Office of Naval Research
Grant #N000141010143
Grant #N000141310438

Publication: Searching for the two sigma advantage: Evaluating algebra intelligent tutors

The latest publication from ANGLE is now available.  The article, published in Computers in Human Behavior, describes the evaluation of two algebra intelligent tutoring systems in a remedial high school context.  Download the article’s final draft post-print here: Sabo et al. – 2013 – Searching for the two sigma advantage


Sabo, K. E., Atkinson, R. K., Barrus, A. L., Joseph, S. S., & Perez, R. S. (2013). Searching for the two sigma advantage: Evaluating algebra intelligent tutors. Computers in Human Behavior29(4), 1833-1840. doi: 10.1016/j.chb.2013.03.001


This study evaluated 2 off-the-shelf, computer-based, mathematics intelligent-tutoring systems that provide instruction in algebra during a remedial mathematics summer program. The majority of the enrolled high school students failed to pass algebra in the previous semester. Students were randomly assigned in approximately equal proportions to work with the Carnegie Learning Algebra Cognitive Tutor or the ALEKS Algebra Course. Using the tutoring system exclusively, the students completed a 4-hour-a-day, 14-day summer school high school algebra class for credit. The results revealed that both tutoring systems produced statistically and practically meaningful learning gains on measures of arithmetic and algebra knowledge.

Keywords:  intelligent tutoring systems, evaluation of CAL systems, applications in subject areas, evaluation methodologies, secondary education.