Ecological control group

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An ecological control group is a control group in an in vivo experiment that is the "as is" approach within the current course. The researcher is not free to choose the nature of the instruction in an ecological control, rather the instruction is determined by current practices in the course.

Having an ecological control group is one protection against choosing a control condition that might be judged as a "straw man" because it is too easy to improve upon and is not representative of standard practice.

In laboratory studies, a researcher is free to choose a control group, for instance, to be as close to the treatment condition as possible in all aspects but a single variable being changed. Such "tight controls" may sometimes be worse than current practice (i.e., the ecological control) and sometimes better.

In designing an in vivo experiment where current practice does not provide a tight control to test the target hypothesis, it is worthwhile to consider including both an ecological control as well as one or more tight control conditions. For instance, in the Rummel et al. study of scripting collaboration, the ecological control is a students working individually with the Algebra Cognitive Tutor as they usually do, the tight control is students working collaboratively in pairs without a collaboration script, and the treatment is students working collaboratively in pairs with a collaboration script.