Aims, hypothesis, and variables

Question 1

What is an aim?

Answer 1

A general statement of what the researcher is investigating in an experiment
e.g.:
- to investigate the impact of anxiety on eye witness testimony

Question 1

What is an independent variable?

Answer 1

Factor in experiment being manipulated by researcher to see what influence it has on the dependent variable. (Can also be something that changes naturally)
e.g. level of anxiety

Question 2

What is a dependent variable?

Answer 2

Variable that is measured in the experiment. Affected by change in the independent variable.
e.g. accuracy of eyewitness testimony (recognition rate of perpetrator)

Question 3

What is an extraneous variable?

Answer 3

Any other variable apart from the independent variable that affects the dependent variable. Affects both conditions being tested and are usually participant variables.
e.g. energy levels, age, ability in what is being tested

Question 4

What is a confounding variable?

Answer 4

• Type of extraneous variable
• Affects only one condition - usually situational
• May occur due to lack of standardised procedure
• e.g. background noise in one condition

Question 5

What is a hypothesis?

Answer 5

A testable statement about the outcome of a study
e.g. there will be a significant increase/decrease in the DV when in IV1 compared to IV2

Question 6

What is operationalisation?

Answer 6

• Clearly defining variables so that they can be measured numerically and specifically
• Do this to: increase objectivity and decrease researcher bias, increase repeatability leading to reliability and consistency

Question 7

What is the difference between a null and alternate hypothesis?

Answer 7

A null hypothesis predicts that there will be no significant effect on DV whereas an alternate hypothesis predicts that there will be an effect.

Alternate is more common - use this as default in exam unless asked to write a null hypothesis specifically

Question 8

What is the difference between a directional and non-directional hypothesis?

Answer 8

• A directional hypothesis indicates the direction of change as it is certain of the direction of change whereas a non-directional hypothesis doesn’t indicate direction as it isn’t certain of the direction of change
• Directional is usually used when there IS previous research on the topic of study
• e.g. directional = significant increase/decrease, non-directional = significant effect

Question 9

What is a pilot study and why are they used?

Answer 9

• A small scale trial run of the main study using small groups of PPs taken from the TP
• Pilot studies help improve the quality of research and save unecessary work time and money
• e.g. test that the questions are clear and that appropriate language is used to set timings of tasks
• Help tests methodology and ensure its effective e.g. PPs have enough time to do tests