Key points are not available for this paper at this time.
John M. Braxton, Mardy T. Eimers, Alan E. Bayer, The Implications of Teaching Norms for the Improvement of Undergraduate Education, The Journal of Higher Education, Vol. 67, No. 6 (Nov. - Dec., 1996), pp. 603-625
Braxton et al. (Fri,) studied this question.