Statistics Is an Art

When you say the word "statistics" to people, most think about math. But not me. I think about art.

I was reminded about this when I received the following e-mail recently:

Hi Eston --

I read your paper on "Weather Forecasts: Just How Reliable Are They?" and have a few questions. I am a retired engineer who enjoys data and would like to do a similar study for my home town. I want to look at the NWS and our local TV stations' 7 day forecasts (high, lows and precip.).

I was wondering if you have more details on the statistical analysis. I did take statistics for engineers in college in the 1960s, but have forgotten almost all I learned. I also did some statistics at work, but we had statisticians to do the hard stuff.

I enjoyed your blog "How I Learned to Love Statistics." I noticed you said "I gravitate to words, not numbers. In school I was the kid completely unfazed by William Faulkner and James Joyce." All our tacticians were even more nerds than us engineers and never entertained reading literature. When you said "I've overcome fear of statistics and acquired a real passion for it. And if I can learn to understand and apply statistics, so can you," it reminded me of understanding how to calculate the numbers, but not really knowing how or when to apply a certain test. I do remember my teacher saying that she wanted us to understand what the numbers meant and to hire a statistician to set up tests and provide guidance. I believed her.

Barry

A lot of people have asked about this article, I think because it's fun to take real-life data about things like the weather and use it to better understand how things work. Barry's e-mail gave me an opportunity to go back and re-read this article, which I co-wrote with my colleague Michelle Paret last year.

Most of the analyses we did in the weather article are very straightforward in Minitab: you just go to the menu item, enter the appropriate columns of data into a dialog box, and press "OK."

For instance, to create the time series plot of actual vs. forecasted temperatures shown in the article, we just selected Graph > Time Series Plot in Minitab. That brings up this dialog box, which lets us choose what type of Time Series Analysis we want to show:

Since we were looking at how four different measurements compared, we wanted the "Multiple" option. That brings up a dialog box in which we just select the four columns that contain our measurements and set the appropriate time scale.

Time Series Analysis with Multiple Variables

When you hit "OK," Minitab performs the analysis and returns the graph shown in the article:

Behind the scenes, Minitab does all the mathematical heavy lifting, so there are no formulas to enter or anything of that sort. Minitab let us focus on the results of the analysis, rather than the calculations.

Barry's note made me think about my personal relationship with statistics and data analysis, and how statistical software has facilitated that relationship. My studies have emphasized applied statistics, and while I've learned the theoretical and mathematical underpinnings of the analysis, that's not where my interests lie.That's why statistical software is such a boon. Again, it does the mathematical heavy lifting so we can focus on what the analysis actually means.

Just as a composer might hear birdsongs and use a palette of timbres, tones and tempos to create a work that casts a new reflection on what she heard, a statistician needs to be able to look at the data available and use the palette of tests, transformations and graphs to extract illumination from those numbers. Moreover, a statistician needs to be able to understand not just what can be done with the data already in hand, but also what data could be collected.

Statistics confounded me for years because I kept getting hung up on the math. What finally got me over that hurdle was realizing that while statistics is certainly a branch of mathematics, it's also an art. The calculations need to be done, but you can use different tools to do them. And like anything else, some tools are better than others. You could do an analysis with just paper and pencil, but that would be like driving cross-country in a soapbox racer. In contrast, using software like Minitab to perform the analysis is more like flying cross-country in first-class: fast and relatively painless.

In other words, once I realized better tools were available to me, the art involved in statistics became much more apparent, and I became much more interested.

There's nothing that can't be analyzed with statistics; the art is in finding the metrics that let you do it in a meaningful way.

Barry's comment about learning the calculation without understanding when and why you'd use it really resonates with me. The fact is, unless you're analyzing data every day, you will forget what those formulas are and which tests do what. That's one major reason we added the Assistant to Minitab, to provide an interactive tool that guides people to and through the right type of statistical analysis, and then helps them interpret what the analysis means.

If you'd like to explore the art of statistics, and you don't already have it, you can try Minitab free. It's the complete, full package, and will work for 30 days. If you do try it, please let us know what you think. We love to get feedback from the people who use our software.