PS295 Chapter Notes - Chapter 10: Demand Characteristics
Document Summary
Simplest one way design is two group experimental design in which there are only 2 levels of iv and thus 2 conditions. Most experiments involve more than 2 levels of the iv. Ex studying single iv with 5 levels in weight loss studies. One way designs come in 3 basic varieties: randomized groups design, matched subjects design, repeated measures/within subjects design. Randomized groups design is a between subjects design in which participants randomly assigned to one of two or more conditions. Matched subjects design used to incease similarity of experimental groups prior to manipulation of iv. These 3 designs are posttest-only designs bc dependent variable is measured only after manipulation of iv has occurred. Pretest posttest designs used when researchers measure dv before and after iv. Posttest only designs are perfectly capable of identifying effects of iv as long as all groups were initially equivalent and most experiments use posttest only designs.
