[referring to Oliver, 21 Oct 96] I would have to say, based on your hypothetical experiment, that media does indeed matter very much . We have a perfect and traditional person X situation, or aptitude X treatment interaction, or media X individual, if you will in your example. The unique combination of both of these factors most certainly account for a significant amount of variance in students' scores. Also, as a teacher/trainer, the study has important implications. If I'm dealing with poor readers, I'd better think carefully about the type of media I use. It seems like what you're suggesting is that other factors are important beyond media--and I suspect Steve wouldn't disagree. This does not mean that the medium of delivery is not important. As Steve pointed out, he randomly assigned students to groups, so the probability that there was any systematic confounding variance based on verbal ability/reading is quite small, so I don't understand the suggestion regarding validity. I suppose he could have measured verbal ability/reading skill and used it as a covariant in his analysis; but, I suspect this would have not made a difference. Media doesn't matter? This seems like such a counterintuitive idea and is so inconsistent with my knowledge of educational psychology research where presentation format can have such a strong effect on learning (often interacting with learner variable, as you've pointed out, Jeff). Am I missing some important subtle (or not so subtle) point?
[quoting Cornell, 21 Oct 96] I still like Clark's metaphor of the grocery truck, I see his point, and subscribe to the basic premise that it is not the technology about which we should pay the most attention but the learning process. Technologies will come and go, learning keeps on keeping on.
THIS I understand, and, if this is the purpose of Clark's metaphor. I agree completely. Thank you for this enlightenment, Dick Cornell. By the way, I don't see this as an argument not to conduct research comparing media--only a warning to consider the results in context.
[quoting Wager, 21 Oct 96] If we buy the notion that learning is a function of the quality of the instruction, the learner's aptitude, the learner's learning strategies, the learner's motivation, and the amount of time allowed (John Carroll), we can see that the medium and the message are a part of a very complex equation. To simplify this to a "which one is best" question is to ignore the complexity of the "authentic" environment.
You simply have to design complex experiments (in my view).
I think the question is "what level of each is best within a given context?" I certainly don't think we should abandon the search for improving learning via both quantitative and qualitative methodologies--including media as an important part of the equation.