Yeah, that's a fair point. These charts are misleading. Then again, if you generally trust charts for an easy interpretation of data, you're probably going to be misled anyway. Perhaps I express an unpopular opinion, but the only way to really get a handle on the data is to read the data. (I find it to be a rare occurrence that a chart exposes --- rather than oversimplifies --- relationships in the data. They're mostly okay for a cursory glance, but not for more. In this example, they're not even okay for a cursory glance.)
How would I determine if the pattern was linear or logarithmic, whether an observation was an outlier, or whether two series were related?
A tiny bit ad hominem, but I take it you are not a statistician. The first thing we do is to graphically illustrate the data, because human brains are so good at recognising patterns.
It is important to experiment with several variations of display, also including and excluding outliers and different series, to see if there are biases that mislead you.
Only then do we come up with a mathematical model to fit.
Actually reading the data line by line can be extremely misleading - because you can only compare a few numbers at a time, which fails to give you an insight into the overall variation.
I am in fact a statistician. I work in statistics, mathematics, and computer science. I am often severely frustrated by the oversimplifying and misleading natures of conventional charts.
I have seen good charts. Yes, they exist, and I actually see them quite often. It just so happens that the vast majority of charts and graphical illustrations I see are omitting details at best and dangerously misleading at worst.
Reading Tufte carefully, one realizes that (a) he's read more Derrida than he's willing to admit (there are entire unattributed quotations, probably by accident) and (b) great charting is an art form, perilously predicated on someone being both quantitatively educated and visually gifted.
There is no silver bullet but the table, and even then, Simpson's paradox is always ready to bite you.
Interesting. Me too, but I have been more into actuarial work for the last five years. One thing I have noticed is that they love tables of numbers. Maybe I need to reconsider.
How do you feel about waterfall charts? (presumably with the table attached)
Reading numerical data has its own drawbacks. E.g. your mind may perceive too much significance between 389 and 412. Even worse if any kind of error bars are involved.
> only way to really get a handle on the data is to read the data.
But charts are way easier to grasp than numbers. If you want to see the difference between the pace of adoption between two systems, it's much more telling to see it graphically than through numbers.
