Psychological Research Methods and Statistics

1
Psychological Research Methods and Statistics

• Chapter 2

2
2.1 What is Research?

• SAMPLE- the small group of participants, out of
  the total number available, that a researcher
  studies.
• - representative
• - nonrepresentative
• - random sample
• - stratified sample

3
Methods of Research

• Survey
• Asking many people a fixed set of questions about
  a particular subject

4
Surveys

• Types of Techniques
• Interview
• Questionnaire

5
Methods of Study (cont)

• B. Case Study
• An in-depth analysis of thoughts, feelings,
  beliefs, behaviors, etc. of a single individual
  or group.

6
Case Studies Techniques

• Types of Techniques
• Interview
• Questionnaire
• Standardized Tests
• Lab experiments (lab setting)---controlled
• Naturalistic setting---observe only

7
Methods of Study (cont)

• C. Naturalistic Observation
• The Psychologist observes the subject in a
  natural setting without interfering.

Jane Goodall
8
Methods of Study (cont)

• D. Longitudinal Studies
• data is collected about a group of participants
  over a number of years to assess how certain
  characteristics change or remain the same during
  development.

9
Methods of Study (cont)

• Cross-Sectional Study
• Data are collected from groups of participants of
  different ages and compared so that conclusions
  can be drawn about differences due to age.

10
Methods of Study (cont)

• F. Experiment
• A method for identifying cause and effect
  relationships by following a set of rules that
  minimize the possibility of error, bias or chance

11
Correlation

• An association or relationship between two or
  more events
• Correlation coefficient a number that
  indicates the strength of a relationship between
  two events

12
Correlation Coefficients

• Perfect Positive (1.00) an increase in one
  event is always matched by an increase in the 2nd
  event
• Positive (0.01 to 0.99) as one event
  increases, the 2nd event tends to, but not
  always, increase

13
Correlation Coefficients

• Negative (-0.01 to 0.99) as one event
  increases, the 2nd event tends to, but does not
  always, decrease
• Perfect Negative (-1.00) as one event
  increases, the 2nd event always decreases equally

14
Correlation vs. Causation

• Correlation does NOT show causation
• -Children that watch a lot of violent TV and
  aggressiveness.

15
Scientific Method 6 Rules of Conducting
Experiments

• Ask Research Question
• Form a Hypothesis
• Determine Variables
• Independent variable (controlled)
• Dependent variable (affected)

16
Scientific Method 6 Rules of Conducting
Experiments

• 4. Experiment
• -Experimental Group
• -Control Group
• 5. Compare Measurements
• 6. Interpret Results and Draw Conclusions.

17
(No Transcript)
18
Placebo

• Some intervention (pill, therapy, etc.) that
  resembles true medical therapy, but in fact has
  no medical effects
• Placebo effect a change in a patients illness
  due to imagined treatment effects

19
Case Studies Testimonials (cont)

• Disadvantages
• Error and bias our perception of events and
  people change when we strongly believe is
  something
• Self-fulfilling prophecy unconsciously making
  something happen due to sincere belief that it
  will