Ain't no mischief like statistical mischief.

Consider a recent Vanderbilt University survey. It found that 52 percent of Tennesseans thought their own public schools deserved a grade of A or B. But they took a notably less cheery view of the state's schools overall.

Translation: My school is great. Yours? Well, get ready for the late shift at Taco Barn.

The most dishonest thing to do with such a finding is to cite it as proof that all is more or less dandy in the schools. It is easy but misleading to suggest that if people like their own schools -- which they know the most about -- their worries about the quality of schools they're less familiar with are irrelevant.

Here's the problem with that theory: Parents might not like to admit to pollsters, "Yeah, my kid's school is pretty much a dropout mill," because that would force them to ask themselves whether they're trying to secure a better education for their children. Far easier to tut-tut about those "other schools."

Enhancing this effect is the natural impulse to defend the institutions in one's own back yard. Methinks the Beach Boys once urged, "Be true to your school." Nothing wrong with that -- unless by "being true" you mean substituting wishful thinking for actual data on academic achievement.

An article by The Tennessean illustrated the point perfectly. In it, an alumna of Hillwood High School in Davidson County raved about her alma mater. Alas, Hillwood's performance is no cause to break out that case of Sunny D you were saving for Administrative Professionals Day.

According to the Tennessee Department of Education, 63 percent of Hillwood's students score at the basic or below-basic level in math, compared with only 37 percent who score at the proficient or advanced level. The far better, if not sonnet-inspiring, statewide percentages are 51 and 49, respectively. While only 30 percent of black students across Tennessee are in the below-basic category in math, the figure rises to 52 percent of black students at Hillwood. And nearly 23 percent of Hillwood's students have been suspended or expelled at some point, compared with 8 percent statewide.

I'm glad if the young woman quoted by the Nashville paper learned a lot at her school. She beat the odds. But many of her fellow graduates and non-graduates plainly didn't. So the question isn't who feels good about a particular school but whether the school is getting good results.

And since we've stepped outside our comfort zone anyway, it would be helpful to know whether the schools most vigorously admired by their communities are the very ones that have the lowest achievement. As noted crooner Eminem demonstrates, high regard for oneself -- or for institutions with which one is affiliated -- needn't be delayed simply because the facts suggest that jet-fueled humility would be more fitting.

Think of the star athlete whose self-esteem jumps into hyper-drive when he ekes out a C that keeps him on the team. Now think of the A student who has a breakdown when her impressive grasp of the Marshall Plan and photosynthesis does exactly nothing to save her from a B in typing class -- or keyboarding or advanced texting or whatever they call it these days. No self-esteem there, though it would be more justified. (And for the record, I could have lived a contented life without ever again thinking of the word "photosynthesis.")

The point is, inordinately bad schools can enjoy inordinately elevated respect.

That should put to rest the notion that a school's warm relations with its community prove the school excels at anything besides community relations.