DISCARD PILE

In the June 18 PopMeter column, you list the ratings of your six critics and then report the average, using that figure to rank the album. But what if a certain number of critics occasionally or permanently suffer from derangement, bias, stupidity or cupidity?

We statisticians have devised a safer method, called the trimmed mean, which is now used in many judgment situations such as figure-skating competitions.

Depending on the maximum number of “defective” judgments you wish to guard against, you throw away the one or two (or even more) highest and lowest scores and average only the remaining ones. The new averages are said to be more “robust” in the sense of being reliable in the face of severe data aberrations. If you wished to guard against a maximum of two defective results, for example, you would throw away the two highest and two lowest values and average the remaining (two).

The new trimmed means would give almost the same order for June 18’s albums, except that “Wowee Zowee” would now be slightly higher than “This Is How We Do It,” instead of finishing in a tie.

DAVID ROTHMAN

Hawthorne