Artifacts
: threats to internal AND external validity (p.
An artifact is an external factor that can influence or distort measurement. Your textbook describes three types of artifacts: experimenter bias, demand characteristics and participant reactivity, and exaggerated variables.
Which of the following is an external factor that may influence or distort the measurements in a research study?
Artifacts
: threats to internal AND external validity (p.
An artifact is an external factor that can influence or distort measurement. Your textbook describes three types of artifacts: experimenter bias, demand characteristics and participant reactivity, and exaggerated variables.
What term refers to a variable that Cannot be observed or measured directly but is useful for?
Operational
definition. A procedure for indirectly measuring and defining a variable that cannot be observed or measured directly.
What is threats to external validity?
The external validity of a study is the extent to which you can generalize your findings to different groups of people, situations, and measures. … There are seven threats to external validity:
selection bias, history, experimenter effect, Hawthorne effect, testing effect, aptitude-treatment and situation effect
.
Which effects occur when environmental events other than the treatment influence the participants scores in one treatment differently than in another treatment?
A history effect
is an outside, environmental variable that influences the participants' scores in one treatment condition differently than in other conditions. An extraneous variable is any variable that is part of a research study but not directly investigated.
What is the difference between internal and external observation?
Internal and external
validity
are concepts that reflect whether or not the results of a study are trustworthy and meaningful. While internal validity relates to how well a study is conducted (its structure), external validity relates to how applicable the findings are to the real world.
What is the statement of the predicted relationship between two or more variable in a research study?
A hypothesis
states a presumed relationship between two variables in a way that can be tested with empirical data. It may take the form of a cause-effect statement, or an “if x,…then y” statement. The cause is called the independent variable; and the effect is called the dependent variable.
What is the difference between a construct and a variable?
Constructs are conceptualized at the theoretical (abstract) plane, while variables are operationalized and measured at the empirical (observational) plane. Thinking like a researcher implies the ability to move back and forth between these two planes.
What is a measured variable?
A measurement variable is
an unknown attribute that measures a particular entity and can take one or more values
. It is commonly used for scientific research purposes. Unlike in mathematics, measurement variables can not only take quantitative values but can also take qualitative values in statistics.
What is an operational variable?
Operational variables (or operationalizing definitions)
refer to how you will define and measure a specific variable as it is used in your study
. … Operationalization has the great advantage that it generally provides a clear and objective definition of even complex variables.
What is an example of external validity?
External validity is another name for the generalizability of results, asking “whether a causal relationship holds over variation in persons, settings, treatments and outcomes.”
1
A classic example of an external validity concern is
whether traditional economics or psychology lab experiments carried out on college
…
What are the limits to generalizability in terms of external validity?
“A threat to external validity is an explanation of how you might be wrong in making a generalization from the findings of a particular study.” In most cases, generalizability is
limited when the effect of one factor (i.e. the independent variable) depends on other factors
.
What factors affect external validity?
- Population characteristics (subjects)
- Interaction of subject selection and research.
- Descriptive explicitness of the independent variable.
- The effect of the research environment.
- Researcher or experimenter effects.
- Data collection methodology.
- The effect of time.
How many groups of participants would be needed to completely counterbalance?
For even four treatment conditions,
24 groups
would be needed for a completely counterbalanced design. Obviously, this would be impractical because too many participants would be needed to do such an experiment.
Why is random assignment used in between-subjects experimental designs quizlet?
Randomly select the participants from the population. In a between-subjects experiment, participants are assigned to treatments using random assignment. Why is random assignment used?
It is an attempt to control participant variables so they don't become confounding variables
.
Which of the following is the primary goal for randomizing an extraneous variable in an experiment?
Which of the following is the primary goal for randomizing an extraneous variable in an experiment?
Minimize the likelihood that the variable is confounding
. … For an experiment comparing two treatments, the researcher selects participants so that each treatment condition has 20 males and 10 females.
