Psychology scientific methods

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Psychology scientific methods

• What makes psychology a science

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• BLOND MALES ARE LESS INTELLIGENT THAN NON-BLOND
  MALES
• POOR PEOPLE ARE MORE AGGRESSIVE THAN RICH PEOPLE
• STUDENTS NAMED ULAN AND BORN IN ISSYK-KUL ARE
  UNIQUE AND ASTONISHING

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IS THIS CLAIM IS BASED ON GOOD SCIENTIFIC
RESEARCH?

• SCIENTIFIC RESEARCH is objective, systematic and
  testable
• Objective not based on personal beliefs,
  opinions and emotions
• Systematic- uses methods with which a research
  can be repeated again and again
• Testable measurable

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Who is involved in psychological research?
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Scientific research is based on SCIENTIFIC
APPROACH

• problem conceptualization
• data collection
• drawing conclusions
• revision of research conclusions and theory

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Problem conceptualization

• not vague but clear
• Not emotional development but influence of
  prenatal exposure to classic music on childrens
  ability for attachment
• not general but specific
• Not aggression, but the influence of TV on the
  teenage aggression level
• -not based on intuition
• Not education but effects of overseas experience
  of AUCA students on the level of tolerance
  towards local minority groups
• Operational definition describing all the
  aspects of a problem as precisely as possible and
  how it is to be studied in terms of observable
  events that can be measured
• Depression feeling said is not a good definition
  
• Experiencing a two weeks long or longer depressed
  characteristics such as lethargy, hopelessness
  and bad daily functioning

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Data collection

• Different research methods to collect data about
  the problem they are studying

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Research Methods

• How do psychologists study social behavior?
• Descriptive methods ? involve attempts to
  measure or record behaviors, thoughts or feelings
  in their natural state
• Experimental methods ? involve attempts to
  manipulate social processes by varying some
  aspect of the situation

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Descriptive Methods
There are 5 major types of descriptive methods.
Naturalistic Observations
Case Studies
Archives
Surveys
Psychological Tests
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Descriptive Methods
Naturalistic Observations
Involve observing behavior as it unfolds in a
natural setting

• Advantages
• behaviors are spontaneous
• dont rely on self-reports
• Disadvantages
• researcher interference
• rarity of some behaviors
• observer bias selective attention
• time consuming

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Descriptive Methods
Case Studies
Involve intensive examination of a single person
or group

• Advantages
• rich source of hypotheses
• allows studies of rare behaviors
• Disadvantages
• observer bias
• difficult to generalize
• impossible to reconstruct causes from complexity
  of past events

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Descriptive Methods
Archives
Involve gathering public records of social
behaviors

• Advantages
• easy access to large amounts of pre-recorded
  data
• little worry as to ethical issues
• Disadvantages
• many interesting social behaviors are never
  recorded
• time consuming

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Descriptive Methods
Surveys
Involve asking people questions about their
beliefs and behaviors

• Advantages
• allows study of difficult-to-observe behaviors,
  thoughts and feelings
• easy to distribute to large groups

• Disadvantages
• people who respond may not be representative
• responses may be biased or untruthful

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Descriptive Methods
Psychological Tests
Involve attempts to assess an individuals
abilities, cognitions, motivations, or behaviors

• Advantages
• allows measurement of characteristics not easily
  observeable
• Disadvantages
• tests may be unreliable
• tests may be reliable but not valid

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Descriptive Methods

• Useful for determining correlation

Correlation ? the extent to which two or more
variables are associated with one another.
If two variables are highly correlated (e.g.,
drug use and grad school applications), can we
determine the causal relationship between them?
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Correlation
Variable A could cause variable B.
Drug use could cause people to lose their jobs,
and so they end up going to grad school for
something to do.
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Correlation
Variable B could cause variable A.
The pressures of graduate school could cause
people to start drinking and using drugs.
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Correlation
Or a third variable could cause A and B.
A bad economy may drive some people to use drugs
to feel better, and others to apply to grad
school because of lack of jobs.
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LIVING TOGETHER LEADS TO DIVORCE

• Dont live together if you want to stay married.
  So says a nationwide study of over 2000 couples.
  The study found that couples who had lived
  together before getting married were 2.3 times as
  likely to get divorced as couples who had not
  lived together.
• Does living together before marriage leads to
  divorce? How else can this finding be explained?

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Possible explanations

• It is couples which are less sure about marrying
  are likely to try living together first
• Educated couples may both be more likely to test
  compatibility by living together and more likely
  to seek a divorce if the marriage is not
  satisfactory

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Experimental Methods

• In order to determine causality, we must use
  experimental methods.
• Experiment ? research method in which the
  researcher sets out to systematically manipulate
  one source of influence while holding others
  constant.

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Experimental Methods

• Independent variable (IV) ? variable manipulated
  by the experimenter
• Dependent variable (DV) ? variable measured by
  the experimenter

2 TYPES
Lab
Field
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Experimental Methods
Laboratory experiments
Involve the direct manipulation of IVs and the
observation of their effects on the behavior of
DVs.

• Advantages
• allows cause-effect conclusions
• control of extraneous variables

• Disadvantages
• artificial situations may not represent natural
  events (participants know they are being
  observed)
• lack of generalizability

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Experimental Methods
Field experiments
Involve the manipulation of IVs using unknowing
participants in natural settings.

• Advantages
• allows cause-effect conclusions
• subjects give more natural responses

• Disadvantages
• situations may still be somewhat artificial
• less control of extraneous factors

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Experimental Validity

• Internal validity ? the extent to which an
  experiment allows confident statements about
  cause and effect.
• External validity ? the extent to which the
  results of an experiment can be generalized to
  other circumstances.

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Experimental Methods

• Random assignment ? the practice of assigning
  subjects to treatments so each subject has an
  equal chance of being in any condition.
  Basketball experiment flip a coin or distribute
  cards and shuffle cards and divide into two equal
  piles.
• Confound ? A variable that systematically changes
  along with the independent variable, potentially
  leading to a mistaken conclusion about the
  independent variable.
• Demand characteristics ? cues that make subjects
  aware of how the experimenter expects them to
  behave.

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Ethical Issues in Psychological Research
www.prisonexp.org
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Video

• Discovering psychology. Disc 4. Power of
  situation. Prisoners experiment

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Ethical Issues
American Psychological Associations (APA)
ethical guidelines for research include

• Obtaining informed consent
• Informed consent ? A research subjects
  agreement to participate after being informed of
  any potential risks and his or her right to
  withdraw at any time without penalty.

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Ethical Guidelines

• 2. Fully debriefing participants after the
  research is completed.
• Debriefing ? A discussion of procedures,
  hypotheses, and subject reactions at the
  completion of the study.

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Ethical Guidelines

• 3. Evaluating the costs and benefits of the
  research procedures.
• Does the end justify the means? Are there times
  when were justified in putting participants in
  harms way?