Mike Bush shared the following resources from Dexter Fletcher that make reference to the 2-sigma problem.
The 2008 Educational Researcher piece, “Learning Anytime, Anywhere: Advanced Distributed Learning and the Changing Face of Education,” can be access online if you are on the BYU campus here. If you are off campus, you will have to authenticate or get access through your local library.
Fletcher, J. D. (1992). Individualized systems of instruction. In M. C. Alkin (Ed.), Encyclopedia of educational research (6th ed.,
pp. 613–620). New York: Macmillan.
Fletcher, J. D. (1997). What have we learned about computer-based instruction in military training? In R. J. Seidel & P. R. Chatelier (Eds.), Virtual reality, training’s future? (pp. 169-177). New York: Plenum.
Fletcher, J. D. (2004). Technology, the Columbus effect, and the third revolution in learning. In M. Rabinowitz, F. C. Blumberg, & H. Everson (Eds.), The design of instruction and evaluation: Affordances of using media and technology (pp. 139–157). Mahwah, NJ: Lawrence Erlbaum.
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