If you're a student, a "good" question on an exam is one to which you know the answer. For teachers, however, it's not that simple. For teachers, a good question will tell you something about who's answering it.
If every student gets it wrong, or if every student gets it right, then it's a bad question. But if the good students tend to get it right, and the poor students tend to get it wrong, then a teacher can regard it as a good question because it accurately differentiates between the two groups.
This has nothing to do with travel, but it has everything to do with attempts to create a "cruise ship report card" about environmental practices, a favorite pastime of Friends of the Earth.
The report card, posted on the environmental group's website, grades 10 top cruise lines on things like air pollution and water quality practices. What stands out on the report card is that seven of the 10 cruise lines failed on air pollution, and one got a D. That struck us as odd. We wondered if maybe this was the result of a bad question.
Delving into the fine print, we discovered that the grade on air pollution reflected only one criterion -- in effect, one question: whether the cruise line has retrofitted its ships to plug in to available shore-side electrical power instead of generating their own power when in port.
That's it, the sole criterion. There was no attempt to differentiate between ships whose engines pollute a lot and those that pollute less, or to give A's to newer ships that might have the latest pollution technology.
It all came down to one question.
And it was a curious question, given that there are only five berths in all of North America where cruise ships can tap the local power grid in the first place.
This is the sort of thing that led CLIA to complain, rightly, that the report card was based on "arbitrary and flawed criteria" rather than on science.
CLIA's two dozen cruise line members operate hundreds of ships, and we have no doubt that some of them are greener than others, but the so-called report card from Friends of the Earth offers no meaningful guidance to travelers or travel agents who might want to cruise on ships that exceed this or that standard rather than ships that just meet those standards.
That would be a good exam. This wasn't.