variables
This variable is the presumed cause
Independent variable
What is the fur color of all the housecats in the Picadome neighborhood of Lexington, KY?
descriptive
The following statement is what type of hypothesis?
"Getting drunk before the test will be associated with a higher error rate compared with the error rate for students who do not get drunk before the test."
directional
This type of variable is directly manipulated by the investigator.
Independent variable.
What is the relationship between self-reported lack of sleep and midterm grades in OS students?
exploratory
What type of hypothesis is illustrated here:
"There will be no difference in grades for students who forget to study for the test versus students who study for 10,0000 hours."
null
This type of unwanted variable is not directly manipulated by the investigator and yet still may influence the dependent variable.
Intervening variable (also called "nuisance" or "confounding" variable).
What is the astrological sign of each woman in this class?
descriptive
Students who did not study for the test will achieve a different grade compared with students who did.
alternative hypothesis
(note: the researcher did not indicate a direction of the effect).
This variable is the effect that gets measured.
Dependent variable
What is the relationship between astrological sign and midterm grades in the OS program?
exploratory
There will be an increase in happiness associated with fall break.
directional
This is a concrete representation of an abstraction, the value of which may vary.
variable
What effect will daily massage have on the healing rate of gastrocnemius muscle tears in female college gymnasts ages 18-22?
There will be a change in mood associated with fall break.
non-directional