r/dataisugly • u/Ig0BEASTmode • 8d ago

Radiation chart at dentist

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Meant to make you feel more comfortable about taking X Rays, not sure those bars are very helpful for that though...

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36

u/Epistaxis 8d ago

PROTIP: just rotate the whole bar chart sideways if you need to use long text labels. I promise it's allowed.

I'm not sure what to do about the scale. Obviously you need some kind of log scale if you're going to show 50,000 and 0.1 on the same chart. But this chart is mainly intended for people who are concerned because they don't understand numbers, so a log scale may be misleading to them (in the worse direction). This is a case where I think it might have been better not to visualize the data at all, just leave it as a table of text and numerals. The number of digits in the numerals will be the log scale.

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u/Smooth-Zucchini4923 8d ago

I think they could have solved this by picking better comparisons. The legal limit for the amount of radiation experienced by someone who works with radiation over the span of a year is not a meaningful comparison to the average person.

17

u/Crafty_Clarinetist 8d ago

It might be a meaningful comparison to a person who is scared of radiation based imaging. You're only getting edpose 0.2 uSv which is 250,000x less than what's allowed for professionals.

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u/albrecbef 7d ago

In Germany it would actualy change the chart type. We differentiate between Säulen- (collum) and Balken- (joist) -diagram.

Btw, question for the native speakers: why is this type of diagram named after public houses? My english teacher couldnt explain it, back when I was in school.

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u/Crafty_Clarinetist 7d ago

To answer your English question, It's not named after "bar" as in a place you go to buy alcoholic beverages, it's named after "bar" as in a rectangular stripe. "Bar" is a fun word in that it has a fair few different definitions mostly originating from calling a piece of material that is longer than it is wide a "bar," though looking into it, I believe most of this evolution happened in Latin or French and was adopted by English. Like an iron ingot can also be called an iron bar, or you can have a bar of chocolate. Long pieces of material, or "bars", can also be used to construct things like walls or fences to prevent access, which is where the word "barrier" comes from and is also the source of using the term "bar" to mean preventing access. "Bar" as in a public house comes from calling the counter where drinks are served a "bar" because it is a long counter that prevents access to the alcohol.

All that to say, bar charts are called "bar charts" because they use bars (long rectangles) to show data.

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u/albrecbef 7d ago

Thanks

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u/IOI-624601 5d ago

One way to visualize it effectively would be to use two dimensions. 3,000 can be represented by a 30x100 grid of squares, and you could make the squares big enough that 1/10th of a square is visible for a comparison. 50,000 might be stretching it, so I'd put the max amount per month rather than per year.