Measurements
Name the three methods of measuring a variable.
Self-Report
Observational (Behavioral)
Physiological
Term for a variable that is manipulated in an experiment
Independent
What are the (4) scales of measurement, and which are quantitative?
Nominal (Categorical)
Ordinal
Interval
Ratio
Here's an example of it: “The average American spends 3 hours per day on social media.”
Frequency claim
This is a priority for all three study claims (Frequency, Association, Causal)
Construct
A measurement in which people answer questions about themselves in a questionnaire or interview.
Self-report
Type of variable measured to determine the outcome of an experiment
Dependent
A variable whose levels are categories (example: brown, blue, and green are each levels for the variable eye color).
Nominal Variable (Categorical Variable)
“People who exercise more report greater life satisfaction.” This statement exemplifies this type of claim.
Association
Effect size, a measure of the magnitude of the experimental effect is important to this validity.
Statistical
Measuring a variable by recording observable behaviors
Observational/Behavioral
In a study examining the impact of sleep on memory performance, what is the independent variable?
Sleep
A quantitative measurement scale whose levels represent ranked order, and distances between levels are not equal (example: finishing first, second, or third in a race).
What is an ordinal scale?
Covariance, temporal precedence, and internal validity are its criteria.
Causality
A study has a r=0.1 but the conclusion states that there is a strong correlation. Which validity is threatened?
Statistical
A method of measuring a variable by recording biological data.
Physiological
In an experiment testing the effect of caffeine on reaction time, what is the dependent variable?
Reaction time
A quantitative measurement scale that has no “true zero,” and in which the numerals represent equal intervals (distances) between levels (example: temperature in degrees).
Interval Scale
The use of cell phones while driving causes more traffic accidents.” This statement is an example of it.
Causal claim
Does measuring a participants heartbeat to indicate stress have strong construct Validity?
A heartbeat can increase for multiple reason that are not related to stress. This would be a poor operational definition for stress and therefore this study would have weak Construct Validity.
Measuring a person's heartbeat is an example of a(n) ______ measurement.
Physiological
Term for a variable that could influence the dependent variable, but is not the focus of a study
Third/confound/extraneous
A researcher measures participants' height in centimeters. What type of measurement scale is this?
Ratio
Participants trained in meditation showed lower stress than those who were not trained. This is not a causal claim because...
Random assignment not mentioned/Internal validity is unclear
What is the validity of a claim?
The degree to which empirical evidence and theoretical rationales support the adequacy and appropriateness of conclusions/claims.