Aims and Hypotheses

What is an aim in psychological research?

An aim is a general statement of what the researcher intends to investigate.

• It identifies the purpose of the study, often focusing on the relationship between two variables.

What is a hypothesis?

A hypothesis is a testable statement that predicts a relationship or difference between variables in a study.

What is a non-directional hypothesis?

A non-directional hypothesis predicts that there will be a difference or relationship, but does not specify the direction of the effect.

E.g. “There will be a difference in memory recall between participants who sleep more and those who sleep less”

What is a directional hypothesis?

A directional hypothesis states that there is a difference in the measurement of the dependant variable (as a result of the manipulation of the IV) and says which direction the results will go.

E.g. “Participants who sleep more will recall higher number of words than those who sleep less.”

When should you use a directional vs non-directional hypothesis?

• Use a directional hypothesis when previous research suggests the direction of the effect.

• Use a non-directional hypothesis when there’s little or no previous research, or when findings are mixed/inconclusive.

What is a null hypothesis?

The null hypothesis states that there is no change or difference in the measurement of the DV as a result of the manipulation in the IV

What is an alternative hypothesis?

An alternative hypothesis is a testable statement that predicts there will be a difference or a change in the measurement of the DV as a result of the manipulation in the IV