Smoothness of discrete data I'm having a hard time putting my question into words, so I made a few pictures.
Look at this plot:

Clearly, everyone will agree that these data points are following some nice smooth and continuous function. In the following plot, this is not the case.

What I'm looking for, is a word that describes this difference:

Data set A is much more ??? than data set B.

Is it smooth? Well-behaved maybe? Thanks in advance!
 A: The term you're looking for is "variance." When you look at the data, you fit a curve to it. The curve is smooth, but it's the same curve for both data points.  The difference is how much the data varies form the curve, usually measured by $\frac{1}{n}\sum (f(x)-x)^2$ where $f(x)$ is the equation of the curve. The square root of this quantity is known as the "standard deviation"
You can read more here.
A: You can use "smoother". And the reason will be following:
You can find the Total Variation (TV) of both the data sets. The variation of B will be much more than A.
The formula of total variation is given by,
$TV(u)=\sum_i |u_{i+1}-u_i|$.
A: It looks like data set A is more smooth than data set B because you can easily see the trend that is there. But, the other thing to know that data set B is [most likely] more well-behaved than data set A because you can get from point to point in set B "freely" without "any traffic" by any points, as compared to set A. 
Short answer: Data set A is much more smooth than data set B.
