Basics Overview

Question 1

Different Types of Research Design

Answer 1

There are two basic types of design.
The design you use depends upon your research question.

Are you looking for a relationship between or amongst variables?
 relational design
Are you looking for a difference between groups or conditions?
 experimental design
( quasi-experimental)

Question 2

Relational Design Examples

Answer 2

Is there a relationship between height and age in children?
This is an example of CORRELATION.

Is there a relationship between height and age in children?
This is an example of CORRELATION
Does age predict height in children?
This is an example of REGRESSION.

Question 3

Experimental Designs 1

Answer 3

BETWEEN-SUBJECTS design:

Differences between groups
Different people in each group
Each person takes part in only one condition and contribute only one score
aka Independent Groups design

Question 4

Example of Between Subjects Design

Answer 4

Are older adults’ reaction times longer than younger adults?
Is there a difference between older and younger age groups in reaction times?
Quasi-experimental: random allocation to groups isn’t possible
Big issue is that participants may vary in other ways than the IV: individual differences

Question 5

Experimental Designs 2

Answer 5

WITHIN-PARTICIPANTS / WITHIN-SUBJECTS design

Differences between conditions
The same people in each condition
Each person takes part all conditions and contributes a score in each condition
Issues with order effects, but easily controlled by counterbalancing
Controls for individual differences: each participant is their own control

Question 6

Example of Within Subjects Design

Answer 6

Are Alpha wave amplitudes in individuals greater with eyes open or eyes closed?
Is there a difference in alpha amplitudes when people’s eyes are open or closed?
This is a within-subjects design

Question 7

Different Types of Variables

Answer 7

Independent Variables (IV)
They can be changed/manipulated by the experimenter (e.g. learning methods, dual or single tasks, congruent or incongruent conditions)

Dependent Variables (DV)
They will be affected by the manipulation (changed by the influence of the manipulated independent variable (e.g. exam results, response accuracy, reaction times))

Question 8

Confounding Variables

Answer 8

The IV is manipulated (cause).

The DV is measured (effect).

Confounding variable: anything that could influence your outcome/DV (e.g. time of day, noise level, previous knowledge) that isn’t your independent variable

Question 9

Levels of Measurement

Answer 9

There are four basic ones (NOIR)
NOMINAL
ORDINAL
INTERVAL
RATIO

Question 10

Nominal Data

Answer 10

Not numerically related
Categories/categorial
Mutually exclusive
Remember: Nominal = name

Question 11

Ordinal Data

Answer 11

Not numerically related
Ranked or placed in order
Differences between scores don’t represent REAL differences. 
They are discrete.
Remember: ordinal = order

Question 12

Interval Data

Answer 12

Numerically related
Order
Differences between individual scores are equal
Don’t have a ‘true zero’ (can be negative, e.g. temperature in celcius, difference in reaction times between two conditions)
They can be discrete (whole numbers) or continuous (with decimal places).
Remember: interval = space in between

Question 13

Ratio

Answer 13

Numerically related
Order
Equal differences between values
Absolute zero, scores cannot be negative
They can be discrete or continuous.