Chapter 9

Question 1

What are the options for manipulating the independent variable?

Answer 1

How are participants going to experience the independent variable?
1. Straightforward manipulation (present material then ask what they were supposed to remember, could also do a jury decision)
vs. Staged manipulation (Used to create psychological state or simulate real world situation (uses a confederate- an actor), common in social psychology)

3. Mundane (lab representative of real lie, ) vs. experimental realism (represent emotional response, mimic feelings or emotions)

Question 2

Manipulating independent variable

Answer 2

Ensure manipulation strong enough to detect differences
ex. studying the effect of crowding-make sure they’re actually in crowded environment
* Consider the cost of the manipulation (can you afford equipment, can you afford to hire a confederate or payment to participants)
* Manipulation checks (does the independent variable induce the intended effect (checks construct validity))
ex. manipulating the effect of anxiety on memory - you would need to include a scale
* Change procedures before actual experiment
* Examine if problems are with your IV
* manipulation checks used to know what went wrong

Question 3

Measuring the Dependent Variable

Answer 3

Three types of measurements
* Self-report: questions reporting on how you think/feel/attitudes
* Behavioural: recording behaviour (look at specific time period and how often they demonstrate it) (choosing which test depends on research question)
* Physiological: recording any type of change within the body
ex. Measuring the Dependent Variabl Galvanic skin response: test for sweat (anxiety)
- Electromyogram (muscle tension)
- electrocardiogram (measuring heart rate)
- Electroencephalogram
- Functional MRI

Question 4

Issues to consider while measuring the dependent variable

Answer 4

• Sensitivity of the DV: must be sensitive enough to detect differences
  ex. likert scale more sensitive and granular than “yes or no”
• Ceiling Effects:
• task too easy everyone does well no real results or difference
• Floor Effects:
• Task is too hard, everyone does poorly, no differece or results
• Multiple dependent measures:
• Validated and reliable mesure
• Valuable but not always feasible
• depends on time $$ sometimes you just run multiple tests instead
• Order and cost considerations