I have never run a controlled experiment before, so much of this reading was new to me. I was especially interested in the section about designing controlled experiments. The independent variable is intentionally varied, the dependent variable is measured (and kept constant?), and confounding variables are variables that are unintentionally varied and can change the results of the experiment (the values of the dependent variable). One can control for certain confounding variables like age, gender, and level of education, but it seems like a lot of planning must go into a controlled experiment to make sure things like time of day, or the place where the experiment is taking place do not become confounding variables. Conducting the experiment within subjects and between subjects is also a consideration. A within-subject experiment involves all participants and all conditions, which is somewhat like how we conducted our think alouds and paper prototyping. A between-subject experiment would involve one participant and one condition.
Adding these notes from class…
The Independent Variable is intentionally changed.
Ex. target… cheese or cracker?
The Dependent Variable is numeric, measured for the expeiment.
Ex. speed of rat from point A to point B in a maze
…as we manipulate the variable the speed will change
…same maze every time