Descriptive research

1
Descriptive research

• Usually correlational
• THIS IS NOT CAUSE AND EFFECT!
• Cannot establish which came first.
• Cannot control other variables

2
Why bother?

• Source of information for experimental studies.
• Describes behavior.
• Can help to predict behavior.

3
Goals of Descriptive Methods

• Objectively measure variables
• Operational definitions
• Provides a tracking mechanism.
• Consistent measures offer objective data.
• Determines degree of relationship.
• Objective value is produced (illusory r)
• Summarizes large amount of data

4
Ex post facto research

• After the fact research
• External validity is hindered by lack of random
  selection.
• Construct validity is hindered by
  instrumentation.
• Internal validity is simply not possible

5
Archival research

• Data someone else has collected
• Coding
• Content analysis - coding of free response must
  train raters.
• Lacks internal validity
• Construct validity
• Instrumentation bias
• External validity is good because of large sample
  size

6
Observational Research

• Naturalistic observation - external
• Participant observation - internal
• Problems
• Participants may react to being observed
• Observers may be biased in recording
• Solutions
• Be unobtrusive
• Be less noticeable, blend in.

7
Tests

• Administration of multiple instruments
• External validity is dependent on the sample
• Internal validity is correlational ONLY

8
Correlation

• Ranges from 1.00 to 1.00
• Higher value indicates a stronger relationship.
  Scatterplot.
• Can be positive or negative
• Percentage of accounted variance is r2 also
  called a coefficient of determination