Brushing up on means and medians can help journalists

Everything I see points to the coming July 4 weekend signaling the absolute worst of our current travel nightmare, combining staffing shortages, slow regrowth after the pandemic, high energy prices, and raging inflation.

Of course, a large percentage of all travelers will be fine, and they will handle more expensive tickets and gas in the same way that people who REALLY want to see, say, the Colorado Avalanche hockey team play in person. Playoff tix were going for upward of $2,000 just a couple weeks ago. 

Life is full of choices, and for most Americans there is enough flexibility to spend more or less, depending on values and enthusiasm and desire. Holiday travel seems like a choice, though the urge to get out of town and check in with relatives... or simply hang out somewhere new or exciting or both is strong. 

A chance of delays and even cancellations is just enough to stop those eager to visit somewhere.

A recent study says the average American family spends 2.57 percent of its available income on gasoline each month, and recent price hikes have raised that percentage quite a bit compared to previous expectations. I have previously mentioned in this blog that every increase in gas per gallon of one dollar leads to about an additional $55 in monthly gas bills for average drivers.

But we know that "average" is sometimes not very helpful... and I would guess that the range of amounts spent on gas each month is quite large. I was surprised to find that Alabama drivers pile up way more miles each month than many other states. Many who live in dense metropolitan areas like New York City or Washington, D.C. simply don't pile up the miles, no matter how high or low gas prices get. 

I was thinking that we need to teach young journalists to more closely examine the terms "average" and "typical," and create discussions over which of the two measures is more useful.

Everything I found searching online depended on "average," or simply adding up all the miles driven and dividing the total number of driving family members into that number, and then multiplying the cost of gas. In theory, you could have a lot of drivers like Kathleen and me who fill up the tank once per month... maybe. You could have a select few drivers, like contractors for Uber, who might pile up ten thousand miles in a month. Computing the average of those diverse results gives a number that is WAY too high for some percentage of the population that doesn't drive all the time and WAY too low for ride share drivers.

And I'm not sure exactly what we learn from that average.

A "typical" driver might accumulate (I am making this up) 30 miles a day... or make it 100 miles a day... the point will be the same. If we can identify the "typical," we may get a more useful figure. This is the median in "stat talk," and the median is simply the number that sits exactly in the middle of the range, with an equal number of instances of smaller and larger data points.

I only spent a few minutes searching online for the "mean number of miles driven by Americans," but rarely got any links that were not AVERAGES. Maybe a calculation that includes many millions of data points, all needing to be ranked in order to find the data point in the exact middle, is just too complex. Or maybe the sites didn't see the point.

I finally found one site that claimed, after applying standard deviations, that the mean number of miles driven by Americans is 12,494, or about 1,041 per month. The average is 14,263 per year or about 1,188 miles per month. Those two figures are not dramatically different, but adding 140 miles per month at $5 per gallon comes to $735 dollars of difference... and that is substantial.

I maintain that "typical" has to be the best number to refer to when we are reporting on almost anything that involves large numbers of people or businesses, as well as simply measuring dollars and cents and miles. 

Schools are full of extremes, and some individuals are far off the charts in terms of extreme choices, intellectual ability, home life, mental health, etc. Schools and governments tend to aggregate everything and arrive at averages to compare and contrast. If a school's average score on some standardized test goes down or up, we may be overdoing our sorrow or joy, respectively.

We just need to keep educating students that "average" is unlikely to look like them. Those average resemble them. 

Typical behavior is much more likely to help us in choosing topics and appealing to readers, particularly if we are most interested in reaching the widest audience.