Reader Joe DiNoto sent me to the following National Post (Canada) chart via Twitter, complaining about the circles. (The full chart is found here.)
This chart is supposed to show that the students in Quebec are wrong to go on strike against a roughly 10% increase in tuition fees because the cost of education in Quebec is dwarfed by those in other provinces. This particular message is visible by virtue of the small amount of space occupied by the Quebec "flower" relative to other provinces.
However, to convey that message would require only a chart of the average tuition of the seven provinces. The dataset here contains a lot more information than just the average: it has the tuition by major. But, does the general pattern of relative tuitions apply to individual majors? This chart type (a disguised bubble chart) does the reader few favors. (At least, the designer managed to keep each "petal" at the same angles; otherwise it would make our lives even harder.)
In order to bring out the tuition by major comparison, the following set of dot plots helps:
The purple dots are Quebec tuitions. The gray dots are the remaining provinces. We find that Quebec is at the bottom of the cost scale for every major. We also learn that the variance of tuition for dentistry, medicine, and law is very high. Surprisingly, the business degree is rather cheap - maybe the demand for it up north is lower?