many series or many time intervals. Not that they are much better, but they are better.
Usually, I'm looking for rate of change of one item at a time, not all of them at the same time. After that, I'll compare them.
Stacked bar charts, IMO, seem skewed in who gained the most over a period, but not the individual gains. I have no idea what green really ended up with by the end of it because it just kept getting pushed towards the top. I have to constantly go to the left and compare ranges with the previous stack.
Can you recommend an Excel addon/color chooser or website so that persons with normal vision can test their charts and color choices for the four known kinds of color deficients?
It would of cource help you, if the chart lines have different line patterns (dottet lines).
http://colorbrewer2.org has some good palettes for data presentation which they describe as "colorblind safe". I assume this means for all kinds of deficiency.
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I was going to leave this as a comment on his blog but apparently comments are closed now.
Stacked bar charts are better, but only a little better.
Line charts overlaid on top of each other are most clear, to me.
Like this: http://i.imgur.com/kyvpiax.png
Line charts overlayed are fine, but they struggle when you have many series or many time intervals. Not that they are much better, but they are better.
To me they are far and away the worst, probably because I'm color deficient.
I'm also color deficient, but disagree.
Usually, I'm looking for rate of change of one item at a time, not all of them at the same time. After that, I'll compare them.
Stacked bar charts, IMO, seem skewed in who gained the most over a period, but not the individual gains. I have no idea what green really ended up with by the end of it because it just kept getting pushed towards the top. I have to constantly go to the left and compare ranges with the previous stack.
Can you recommend an Excel addon/color chooser or website so that persons with normal vision can test their charts and color choices for the four known kinds of color deficients?
It would of cource help you, if the chart lines have different line patterns (dottet lines).
http://colorbrewer2.org has some good palettes for data presentation which they describe as "colorblind safe". I assume this means for all kinds of deficiency.
I forgot to link to this picture on Wikipedia: http://en.wikipedia.org/wiki/Color_blind#mediaviewer/File:Sa...
Is that not a problem with stacked charts?
No, because they are stacked. Overlapping is a problem because you have a bunch of colors that very nearly look the same crossing over each other.
With stacks it's much easier to track along based on contrast alone.