UNIT 3
In Professor John's three week experiment, the control group has realized that the experimental group is being exposed to lavish lunches as part of the experiment, while they are stuck with plain microwaved meals. In protest, they have decided to stop full participation. Which form of internal invalidity does Professor John have to worry about?
Demoralization
You were asked to participate in an experiment to test the effectiveness of review sessions on exam grades. As a research methods student, you concluded that you had been assigned to the control group because you simply took the scheduled exams. Since you were in the control group you simply gave up and quit studying. This exemplifies:
Demoralization
Among the requirements for the classical experimental design is a posttest measurement of the:
Dependent variable for both the experimental and control groups
Experiments are especially appropriate for research projects involving all of the following EXCEPT: - Small-group interaction - Hypothesis testing - The testing of relatively limited and well-defined concepts and propositions - Descriptive research
Descriptive research
In order to ensure that experimental and control groups are similar before the experiment begins, social scientists sometimes: - Pair subjects who are identical on relevant variables and assign one to the control group and one to the experimental group - Randomly assign subjects to the experimental and control groups - Match subjects on relevant variables - Engage in activities mentioned in all of these choices
Engage in activities mentioned in all of these choices
Because experiments focus on determining causation, they are better suited to descriptive purposes rather than explanatory purposes.
False
Researchers tend to use probability sampling to recruit subjects for the experimental and control groups.
False
An interaction between the testing situation and the experimental stimulus jeopardizes generalizability.
True
The classical experimental design:
helps guard against the sources of internal invalidity
An experiment examines the effect of the:
independent variable on the dependent variable
The Solomon four-group design utilizes how many control groups?
2
A researcher administered a math test to a group of 9th graders in September. During the school year these students received an intensive program designed to improve their math skills. In May the math test was again given to these students and their math scores improved. A major problem in this research is that the researcher failed to control for: - History - Maturation - Testing - All the above
All the above
The Solomon four-group design:
Combines the classical experimental design with the posttest-only control group design
Which of the following would constitute a "natural" experiment? - Conducting a survey of city park workers regarding their job satisfaction - Doing a comparative analysis of families that choose to stay and those who choose to move out of a racially changing neighborhood to find out the underlying causes for the difference in their choices - Evaluating a drug courts program on drug user relapses - Presenting half of a classroom with a documentary on discrimination, then measuring student opinions on race
Doing a comparative analysis of families that choose to stay and those who choose to move out of a racially changing neighborhood to find out the underlying causes for the difference in their choices
The dependent variable is also known as the experimental stimulus.
False
The use of an experimental group allowss the researcher to control for the effects of the experiment itself
False
Typically, research on the World Wide Web involves representative samples.
False
The double-blind experiment is one in which:
Neither the subjects in the experimental or control groups nor the experimenters know which are the experimental and control groups
Kyo is looking to perform a quick research study to determine the effects of a documentary about domestic violence on people's perceptions of violence. His experiment consists of administering a brief survey to a group, having them watch a movie, then surveying them as they leave to determine if any change occurred. What kind of design is Kyo utilizing?
One group pretest-posttest
Which of the following experimental designs have the least explanatory power compared to the others? - Classical experimental design -Solomon four-group design - Posttest-only control group design - One-Shot case study
One-Shot case study
Without randomly assigning subjects, a researcher administers the experimental stimulus to the experimental group and then measures the dependent variable in both the experimental and control groups. This design is known as the:
Static-Group comparison
A friend of yours, a senior, took the Graduate Record Exam in September and scored in the 99th percentile. In February, your friend took the same exam over again. This time your friend scored in the 90th percentile. As a research methods student, you told your friend that his/her lowered score was most likely due to:
Statistical regression
The difference between the experimental and control group should be:
That the experimental group receives the independent variable and the control group does not
An instrumentation effect occurs when:
The measurement instrument is changed from pretest to the posttest
A fully representative sample is not as essential in experimental research, because we are measuring effects on the individual, not the individual themselves.
True
Experimental mortality encompasses more than just the death of participants.
True
For the most part, preexperimental designs are simplified forms of the traditional experiment.
True
In a natural experiment, the researcher does NOT manipulate the independent variable.
True
Instrumentation is NOT a threat to internal invalidity in the one-shot case study.
True
It has been suggested that within a large enough experiment and with truly randomized assignment to experimental and control groups, a pretest is unnecessary.
True
The double-blind experiment experiment attempts to guard against experimenter bias.
True
The effectiveness of randomization in experimentation is affected by the number of subjects involved.
True
The problem of external invalidity refers to the generalizability of results.
True
With a large pool of subjects, randomization is the preferred technique for assigning subjets to experimental and control groups even when you can specify in advance the relevant matching variables.
True
The experimental and control groups should be comparable on:
Variables that are likely to be related to the dependent variable under study
The question of internal invalidity refers to:
Whether the experimental stimulus really affected the dependent variable
Preexperimental designs:
are the weakest experimental designs
