Moving Averages, So Moved

The next time some jackleg says, “Well, it’s just one degree”, please take this post and stick it to him in an email. While no doubt a degree of politicization is in the equation, more often than not I hear the sputtering of a member of the innumerati. And, yes, I just made that word up (I think): See neologism.

Perhaps folks just didn’t spend enough time with batting averages while growing up. First week of the season and a little-known-player goes 6 for 10 and he’s batting .600. Phenom? Next week he goes for 0 for 10 and now his average is .300. Dramatic drop, right? Check back with him after 500 at bats.

He’s batting .200 and is headed down to the minors. On a glorious Saturday afternoon in Wrigley, he goes 4 for 4. Keep him in the Bigs? Uh, no. His average moved—staggered—up to .206. He’s gone.

Here’s another way to think about the way numbers and averages work. Before the weekend he got a hit in 1 out of 5 at bats, and after his last swings, he now gets a hit in 4.85 bats—wanna round up?

Which is why, if I were to bat against a big-leaguer and magically managed to squib some lame duck over second base for a single, I would never bat again, and so forever claim that I batted a thousand (1.000) against professional pitching. And for the sake of the scenario, just imagine I loped out that single. Somehow. Against all odds.

Okay, so a one degree temperature move—same deal with the way the hits and at bats numbers averaged out. One day the high is 80, and the next 50. Average high, then, is 65. Twenty-eight days later, the average high is 62. On the last day of the month, 105 degrees of sweltering awfulness. Month averaged 63 (and, yes, I rounded down).

Now, 364 days into the year, the average high has been 60. On the last day of the year—we’re living down under—115 degrees. Your new average high is—ta dum!—60.15. Better fix the fan.

Finally, 100 years of an average high of 60 degrees, with some leap years in the pile, and on the first day of the new year, 124 degrees—yikes! So, 60.001 is your new average daily high for the 100 years.

With our thinking caps on, what do we surmise? When an average, weighted with over 36,000 data points, moves a degree, up or down, in a short span of time—something might be in the air.

No, I didn’t check my work.

No, I didn’t show my work.

Homework: How many days at 124 degrees would be needed to move the 100-year-average to 61 degrees? Too cataclysmic? How many days at 100?