PR2-Q2-LESSON 1-EXPERIMENTAL RESEARCH.pptx

Experimental Research Design

1. Research Design (Experimental Research)

2. Learning Objectives: Define experimental research design Identify the key characteristics of experiments

3. Pretest: Identify whether the statement is TRUE or FALSE. 1. In experimental treatment, the researcher physically intervenes to alter the conditions experienced by the experimental unit (e.g., a reward for good spelling performance or a special type of classroom instruction, such as smallgroup discussion).

4. Pretest: Identify whether the statement is TRUE or FALSE. 2. The major characteristic of experimental research that distinguishes it from all other types of research is that researchers manipulate the independent variable.

5. Pretest: Identify whether the statement is TRUE or FALSE. 3. The experimental group receives a treatment of some sort while the control group receives no treatment (or the comparison group receives a different treatment).

6. Pretest: Identify whether the statement is TRUE or FALSE. 4. Random assignment means that every individual who is participating in an experiment has an equal chance of being assigned to any of the experimental or control conditions being compared.

7. Pretest: Identify whether the statement is TRUE or FALSE. 5. Experimental design is used to establish predictions and associations between two or more variables.

8. Pretest Answers: True True True True False

9. Experimental Research Design Experimental research is one of the most powerful research methodologies that researchers can use. Of the many types of research that might be used, the experiment is the best way to establish cause-and-effect relationships among variables. Yet experiments are not always easy to conduct .

10. What is an experiment? In an experiment, you test an idea (or practice or procedure) to determine whether it influences an outcome or dependent variable. You first decide on an idea with which to “experiment,” assign individuals to experience it (and have some individuals experience something different), and then determine whether those who experienced the idea (or practice or procedure) performed better on some outcome than those who did not experience it.

11. When Do You Use an Experiment? You use an experiment when you want to establish possible cause and effect between your independent and dependent variables. This means that you attempt to control all variables that influence the outcome except for the independent variable. Then, when the independent variable influences the dependent variable, we can say the independent variable “caused” or “probably caused” the dependent variable.

12. When Do You Use an Experiment? For example, if you compare one group that experiences a lecture and another group that experiences discussion , you control all of the factors that might influence the outcome of “high scores on a quiz.” You make sure that personal abilities and test conditions are the same for both groups, and you give both groups the same questions. You control for all variables that might influence the outcome except for the difference in types of instruction (lecture or discussion). You also use an experiment when you have two or more groups to study, as in this lecture versus discussion example.

13. When Do You Use an Experiment? For example, if you compare one group that experiences a lecture and another group that experiences discussion , you control all of the factors that might influence the outcome of “high scores on a quiz.” You make sure that personal abilities and test conditions are the same for both groups, and you give both groups the same questions. You control for all variables that might influence the outcome except for the difference in types of instruction (lecture or discussion). You also use an experiment when you have two or more groups to study, as in this lecture versus discussion example.

14. WHAT ARE KEY CHARACTERISTICS OF EXPERIMENTS? The major characteristic of experimental research that distinguishes it from all other types of research is that researchers manipulate the independent variable. They decide the nature of the treatment (that is, what is going to happen to the subjects of the study), to whom it is to be applied, and to what extent. Independent variables frequently manipulated in educational research include methods of instruction, types of assignment, learning materials, rewards given to students, and types of questions asked by teachers. Dependent variables that are frequently studied include achievement, interest in a subject, attention span, motivation, and attitudes toward school.

15. WHAT ARE KEY CHARACTERISTICS OF EXPERIMENTS?

16. WHAT ARE KEY CHARACTERISTICS OF EXPERIMENTS?

17. Some actual examples of the kinds of experimental studies • The effect of small classes on instruction. • The effect of early reading instruction on growth rates of at-risk kindergarteners. • The use of intensive mentoring to help beginning teachers develop balanced instruction. • The effect of lotteries on Web survey response rates. • Introduction of a course on bullying into preservice teacher-training curriculum. • Using social stories to enhance the interpersonal conflict resolution skills of children with learning disabilities. • Improving the self-concept of students through the use of hypnosis.

18. Example of Research Questions

19. Directions: Based on the hypothesis for each of the statements, identify the variables, control group, and experimental group.

20. Example: Cigarette smoking increases the risk of lung cancer. Hypothesis: If If you smoke cigarettes, then your chances of getting cancer increases Independent Variable: smoking cigarettes Dependent Variable: whether you get cancer Control Group: people who do not smoke Experimental Group: smokers

21. Eating breakfast increases performance in school Hypothesis: If If you eat breakfast, then you will get better grades Independent Variable: ______________ Dependent Variable:________________ Control Group: ____________________ Experimental Group:________________

22. 2. iBook batteries last for 5 hours. Hypothesis: If you use iBook batteries then your iBook will run for 5 years Independent Variable: ______________ Dependent Variable:________________ Control Group: ____________________ Experimental Group:________________

23. 3. Students who study perform better in school. Hypothesis: If a student studies then he/she will get good grades Independent Variable: ______________ Dependent Variable:________________ Control Group: ____________________ Experimental Group:________________

24. 4. Plants grow best in white light. Hypothesis: If plants are grown in white light then they will grow taller. Independent Variable: ______________ Dependent Variable:________________ Control Group: ____________________ Experimental Group:________________

25. Seat work Answers: 1. Independent Variable: breakfast Dependent Variable: grades Control Group: students who do not eat breakfast Experimental Group: students who take breakfast 2. Independent Variable: battery types Dependent Variable: time plays Control Group: different type of battery Experimental Group: :iBook battery 3. Independent Variable: studying Dependent Variable: grades Control Group: not studying Experimental Group: students who study 4. Independent Variable: type of plants Dependent Variable: height of plants Control Group : plants in different colors of light Experimental Group: :plants in white light