PSY 310 Chapter 5
Types of order effects
(1) Practice effects (2) Fatigue effects (3) Carryover effects (4) Sensitization effects
Randomized clinical trial
A controlled medical experiment in which subjects are randomly chosen to receive either an experimental treatment or a standard treatment (or placebo).
Which of the following best describes external validity? A) The extent to which the results of an experiment can be generalized to other populations and settings B) The proper statistical treatment of data and the soundness of statistical conclusions C) The quality of the experiment's manipulations and the clarity of the operational definitions D) The ability of an experiment to control extraneous variables and isolate the effect of the independent variable
A) The extent to which the results of an experiment can be generalized to other populations and settings
What is a carryover effect in within-subjects experiments? A. An effect of being tested in one condition on participants' behavior in later conditions. B. An effect of the independent variable on the dependent variable. C. An effect of the order of conditions on the dependent variable. D. An effect of extraneous variables on the dependent variable.
A. An effect of being tested in one condition on participants' behavior in later conditions.
What is a confounding variable? A. An extraneous variable that varies systematically with the independent variable B. An extraneous variable that is irrelevant to the study C. An independent variable that is difficult to manipulate D. A dependent variable that is influenced by multiple factors
A. An extraneous variable that varies systematically with the independent variable
Carryover effect
An effect of being tested in one condition on participants' behavior in later conditions.
Fatigue effect
An effect where participants perform a task worse in later conditions because they become tired or bored.
Single Factor Two-Level Design
An experiment design involving a single independent variable with two conditions.
Construct validity is concerned with: A) The proper statistical treatment of data and the soundness of statistical conclusions B) The ability of an experiment to measure the intended construct C) The extent to which the results of an experiment can be generalized to other populations and settings D) The clarity of the operational definitions and the quality of the experiment's manipulations
B) The ability of an experiment to measure the intended construct
Statistical validity is threatened when: A) The experiment lacks control over extraneous variables B) The statistical analysis is not appropriate for the data and design of the study C) The experiment does not measure the intended construct D) The results of the experiment cannot be generalized to other populations and settings
B) The statistical analysis is not appropriate for the data and design of the study
How does counterbalancing help to address carryover effects? A. By ensuring that participants are matched on relevant variables before the experiment. B. By randomizing the order of conditions for each participant. C. By using statistical techniques to control for extraneous variables. D. By using a Latin square design to assign participants to different orders.
B. By randomizing the order of conditions for each participant.
Which of the following is a key feature of an experiment? A. Observing natural behavior without interference B. Manipulating the independent variable C. Using survey methods to collect data D. Analyzing existing data sets
B. Manipulating the independent variable
How does random assignment differ from random sampling? A. Random assignment is used to select a sample from a population, while random sampling is used to assign participants to different conditions. B. Random assignment is used to assign participants to different conditions, while random sampling is used to select a sample from a population. C. Random assignment is used in observational studies, while random sampling is used in experimental studies. D. Random assignment and random sampling are two terms for the same procedure.
B. Random assignment is used to assign participants to different conditions, while random sampling is used to select a sample from a population.
What is the purpose of a control condition in an experiment? A. To ensure that participants are treated ethically B. To provide a baseline for comparison with the treatment condition C. To manipulate the independent variable D. To control extraneous variables
B. To provide a baseline for comparison with the treatment condition
How do researchers prioritize the four big validities (internal, external, construct, and statistical) in designing an experiment? A) By focusing primarily on internal validity and sacrificing the others B) By prioritizing external validity over the others C) By balancing and considering trade-offs among the four validities D) By prioritizing statistical validity over the others
C) By balancing and considering trade-offs among the four validities
What does internal validity refer to in an experiment? A) The ability to generalize the results to other populations B) The soundness of the researchers' statistical conclusions C) The extent to which the experimental design supports causal conclusions D) The ability of the experiment to measure the intended construct
C) The extent to which the experimental design supports causal conclusions
How do researchers control extraneous variables in an experiment? A. By manipulating the dependent variable B. By randomizing participants C. By holding them constant D. By using statistical techniques after data collection
C. By holding them constant
What is the primary difference between between-subjects and within-subjects experiments? A. The number of participants B. The number of conditions C. The way participants experience the independent variable D. The statistical procedures used for analysis
C. The way participants experience the independent variable
What is the primary goal of an experiment? A. To describe a phenomenon B. To predict future outcomes C. To establish causal relationships D. To explore relationships between variables
C. To establish causal relationships
When is it generally preferable to use a within-subjects design over a between-subjects design? A. When the study involves long-term changes in behavior. B. When carryover effects are a major concern. C. When it is feasible to test each participant in all conditions. D. When the study involves a large number of extraneous variables.
C. When it is feasible to test each participant in all conditions.
wait-list control condition
Condition in which participants are told that they will receive the treatment but must wait until the participants in the treatment condition have already received it.
True or False: Random assignment to conditions in between-subjects experiments or counterbalancing of orders of conditions in within-subjects experiments is NOT a fundamental element of experimental research.
False ( the purpose is to control extraneous variables so that they do not become confounding variables)
High Internal validity
This can lead to low external validity. However, showcases that the independent variable causes any observed differences in the dependent variables.
High External validity
This can lead to low internal validity. However, this means that the results can be generalized to people and situations beyond those actually studied.
True or False: An experiment is a type of empirical study that features the manipulation of an independent variable, the measurement of a dependent variable, and control of extraneous variables.
True
Context effect (or contrast effect)
Unintended influences on respondents' answers because they are not related to the content of the item but to the context in which the item appears.
Single factor multi level design
When an experiment has one independent variable that is manipulated to produce more than two conditions
What does experimental research on the effectiveness of a treatment require?
a treatment condition and a control condition (can be a no-treatment control, a placebo condition, or a wait-list control condition)
Practice effects
an effect where participants perform a task better in later conditions because they have had chance to practice it.
between-subjects experiment
an experiment in which each participant is tested in only one condition (ex: a researcher with a sample of 100 university students might assign half of them to write about a traumatic event and the other half write about a neutral event.)
matched-groups design
an experimental design in which participants who are similar on some measured variable are grouped into sets and the members of each matched set are then randomly assigned to different experimental conditions
What is a confound?
an extraneous variable that varies systematically with the independent variable.
What is an extraneous variable?
any variable other than the independent and dependent variables.
Effective recruiting methods for research
formal subject pools advertisements personal appeals
Why is it important to standardize experimental procedures?
to minimize extraneous variables, including experimenters expectancy effects
within-subjects experiment
research design in which each subject experiences every condition of the experiment (primary advantage is that it provides maximum control of extraneous participant variables)
disadvantages of within-subjects designs
they can result in order effects (an effect that occurs when participants' responses in the various conditions are affected by the order of conditions to which they were exposed)
Why is it important to conduct one or more small-scale pilot tests of an experiment
to be sure that the procedure works as planned