Lesson 1: Experimental Methods

Question 1

What is the independent variable?

Answer 1

The variable that the researcher manipulates in order to determine its effect on the dependent variable. The independent variable may be divided into levels, sometimes referred to as experimental conditions.

Question 2

What is a control condition?

Answer 2

To provide a standard against which experimental conditions can be compared. There may be a control condition where the IV is not manipulated at all

Question 3

What is the dependent variable?

Answer 3

The variable that is being measured.

Question 4

What are Extraneous variables?

Answer 4

There are any variables other than the IV that could affect the DV

Question 5

What are confounding variables?

Answer 5

There are any variables that have affected the DV

Question 6

What are Lab experiments?

Answer 6

• Controlled environment
• Eliminate EV
• Artificial Setting

Question 7

Advantages of lab experiments

Answer 7

1. High control over the IV and conditions, prevents EV.
2. Researcher can determine cause and effect between IV and DV
3. Reliable, replication is easy

Question 8

Disadvantages of lab experiments

Answer 8

1. Demand Characteristics, Possible social desirability bias
2. lacks mundane realism and ecological validity

Question 9

What are field experiments?

Answer 9

• Experiment carried out in the real world/natural setting

- IV is still manipulated

Question 10

Advantages of field experiments

Answer 10

1. More Mundane realism and ecological validity than labs. Reflects real life
2. Researcher can determine cause and effect between IV and DV
3. Less chance of demand characteristics, more natural behaviour and therefore more valid results

Question 11

Disadvantages of field experiments

Answer 11

1. Less control over EV, not valid
2. Less sample control, not representative
3. Difficult to repeat, unreliable

Question 12

What is a natural experiment?

Answer 12

• The researcher takes advantage of a naturally occurring IV to see its effect on the DV
• Measures variables that aren’t directly manipulated

Question 13

Advantages of natural experiments

Answer 13

1. High mundane realism and ecological validity

2. Useful when it is unethical or impossible to manipulate the IV in a lab.

Question 14

Disadvantages of natural experiments

Answer 14

1. Low control over EV
2. Difficult to repeat, unreliable
3. Difficult to determine cause and effect

Question 15

What is a Quasi Experiment?

Answer 15

• Contain a naturally occurring IV with a difference that already exists e.g gender, age.
• Researcher examines the effect on DV
• Usually occur in labs

Question 16

Advantages of Quasi Experiments

Answer 16

1. High control, EV effects are minimised

2. Replication is likely

Question 17

Disadvantages of Quasi Experiments

Answer 17

1. Lacks ecological validity

2. Demand characteristics may occur, invalid results