KA 2: experimentation: experimental design: independent and dependent variables Flashcards
what is the independent variable?
the variable that is changed in a scientific experiment
what is the dependent variable?
the variable being measured in a scientific experiment
independent and dependent variables can be…
continuous or discrete
what do experiments involve?
the manipulation of the independent variable by the investigator
what is the experimental treatment group compared to?
a control group
what is a simple experimental design?
one independent variable
what is a multifactorial experimental design?
more than one independent variable
what does the control laboratory conditions allow?
simple experiments to be conducted more easily than in the field
what is a drawback of a simple experiment?
that its findings may not be applicable to a wider setting
what does a multifactorial experiment involve?
a multifactorial a combination of more than one independent variable or combination of treatments
why is there no truly independent variable?
as investigators may use groups that already exist
what is an observational study?
the independent variable is not directly controlled by the investigator, for ethical or logistical reasons
what is the pro and con of observational studies
- good at detecting correlation
- since they do not directly test a hypothesis, they are less useful for determining causation
