3. Characteristics
Sample size of at least 30 participants.
Outcome of the study allows the researcher to
describe whether and to what degree two ( or
more ) variables are related.
One group of subjects measured on two
variables.
4. variables must be quantifiable and usually.
represent at least ordinal scale of measure.
Variables not usually manipulated.
Cannot be used to determine causality .
A consistent relationship can be used to predict
future events.
5. Positive Correlation:
Positive correlation means that as variable A
increases, so does variable B .
High with high ,low with low
Negative Correlation:
A negative correlation is defined as when
variable A increases, variable B will decrease.
High with low , low with high
6. Correlation coefficient
A correlation coefficient, defined as a
numerical representation of the strength and
direction of a relationship.
The correlation coefficient of -1 indicates a
weak/negative relationship.
A +1 indicates a strong/positive relationship
while a 0 indicates no relationship at all.
7. Steps
1. Selecting a problem
2. Choosing a sample (n=30 at least)
3. Selecting or developing instruments (tests,
questionnaires, observation)
4. Collecting and analyzing data
5. Interpreting results
8. Examples
The relationship between high I.Q and high
GPA.
The relationship between low economical
conditions and domestic violence .
The relationship between unemployment and
increasing rate of suicide.
9. The Relationship between profitability of
company and salary increase of employees.
Relationship between Stock exchange and
Political situation of country.
10. Types of Correlational Research
• There are three common types of
correlational research.
1) Natural observation
2) Survey research
3) Archival research
11. Natural observation
Natural observation is observing and recording
variables in a natural environment, without
interfering.
it can be time consuming and does not allow
variable control.
12. • Survey Research
Survey research gathers information via
surveys or questionnaires by choosing
a random sample of participants.
Survey research is quick and convenient, but
participants can affect the outcomes in a
variety of ways.
13. Archival Research
Archival research analyzes data collected
by others.
Archive research is often free. However,
large amounts of data are needed in order
to see any type of significant relationship.
Researchers cannot control the data or
how it was gathered.
