Basic Experimental Design - Research Methods - Lecture Slides, Slides of Research Methodology

Download Basic Experimental Design - Research Methods - Lecture Slides and more Slides Research Methodology in PDF only on Docsity! Basic Experimental Design • Remember the principle of parsimony! • Two-group design – One independent variable – Two levels of the independent variable – Two independent groups formed, each receiving one level of the I.V. – T-test is appropriate statistical test Docsity.com Demonstrating cause and effect • Covariation/correlation shows relatedness • Directionality must be demonstrated (cause comes before the effect) • Elimination of extraneous variables Docsity.com Manipulating your I.V. • Consider doing a pilot test: try out levels of the I.V. on a few volunteers to see how they respond • Can also do a manipulation check at end of data gathering Docsity.com Try to keep all factors constant except your I.V. • Day of week, time of day, testing room • Instructions • Time to complete task • Watch out for subtle confounds! Docsity.com And remember to watch out for: • Differential mortality (dropout) • Experimenter expectancies • Demand characteristics • Placebo effects Docsity.com