Guides  /  ,

Summary Statistics Tell You Little About the Big Picture

By Nathan Yau

Mean, median, and mode. These are the first things you learn about in your introductory statistics course. It’s often all you hear about when you see data in the news. People form policies for populations, based on the generalized numbers.

However, these summary statistics can only tell you so much about a dataset, which means you can only learn a limited amount about what the data represents — the people, places, and things.

If you’re the one who consumes the data, you should wonder what the means and medians actually represent. If you’re the one who analyzes the data, spend time with the most granular that time and resources allow for. Something more interesting will almost always come out of it.

Chart Type Used

Histogram

It looks like a bar chart, but it reads differently. The baseline is continuous instead of discrete categories, which allows one to see distributions.

Favorites

The Changing American Diet

See what we ate on an average day, for the past several decades.

Think Like a Statistician – Without the Math

I call myself a statistician, because, well, I’m a statistics graduate student. However, the most important things I’ve learned are less formal, but have proven extremely useful when working/playing with data.

How You Will Die

So far we’ve seen when you will die and how other people tend to die. Now let’s put the two together to see how and when you will die, given your sex, race, and age.

Visualizing the Uncertainty in Data

Data is an abstraction, and it’s impossible to encapsulate everything it represents in real life. So there is uncertainty. Here are ways to visualize the uncertainty.