Posttest results of the assessment experiment, comparing the standard and double
transfer paradigms. A quantitatively correct answer received a score of 2, a qualitatively correct
answer (including graphing) received a score of 1, and all other answers received a score of 0. The
posttest scores are adjusted by using the pretest scores as covariates. (The unadjusted posttest
means may be computed from Table 2.) Error bars reflect the standard error of each mean.