Web edition: October 28, 2004
Print edition: October 30, 2004; Vol.166 #18 (p. 287)
Speaking as someone with a Ph.D. in math who has spent most of his 30-year professional life unemployed and who can probably look forward to spending the rest of it unemployable, I was disappointed that "Where Ph.D.s pay off" in (SN: 8/7/04, p. 94: http://www.sciencenews.org/articles/20040807/note16.asp) made no apparent effort to find points of view other than the researchers'.
New York, N.Y.
People in government and industry tend to work all year. Academia employees, especially teachers, work only 34 to 35 weeks a year. That makes the academics' pay (about 70 percent of full-time pay) about right.
Richard P. Taylor
I wonder if the growth rings appearing in dinosaur bones ("Growth Spurt: Teenage tyrannosaurs packed on the pounds," SN: 8/14/04, p. 99: http://www.sciencenews.org/articles/20040814/fob1.asp) are analogous to those of trees, which are determined by the annual climatic cycle. Is it possible that the dinosaur rings were created on a different time cycle?
Researchers say that they haven't come up with another type of cycle that seems feasible.S. Perkins
Having just read "To Err Is Human" (SN: 8/14/04, p. 106: http://www.sciencenews.org/articles/20040814/bob9.asp), I want to add some comments. I led men in combat in World War II when we overran several concentration camps. My men held their anger, and not one went below the line to become an animal just because the other guy had. I'd like to point out that any group needs one strong leader. I say to researcher Zimbardo, put one good leader in charge of your experiments and see the difference.
Curtis R. Whiteway
"Regression to the mean" doesn't imply that the average of an individual's repeated test scores converges to the group mean, but rather that the average of each individual's repeated scores converges toward his or her individual mean and that the average of the group's repeated test scores converges toward the group mean.
Salt Lake City, Utah