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The use of lines in dot plots conventionally marks a break in the data, such as when there's a gap in the measurements or when 2 different series which are not totally comparable are plotted together. I thought that was the case here.


The question needs to be asked whether it would be better to superpose the graphs.


Yes I was going to say something along the lines of what Domingo has already said (though I wasn't aware of any convention about lines in dot plots). These lines seem to indicate survey breaks rather than big changes as such.


Domingo/Sumit: I haven't thought about the use of lines to indicate survey breaks. My interpretation of large shifts doesn't work for one or two of those charts.

I don't like the idea though - it requires that "knowledge in the head", knowing the convention; and it draws attention to the holes in the data set, rather than the data in the data set.

Ken: hard to tell unless we actually plot the superposed version.

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