Experimental Research Methods: Design, Validity, and Applications, Slides of Introduction to Sociology

Download Experimental Research Methods: Design, Validity, and Applications and more Slides Introduction to Sociology in PDF only on Docsity! CHAPTER 8, experiments docsity.com Chapter Outline Topics Appropriate to Experiments The Classical Experiment Selecting Subjects Variations on Experimental Design An Illustration of Experimentation Web-Based Experiments “Natural” Experiments Strengths and Weaknesses of the Experimental Method Ethics and Experiments Quick Quiz docsity.com The Classical Experiment • Major Components 1. Independent and Dependent Variables 2. Pre-testing and Post-testing 3. Experimental and Control Groups docsity.com • Independent and Dependent Variables – Independent – Takes the form of a stimulus (present or absent), cause – Dependent - Effect docsity.com • Pre-testing – The measurement of a dependent variable along subjects. • Post-testing – The measurement of a dependent variable among subjects after they have been exposed to an independent variable. docsity.com • Hawthorne Effect docsity.com • The Double-Blind Experiment – An experimental design in which neither the subjects nor the experimenters know which is the experimental and which is the control group. docsity.com Selecting Subjects * Role of college students * Generalizability? ® docsity.com Variations on Experimental Design • Pre-experimental Research Designs – One-shot case study – A single group of subjects is measured on a dependent variable following an experimental stimulus. – One-group pre-test post-test design – A pre-test is added for the experimental group but lacks a control group. – Static-group comparison – Includes experimental and control groups, but no pre-test. docsity.com Figure 8.3 eeu) One-Shot Case Study Aman who exercises is observed to be in trim shape Some intuitive standard of what constitutes a trim shape Time t Time 2 One-Group Pretest-Posttest Design === Comparison An overweight man who QO exercises is later observed — to be in trim shape i; —— Time f Static-Group Comparison Aman who exercises is observed to be in trim shape whereas one who doesn't is observed to be overweight Comparison Time 1 Time 2 Time 3 . docsity.com Validity Issues in Experimental Research Internal Validity – The possibility that the conclusions drawn from experimental results may not accurately reflect what went on in the experiment itself. Sources: history, maturation, testing, instrumentation, statistical regression, selection bias, experimental mortality, causal time order, diffusion or imitation of treatments, compensation, compensatory rivalry, demoralization External Validity – The possibility that conclusions drawn from experimental results may not be generalizable to the “real” world docsity.com An Illustration of Experimentation • Field Experiments docsity.com Web-Based Experiments • Representative samples are not essential…therefore, volunteers may be used. docsity.com |’” “Natural” Experiments ¢ Experiments that occur outside controlled settings. docsity.com 1. In the simplest experimental design, subjects are measured in terms of a/n _____ variable exposed to a/n _____ variable. A. pre-test; post-test B. post-test, pre-test C. independent; dependent D. dependent; independent docsity.com Answer: D. In the simplest experimental design, subjects are measured in terms of a dependent variable exposed to an independent variable. docsity.com 2. _____ groups are groups of subjects to whom an experimental stimulus is administered. A. Control B. Experimental C. Purposive D. Pre-test docsity.com Answer: C. Randomization is a technique for assigning experimental subjects to experimental and control groups randomly. docsity.com 4. Experiments are especially well-suited for research projects involving: A. limited concepts B. well-defined concepts C. hypothesis testing D. all of the above choices docsity.com Answer: D. Experiments are especially well-suited for research projects involving limited concepts, well-defined concepts, and hypothesis testing. docsity.com 6. Which of the following is the chief advantage of a controlled experiment? A. They require little time. B. They require little money. C. They are artificial. D. The experimental variable is isolated. docsity.com Answer: D. The isolation of the experimental variable is the chief advantage of a controlled experiment. docsity.com