Chapter 8: Experimental Research

Front 1

What type of research is conducted in most disciplines?

Back 1

experimental research.

It is virtually the only type of research performed in the sciences.

Front 2

why is experimental research conducted?

Back 2

to increase the body of knowledge in a discipline and to suggest what procedures should be followed in the future.

Front 3

What does experimental research always involve?

Back 3

manipulation of the experimental unit.

Front 4

what is the purpose of experimental research?

Back 4

investigate the cause-and-effect relationship by subjecting experimental groups to treatment conditions and comparing the results to control groups not receiving the treatment.

Front 5

List the 14 systematic stages used in experimental research.

Back 5

1. state research problem

2. determine if the experimental approach is appropriate

3. specify the independent variable(s) and the levels of the independent variable(s).

4. specify all the potential dependent variables. Dependent variables

5. state the tentative hypothesis

6. determine the availability of measures for the potential dependent variables

7. pause to consider the success potential of the research

8. ID the full potential of intervening variables

9. make a formal statement of the research hypothesis

10. design the experiment

11. make a final estimate of the success potential of the study

12. conduct the study as planned in number 1 and 11.

13. analyze the data according to the data analysis plan

14. prepare a research report.

Front 6

define internal validity

Back 6

validity of the findings within or internal to the research study.

Front 7

define external validity

Back 7

validity of generalizing the findings in a research study to other groups and situations.

Front 8

list two classifications of validity

Back 8

1. internal validity

2. external validity

Front 9

what type of validity is concerned with whether the findings for the sample of participants in the study can be inferred to the population they represent and to other populations?

Back 9

external validity

Front 10

list the types of threats to internal validity

Back 10

1. History

2. Maturation

3. Testing

4. Instrumentation

5. Statistical regression

6. Selection

7. Experimental Mortality

8. Interaction of Selection and Maturation or History

Front 11

list the types of threats to external validity

Back 11

1. Interaction Effect of testing

2. Interaction Effects of Selection Bias and Experimental Treatment

3. Reactive Effects of Experimental Setting

4. Multiple-Treatment Interference

Front 12

define the meaning of history in internal validity

Back 12

refers to specific things that happen while conducting the research study that affect the final scores of the participants in addition to the effect of the experimental treatment.

ex. participant workout out outside of the experimental treatment and study could effect final results.

Front 13

define maturation in internal validity

Back 13

because participants grow older during the experimental period, performance levels change.

Front 14

define testing in internal validity

Back 14

the act of taking a test can affect the scores of the participants on a second or later testing. Participants may do better on a posttest because they learn from the first test.

Front 15

define instrumentation in internal validity

Back 15

changes in adjustment or calibration of the measuring equipment or use of different standards among scorers may cause differences among groups in final score.

check accuracy of measuring equipment routinely, and make sure standard scoring procedure is used. Testing and score procedures must be held constant.

Front 16

define statistical regression in internal validity.

Back 16

the tendency for groups with extremely high or low scores on one measure to score closer to the mean score of the population on a second measure.

Front 17

what can eliminate the threat of statistical regression?

Back 17

random sampling

Front 18

define selection in terms of internal validity.

Back 18

the way that participants were selected or assigned to groups can be biased.

Front 19

what controls for the selection threat in internal validity?

Back 19

random selection or participants and random assignment of participants to groups.

Front 20

define experimental mortality in internal validity

Back 20

created with excessive loss of participants so that experimental groups are no longer representative of a population or similar to each other.

when groups become different in size, it is a concern.

Front 21

define internal selection and maturation or History in internal validity.

Back 21

the maturation effect or history effect is not the same for all groups selected for the research study, and this influences final scores.

Front 22

what are the threats to external validity?

Back 22

1. Interaction Effect of Testing

2. Interaction Effects of Selection Bias and Experimental Treatment

3. Reactive Effects of Experimental Setting

4. Multiple-Treatment Interference

Front 23

define interaction effect of testing in external validity

Back 23

occurs when the pretest changes the groups response to the experimental treatment, thus making the group unrepresentative of any particular population.

Front 24

define interaction effects of selection bias and experimental treatment in external validity.

Back 24

participants or groups selected in biased manner react to the experimental treatment in a unique way so they are not representative of any particular population.

can easily occur when convenience is used.

Front 25

define reactive effects of experimental treatment.

Back 25

the experimental setting is such that the experimental treatment has a unique effect on the participants or groups that would not be observed in some other setting.

examples:

- participants react to researcher in unique manner

- conducting research in a lab, rather than natural setting

Front 26

define multiple-treatment interference in external validity

Back 26

the effect of prior treatments on the response of the participants or groups to a present treatment.

Front 27

how should the multiple-treatment interference threat be controled?

Back 27

researchers should check on the background and experiences of potential participants to control this threat to external validity.

Front 28

define designs

Back 28

the ways a research study may be conducted.

Front 29

what types of experimental designs are listed in the book?

Back 29

1. Preexperimental design

2. true experimental design

3. Quasi-experimental design

Front 30

define pre-experimental design

Back 30

designs that have poor control often due to no random sampling.

Front 31

define true experimental design

Back 31

the best type of design because there is good control with sufficient random sampling.

Front 32

define control goup

Back 32

in a research study, the group which received no treatment which should change its ability.

Front 33

define quasi-experimental design

Back 33

an acceptable design but with some loss of control due to lack of random sampling.

Front 34

what is a better design? preexperimental or quasi-experimental design?

Back 34

quasi-experimental.

Front 35

what is an example of a quasi-experimental design?

Back 35

the nonequivalent control group design. Like pretest/posttest control group design but except participants are not assigned to groups by using random sampling.

Front 36

What does a quasi-experimental control for?

Back 36

threats to validity of history, maturation, testing, instrumentation, selection, and experimental mortality.

Front 37

what threats does a quasi-experimental design not control for?

Back 37

threats to validity of the interaction effects of maturation and history, or the interaction effect of testing.

Front 38

designs can be discussed in terms of what two things?

Back 38

1. complexity

2. ability to answer research questions. Simple designs answer one question and more complex designs answer several research questions.

Front 39

why are preexperimental designs weaker than true experimental designs in terms of control?

Back 39

1. no random sampling of participants

2. are usually one group or two unequated groups

3. control few threats to validity

Front 40

give an example of a preexperimental design.

Back 40

1.one-group pretest/posttest design

2.the use of intact classes

Front 41

if the treatment groups are unequal at the end of the study in a preexperimental design, it could be due to...

Back 41

1. treatment were not equally effective

2. the groups were unequal at the start of the study

3. some combination of the two

Front 42

A design must do what?

Back 42

- control for major threats to validity.

- allow the researcher to answer the research question

- Follow KISS principle

- design must be adequate, but don't make the design any more complicated than it needs to be.

Front 43

what is the basic procedure, from the design stand point, if there are two or more groups?

Back 43

1. define the target population

2. ID the accessible population

3. randomly select participants

4. randomly assign participants to groups

Front 44

is maximal internal or external validity obtained in most studies?

Back 44

no, due to constraints on finances, time, participants, the research setting or other resources.

Front 45

what is a must in order to have good external validity.

Back 45

good internal validity

Front 46

True of false: Sometimes minor threats and threats that are hard to eliminate may have to be left uncontrolled.

Back 46

True

Front 47

In an experimental design, what does a research want to control?

Back 47

Control the effect of all variables except the experimental variable.

Front 48

List the ways in which the control of variables can be obtained?

Back 48

1. Physical manipulation

2. Selective manipulation

3. Matched pair design

4. Block design

5. Counterbalanced design

6. statistical techniques

Front 49

define selective manipulation

Back 49

method of gaining control by selectively manipulating certain participants or situations

Front 50

define matched pairs design

Back 50

a form of selective manipulation by which participants are matched to gain control

Front 51

define block design

Back 51

an extension of matched pairs design for three or more groups

Front 52

define statistical techniques

Back 52

method of gaining control if other control techniques are not possible

Front 53

define analysis of covariance (ANOVA)

Back 53

a statistical technique to gain control by adjusting for initial differences among groups

Front 54

define covariate

Back 54

score used to adjust for initial differences among groups in ANCOVA

Front 55

define variate

Back 55

the score adjusted in ANCOVA

Front 56

what are forms of selective manipulation?

Back 56

1. Matched Pairs

2. block design

3. counterbalance design

Front 57

what is an example of a counterbalance design?

Back 57

comparison of the effectiveness of two drugs.

Front 58

when are statistical techniques employed in order to gain control?

Back 58

when physical manipulation or selective manipulation of variables is not possible.

the researcher knows at the beginning of a study that the experimental groups differ in terms of one or more variables.

Front 59

what is the basic purpose of the ANCOVA?

Back 59

adjusts for the differences among the groups in scores at the end of the study based on differences in initial ability.

Front 60

When using the ANCOVA technique, what is obtained at the beginning of the study?

Back 60

- a covariate

- used to adjust differences among groups in terms of a score, called the variate, collected at the end of the study

Front 61

list the common sources of error in research.

Back 61

1. Hawthorne Effect

2. Placebo Effect

3. "John Henry" Effect

4. Rating Effect

5. Experimenter Bias Effect

6. Participant-Researcher Interaction Effect

7. Post Hoc Error

Front 62

define hawthorne effect

Back 62

participants in an experiment may perform in an atypical manner due to the newness or novelty of the treatment and because they realize that they are participating in an experiment.

Front 63

define placebo effect

Back 63

participants in an experimental treatment may believe the treatment is supposed to change them so they respond to the treatment with a change in performance.

Front 64

define placebo

Back 64

a treatment that can have no effect on any dependent variable of participants in a control group.

Front 65

define "john henry" effect

Back 65

in studies with an experimental group and a control group, the control group knows it is not supposed to be better than the experimental, so it tries harder and outperforms the experimental group

Front 66

define rating effect

Back 66

1. halo effect

2. central tendency error

Front 67

define halo effect

Back 67

the tendency to let initial impressions influence future ratings or scores of a participant

Front 68

define central tendency error

Back 68

a tendency to rate most participants in the middle of the rating scale.

Front 69

what can the halo effect cause?

Back 69

1. overrater error

2. underrater error

- researcher tends to overrate or underrate participants

Front 70

define experimenter bias effect

Back 70

the bias of a researcher can affect the outcome of study. The bias often favors the experimental treatment

Front 71

define single-blind study

Back 71

a study in which participants are unaware of the purpose of the study and their role in the study.

Front 72

define double-blind study

Back 72

a study in which participants and those conducting the study are unaware of the purposed of the study and group membership participants.

Front 73

define participant-researcher interaction effect

Back 73

- whether participants respond better to the same gender

- whether or not a certain setting may influence a participant

Front 74

define post hoc error

Back 74

caused by assuming a cause-and-effect relationship between two variables when such a relationship does not exist.

ex. most people die in bed than any other place; therefore, beds are dangerous.