Aims, hypothesis, IVs & DVs

Aims: What is a research aim?

A clear statement of what the researcher intends to investigate.

E.g; To examine the effect of hunger on memory.

How should an experiment aim usually begin when writing it?

“To examine the effect of..”

What’s the difference between a research question and aim?

A research q asks what’s being investigated, while an aim states what the study tends to examine.

IV & DVs: Whats IV and DV?

• IV - The v the researcher manipulates to observe its effect.

• DV - The v being measured, which is affected by the IV.

How can u identify the IV and DV in a study?

• IV - it’s the v being deliberately changed by researcher.

• DV - the outcome that’s measured.

What does the presence of an IV and DV indicate?

The study is experimental.

(If no IV DV = non-experimental)

Hypotheses: What is a hypothesis?

A clear, precise, and testable prediction about the rship or difference between v’s.

What is operationalisation?

Clearly defining how variables are measured or manipulated.

Why must variables be operationalised?

To ensure they are measurable and specific.

What should an experimental hypothesis always include?

An operationalised IV and DV.

What are the 2 types of hypothesis?

• Directional hypothesis

• Non-directional hypothesis

Whats a directional hypothesis?

• A hypothesis that predicts the specific direction of the effect.

• Another name= one-tailed.

When is a directional hypothesis used?

• When previous research suggests the likely direction of the result.

• Key words - higher, lower, more, less, increase, decrease, +ve, -ve.

Whats an example of a directional hypothesis?

Hungry participants will recall more food-related words than non-hungry participants.

Non-directional hypothesis: What is a non-directional hypothesis?

• A hypothesis predicting a difference but not the direction.

• Other name = Two-tailed hypothesis

When is a non-directional hypothesis used?

• When previous research is inconclusive.

• Key words - ‘Difference’

Whats an example of a non-directional hypothesis?

There will be a difference in recall of food-related words between hungry and non-hungry participants.

Null hypothesis: What is a null hypotheis?

A prediction that there will be no significant difference or rship.

What does the null hypothesis assume about any observed difference?

That it’s due to chance.

Example of a null hypothesis?

There will be no significant difference in recall of food-related words between hungry and non-hungry participants; any difference will be due to chance.

Exam Tip: Whats the biggest mistake made in exams when writing hypothesis?

Failing to operationalise IV and DV.