Dear Linda,
Are you sure that the graph has IQ scores on the y-axis? There is plenty of cross-sectional data showing that raw scores show the pattern you describe. Your astute student is logically correct. If scores in each age group are age-normed, average scores have to be flat! Stuart ______________________________________________ Stuart J. McKelvie, Ph.D., Department of Psychology, Bishop's University, 2600 College Street, Sherbrooke, Québec J1M 0C8, Canada. E-mail: [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> or [EMAIL PROTECTED] Phone: (819)822-9600, Extension 2402 Fax: (819)822-9661 Bishop's Psychology Department Web Page: http/:www.ubishops.ca/ccc/dev/soc/psy __________________________________ ________________________________ From: Tollefsrud, Linda [mailto:[EMAIL PROTECTED] Sent: Thursday, April 05, 2007 3:20 PM To: Teaching in the Psychological Sciences (TIPS) Subject: [tips] IQ and age-norming question My Lifespan Development text says, in the intelligence chapter, "The concept of mental age is no longer used . . . individuals receive scores that reflect how well or how poorly they do as compared with others of the same age." However, later in the chapter, a graph of IQ scores over the lifespan indicates a gradual rise in IQ from 16 to about 40, then a gradual decline from 40 through the 80s. A student pointed out the apparent contradiction here: if IQ scores are normed by age group, how can we graph the changes from age group to age group? I was not able to give a good answer (apparently because I don't have a good answer). I tried a Google Scholar search. The closest I found was a comment from a 2002 Psych Review article by Garlick that includes this quote, " . . mental age . . appeared to cease to develop . . at about the age of 16 years. Thus, originally, any person older than 16 years was taken to have a chronological age of 16 when calculating their IQ score." I assume that 16 is not currently the "norm" for all adults, but still have many questions about how the norming is done. Is there a relatively brief answer out there in TIPS land? Linda Tollefsrud Professor of Psychology University of Wisconsin - Barron County 1800 College Drive Rice Lake, WI 54868 (715) 234-8176 [EMAIL PROTECTED] --- To make changes to your subscription go to: http://acsun.frostburg.edu/cgi-bin/lyris.pl?enter=tips&text_mode=0&lang=english --- To make changes to your subscription go to: http://acsun.frostburg.edu/cgi-bin/lyris.pl?enter=tips&text_mode=0&lang=english
