Research Approach

1. Research Approach Qualitative Quantitative Experimental Pre experiment Ex Post Facto True Experiment Correlational Quasi Experiment Survey EDU 5900 AB RAHIM BAKAR

2. Types of Research Purpose or end sought EXPLORE DESCRIBE EXPLAIN- PREDICT CONTROL Descriptive [PRE EXPERIEMNTAL] SURVEY RESEARCH TRUE EXP & QUASI EXP CORR & EX POST EDU 5900 AB RAHIM BAKAR

3. Research Approach Qualitative Quantitative Experimental Pre experiment Ex Post Facto True Experiment Correlational Quasi Experiment Survey EDU 5900 AB RAHIM BAKAR

4. Experimental Research Designs have Two Purposes: • …to provide answers to research questions • ...to control variance (differences) EDU 5900 AB RAHIM BAKAR

5. The main function of the experimental research design is to control variance. • Principle: maximize systematic variance, control extraneous systematic variance, and minimize error variance. • MAX-MIN-CON In other words control variance. EDU 5900 AB RAHIM BAKAR

6. Therefore the researcher attempts to: • maximize the variance of the variable(s) of the research hypothesis (i.e., maximize the difference in the dependent variable [outcome] caused by maximizing the differences in the independent variable [treatment]). • control the variance of extraneous or "unwanted" variables that may have an effect on the experimental outcomes, but which he/she is not interested (limit factors other than the treatment (IV) that could be causing differences in the outcome (DV) . • minimize the error or random variance (i.e., avoid unreliable measurement instruments which have high errors of measurement ). EDU 5900 AB RAHIM BAKAR

7. Maximization of Experimental Variance experimental variance the variance due to the manipulated (i.e., treatment) or attribute (i.e., gender) variables (IV) research precept: design, plan and conduct research so that experimental conditions are as different as possible on the independent variable. EDU 5900 AB RAHIM BAKAR

8. Maximization of Experimental Variance experimental variance the variance due to the manipulated (i.e., treatment) or attribute (i.e., gender) variables (IV) research precept: design, plan and conduct research so that experimental conditions are as different as possible on the independent variable. EDU 5900 AB RAHIM BAKAR

9. Minimizing Error Variance has Two Principle Aspects: • reduction of errors of measurement through controlled conditions (i.e., standardize testing procedures) • increase in the reliability of measures (i.e., revise test instruments or find more reliable ones) EDU 5900 AB RAHIM BAKAR

10. Experimental Designs Three types of experimental research designs: • pre-experiment, • true experimental and • quasi-experimental. EDU 5900 AB RAHIM BAKAR

11. These designs are generally used to determine cause and effect. They allow us to make inferences. According to David Hume, there are three criteria to be met to infer causality: Contiguity between the presumed cause and effect. In other words, the causal variable (independent) and the effect variable (dependent) must be associated. Temporal Precedence. In other words, the cause must precede effect. Constant conjunction. In other words, the cause is present whenever the effect is obtained. EDU 5900 AB RAHIM BAKAR

12. All experiments involve treatment outcome units of assignment comparison from which change can be inferred and attributed to the treatment. EDU 5900 AB RAHIM BAKAR

13. Characteristics of True Experiments Manipulation • The experimenter does something to at least some of the subjects in the experiment. The introduction of that something is often referred to as the experimental treatment or experimental • Intervention. This is also known as the independent variable. The researcher manipulates this independent variable by administering it to some subjects and withholding it from other subjects. In other words, the experimenter varies the independent variable and observes the effect that the manipulation has on the dependent variable of interest. EDU 5900 AB RAHIM BAKAR

14. Control Control summarizes all of the major experimental activities. They are manipulation, use of comparison (control) groups, and randomization. Campbell and Stanley (1963) observed that obtaining scientific evidence requires at least one comparison. Control groups are used for this purpose. The term control group refers to the subjects that do not receive the experimental treatment and their performance on the dependent variable serves as a basis for evaluating the performance of the experimental group (the group who received the experimental treatment) on the same dependent variable. EDU 5900 AB RAHIM BAKAR

15. Randomization The assignment of subjects to groups on a random basis. The term random essentially means that every subject has an equal chance of being assigned to any group. The intent is to equalize the groups however, there is no guarantee that the groups will be equal. The chance of obtaining unequal groups diminishes as the sample size increases. Researchers generally use a table of random numbers to facilitate the randomization EDU 5900 AB RAHIM BAKAR

16. Strengths of the Experimental Design • Some researchers believe that this is the most powerful research design as it gives us cause and effect relationships. • If we do this then we can expect that. This if-then relationship is important to those health care practitioners who want to predict and control. • Therefore the strength lies in the fact that causal relationships can be inferred. • This is not without controversy. Some scholars believe that the notion of causality among phenomenon is untenable. EDU 5900 AB RAHIM BAKAR

17. Weakness of the Experimental Design • There are a number of variable of interest that are not amenable to manipulation. For instance we cannot randomly confer upon infants their weight at birth to observe the effect of birth weight on subsequent morbidity. • Ethical considerations may prevent the manipulation of the independent variable. You would not inflict pain for the sake of an experiment. • Artificial circumstances may affect the results. Laboratory designs take place in an artificial setting. Easier to control for external variables and is not as generalizable because it constrains the human experience. Field designs take place in the actual setting and may be better but there are more problems with controls. • The Hawthorne Effect: effect of being in the study group may be sufficient to cause people to change their behaviors. This is the reason that double blind studies are conducted. In which neither subject nor those who administer the treatment knows which is the experimental or control group. EDU 5900 AB RAHIM BAKAR

18. Pre-Experimental Designs 1. One-Shot Case Study X O   2. One-Group Pretest-Posttest Design O1 X O2   3. Static-Group Comparison or Intact- GroupComparison X O1 or X1 O1 ------ ------- O2 X2 O2 EDU 5900 AB RAHIM BAKAR

19. One shot case study ( X O) satu kumpulan diberikan treatment atau didedahkan kepada suatu jenis treatment kemduain pengukuran dilakukan. Misalnya try to determine the effect of a new teksbook on pencapaian dalam peperiksaan X O New textbook pencapaian Tiada kawalan; no comparison (O1) yang ada hanyalah O2; no pretest score (O1) Jadi tak pasti samada O di sebabkan oleh X So, what causes O? Tak pasti lagi! EDU 5900 AB RAHIM BAKAR

20. One-group pretest-posttest design O1 X O2 Still no control group. Tapi tahu ada perubahan atau tidak kerana ada maklumat awal mengenai pencapaian subject berkenaan (pretest score). Need to have a comparison group yang tak dapat treatmeNt yang sama. belum boleh buat andaian lagi bahawa perubahan disebabkan oleh X EDU 5900 AB RAHIM BAKAR

21. What are the threats to internal validity posed by this design? Almost all!! Except selection & mortality. History? Events that may occur between the two observations Maturation > biological and psychological (grow older, tired, bored etc) Testing > Instrument decay > perubahan yang sengaja atu tidak sengaja (oberver/interviewer) EDU 5900 AB RAHIM BAKAR

22. STATIC GROUP COMPARISON X1 O1 inquiry Ujian ------------------------ X2 O2 lecture ujian Gunakan dua atau lebih kumpulan eksperimen Existing group or intact group (2 classrooms) No randomization of subjects to groups. Sebab tak boleh nak randomized. Existing group or intact group (2 classrooms) No randomization of subjects to groups. Sebab tak boleh nak randomized. EDU 5900 AB RAHIM BAKAR

23. Banyak digunakan dalam penyelidikan pendidikan Berikan treatment yang berbeza (kaedah mengajar inquiry to group A dan lecture to group B) Administrative performance of principals with bachelor degree and principals with Masters degree. Any internal validity threats? Khususnya selection and mortality. What selection? No random assignment of subjects to groups. Differences of subject characteristics. EDU 5900 AB RAHIM BAKAR

24. True experimental designs include: -pre-test/post-test control group design -Solomon four-group design -post-test only control group design EDU 5900 AB RAHIM BAKAR

25. Pretest-Posttest Control Group Design R O1 X O2 or R O1 X1 O2 R O3 O4 R O3 X2 O4 which can easily be extended to R O1 X1 O2 R O3 X2 O4 R O5 X3 O6 R O7 X4 O8 EDU 5900 AB RAHIM BAKAR

26. The pre-test-post-test experimental design is more complex. It is called pre-test-post-test because there are two points of measurement, one before the experimental treatment and one after the experimental treatment. Example: Suppose we wanted to examine the effect on the heart rate of being restrained. The design would involve imposing a posey belt on the experimental group and no posey belt on the control group. The dependent variable which is the heart rate would be measured at two points in time. Before the posey belt and after the posey belt. This allows us to examine if heart rate changes were produced as a result of being restrained. EDU 5900 AB RAHIM BAKAR

27. Kawal kesemua threats to internal validity Kenapa ada prestest? Means of checking if both groups are similar & assess if changes occur due to treatment not because of existing factors Dapatkan perbezaan skor ( O2 - O1) dan (O4 - O3). Jalankan ujian t atau anova (?) untuk uji hipotesis yang mengatakan treatment tidak ada kesan ke atas pencapaian. EDU 5900 AB RAHIM BAKAR

28. Randomize Posttest-Only Control Group Design R X O1 or R X1 O1 R O2 R X2 O2 which can easily be extended to R X1 O1 R X2 O2 R X3 O3 R X4 O4 EDU 5900 AB RAHIM BAKAR

29. The post-test only experimental design is a simple design. It is called post-test only because the data is collected after the experimental treatment is complete. Example: Hypothesis is that the color of a pediatric nurses uniform affects the degree to which children display positive and negative affective behavior (laughing, crying). The causative or independent variable is the uniform color and the effect variable or dependent variable is the child’s behavior. The independent variable is manipulated by assigning some nurses white uniforms and some nurses colored uniforms. Thus, in this study we could compare the affective behaviors of children cared for by nurses in white uniforms and those cared for nurses in colored uniforms. EDU 5900 AB RAHIM BAKAR

30. Subject di tempatkan dalam kumpulan secara random Control for selection, maturation, statistical regression, testing. May not control mortality- drop out> why drop out? report berapa bilangan subject yang drop out Drop out cuase dissimilarity of the groups Instrumentation, history may still be the threats Example of a study using this design? Perhaps of all design to use if we have 40 subjects in each group (Frankael & Wallen, 1990) EDU 5900 AB RAHIM BAKAR

31. Solomon Three-Group Design • Three groups are involved • Overcoming the difficulty in Pretest-Posttest Control Group Design [effect pf pretesting and treatment] • A second control group [C2) is not pretested but exposed to treatment • Compare the Y2 of the three groups to see if treatment really made the difference • You can check of the interaction effect between pretest and treatment….. EDU 5900 AB RAHIM BAKAR

32. SOLOMON THREE GROUP DESIGN EDU 5900 AB RAHIM BAKAR

33. Solomon Four-Group Design R O1 X O2 or R O1 X1 O2 R O3 O4R O3 X2 O4 R X O5R X1 O5 R O6R X2 O6 Rekabentuk ini merupakan modifikasi posttest only control group or pretest-posttest control group (Frankel & Wallen, 1990) yang membolehkankan kita melihat kesan pembolehubah tambahan EDU 5900 AB RAHIM BAKAR

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35. The Solomon four-group design is a version of the pre-test-post-test design. It adds two addition groups. The purpose of adding the two groups is to separate the effects of the pre-test and to segregate it from the intervention.. In other words, a pre-test may be a sensitizing treatment that may affect the results of an actual treatment. 1 is an experimental groups without the pretest 1 is the control group without the pre test Example: If our intervention was a workshop to improve nurses attitudes toward alcoholic patients, the pre-test may sensitize the nurses and affect their attitudes at that point and obscure the analysis of the workshop’s effect. EDU 5900 AB RAHIM BAKAR

36. Usaha untuk menghapuskan kemungkinan kesan pretesting Random assignment of subjects to four groups. Dua mendapat pretest dan dua lagi tidak. Kesemuanya akan diposttest Better control for IV threat but require larger sample and a lot of hard work Have to conduct two experiments simultaneously EDU 5900 AB RAHIM BAKAR

37. Strength of Solomon Four Group Design Incorporate strengths of design Solomon Three Group Design and Randomized Pre and Posttest Designs, Randomized Posttest Only Control Group Design Can make several comparison to determine the effect of the treatment EDU 5900 AB RAHIM BAKAR

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39. Factorial designs • Two or more variables are manipulated simultaneously in order to study the independent effect of each variable on the dependent variable as well as the effect caused by interaction of several independent variables • We can have the design whereby we manipulate only one independent variables or more than one independent variables EDU 5900 AB RAHIM BAKAR

40. Simple factorial design The interest is on the effect of a single independent variable but must also consider other variable that may influence the dependent variable. Typically these variables are attribute variable such as race, gender, SES, etc. Enable the researcher to study several relationship with one set of data Able to study interaction between variables EDU 5900 AB RAHIM BAKAR

41. The simplest factorial design is 2 X 2 Factorial Design. Here you have two independent variables with two levels each EDU 5900 AB RAHIM BAKAR Example A

42. In example, the inquiry method is shown to be superior in both small and large classes. Hence there is no interaction effect. Regardless of class size, inquiry method is superior than lecture method. There is no interaction 50 46 45 inquiry What is interaction effect? The effect obtained may be differ for a different group. The result is moderated by another variable 40 40 38 35 lecture 30 32 small large EDU 5900 AB RAHIM BAKAR

43. Example B EDU 5900 AB RAHIM BAKAR

44. Studenst did better in small class than in large Class with both methods. However, students in small Class did better when taught Using inquiry method. Students in large class Did better when taught using Lecture method. Here there is an interaction between Class size and teaching methods 50 48 45 inquiry 42 40 38 lecture 35 30 32 small large EDU 5900 AB RAHIM BAKAR

45. Even though students in small class did better than those in large class, how well depends on the method used. As a result the researcher may conclude that effectiveness of the method is dependent on the class size. There is an interaction between class size and methods If factorial design was not used, you may conclude that there is no effect of method on achievement (40, 40) EDU 5900 AB RAHIM BAKAR

46. You can have a more complicated factorial design such as n BY n Factorial Design Example: (1) CAI, (2) Lecture-Discussion (3) Television Lecture (4) Quite Reading Moderator variable : (1) small class and (2) large class. 3X3 or 4X2 or 3X2 EDU 5900 AB RAHIM BAKAR