Hypothesis plus
Pilot study
A small - scale trail run of a study to test any aspects of the design, with a view to making improvements
Confederate
an individual in a study who is not a real participant and has been instructed how to behave by the investigator
Alternative hypothesis
any hypothesis except the null hypothesis. It is the alternative to the null hypothesis
Directional hypothesis
states the direction of the predicted difference between two conditions or two groups of participants
Experimental hypothesis
the term used to describe the alternative hypothesis
Non-directional hypothesis
Predicts simply that there is a difference between two conditions or two groups of participants, without stating the direction of the difference
Null hypothesis
the assumption of no relationship (difference, association,etc) between variables being studied