Student readiness "near average?!" What does that mean?

PREPAREDNESS FOR HIGH SCHOOL, ACT TESTED

Senate Bill 130, requires all Kentucky high school juniors to take the ACT exam starting in 2008. One of the tests required by the bill, called EXPLORE, measures whether eighth-graders are prepared for high school. The other, called PLAN, shows whether 10th-graders are ready for the ACT, a college entrance exam.

Yesterday, the Kentucky Department of Education released data from these new readiness tests that were given to middle and high school students for the first time in October and eventually will factor into overall state achievement scores under the Commonwealth Accountability Testing System.

How'd we do?

Statewide - below average, again.

Kentucky eighth-graders were nearly as prepared for high school as their peers nationwide, while the state's 10th-graders were not as ready for the ACT college entrance exams as similar students nationwide.

Kentucky received a 14.5 composite score on the EXPLORE tests, compared with a national score of 14.9. The national PLAN composite score was a 17.5, and Kentucky students scored 16.4.

Fayette County's EXPLORE composite was 15.1; the district's PLAN composite was 17.8.

"This is the first time that we have this data," (my colleague and friend) Principal Jock Gum told the Herald-Leader. "It helps us to understand where deficiencies are as far as preparation for high school." Gum said that, unlike CATS, there was little pressure put on students because this is thought of as a diagnostic test.

The press release from KDE said, "...overall school scores are mid-range or higher." That comment prompted a retort from the Bluegrass Institute saying, "...the Kentucky Department of Education has lost no time in trying to spin below average results into “scores that are mid-range or higher.”

This is a definitional argument and a pretty good example of how data can be made to sing a certain song depending on one's orientation.

So in this case, who's correct? Well, they both are - to a point.

Every statistician on the planet understands that the mid-range of human performance is generally somewhere between the 40th and 60th percentiles. Some will describe mid-range as including all scores that are between one standard deviation below, and one standard deviation above the mean. This is a fair description of the EXPLORE and PLAN results, and KDE is not inaccurate in their description. But did they describe the data with a positive spin? You bet.

On the other hand, the scores are, in fact, below average (with the sole exception of 8th grade reading, which is exactly average) and the high school scores trail those of the middle school. Is it fair to say Kentucky's scores are generally below average? Yes, they are.

But let's not reinterpret Webster to say that "mid-range" is the same as "average." Mid-range is a set of scores that surround the mean. An average (the mean) is a single score.

Here are the data, courtesy of the Herald-Leader.