The Need for Psychological Science

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The Need for Psychological Science
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Scientific Method

• To produce knowledge (pure research) or solve
  practical problems (applied research)
• ? Theory explains, organizes and enables one to
  predict behavior or events
• ? Hypotheses a statement to test and revise
  theories a measurable relationship/prediction
  between variables (beer parties GPA)
• ? Replicate repeat studies independently to
  extend validity and reliability of research

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The Need for Psychological ScienceExamples of
Faulty Reasoning

• Hindsight Bias I-knew-it-all-along phenomenon
• The mind builds its current wisdom around what we
  have already been told. We are biased in favor
  of old information.
• For example, we may stay in a bad relationship
  because it has lasted this far and thus was
  meant to be.

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Hindsight Bias Examples

• A letter comes in the mail informing an
  individual that he was accepted into a college.
  When he tells his mother she says, I really had
  a feeling that you were going to get in (even
  though she had expressed doubts to his father
  earlier that week).
• An individual notices that outside, its
  beginning to look a little bit gray. He says to
  himself, I bet that its going to rain this
  afternoon. When it actually does rain, the
  individual tells himself that he was certain that
  it would when he saw the clouds rolling in earlier

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Overconfidence The tendency to think we know
more than we do

• We are much too certain in our judgments.
• We overestimate our performance, our rate of
  work, our skills, and our degree of self-control.

• We overestimate the accuracy of our knowledge.
  People are much more certain than they are
  accurate.
• Overconfidence is a problem in eyewitness
  testimony.
• Overconfidence is also a problem on tests. If
  you feel confident that you know a concept, try
  explaining it to someone else.

• Overconfidence Error 1Performance

• Overconfidence Error 2Accuracy

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Overconfidence continued

• The 'God Complex', we tend to believe that we
  know the answer to complicated problems. This can
  be seen in daily gossip where individuals
  confidently propose solutions to world issues.
• Ex. Teachers sometimes decide that some
  individuals and groups are more intelligent than
  others.

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• Scientific Attitude driven by curiosity and
  critical thinking examining assumptions,
  uncovering hidden values, evaluate evidence and
  assessing conclusions (TWA and 60 Minutes).
• http//www.cbsnews.com/8301-505263_162-57590192/tw
  a-flight-800-crash-inside-the-missile-theory/

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• Confirmation bias A tendency to search for
  information that confirms ones preconceptions
• decision makers have been shown to actively seek
  out and assign more weight to evidence that
  confirms their hypothesis, and ignore or
  underweigh evidence that could disconfirm their
  hypothesis.
• False consensus effect The tendency to
  overestimate the extent to which others share our
  beliefs, behaviors, and attitudes.
• Ex Romantic relationships between people often
  start off with a glow as hormones and False
  Consensus overshadow real differences. However,
  the cloud-9 effect eventually wears off as the
  loving couple eventually discover that they are
  not, after all, that similar (and in fact often
  are amazingly incompatible!).

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• Belief bias - The tendency for ones preexisting
  beliefs to distort logical reasoning.
• Ex I will accept that some good ice skaters are
  not professional hockey players, but will reject
  an assertion that some professional hockey
  players are not good ice skaters (which, although
  it seems unlikely, is possible).
• Belief perseverance - The tendency to cling to
  ones conceptions after the basis on which they
  were formed are discredited.
• Zombie Apocalypse??

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Scientific Attitude Part 1 Curiosity

• always asking new questions
• That behavior Im noticing in that guy is that
  common to all people? Or is it more common when
  under stress? Or only common for males?
• Hypothesis Curiosity, if not guided by caution,
  can lead to the death of felines and perhaps
  humans.

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Scientific Attitude Part 2 Skepticism

• not accepting a fact as true without
  challenging it seeing if facts can withstand
  attempts to disprove them.
• Skepticism, like curiosity, generates questions
  Is there another explanation for the behavior I
  am seeing? Is there a problem with how I
  measured it, or how I set up my experiment? Do I
  need to change my theory to fit the evidence?

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Scientific Attitude Part 3 Humility

• Humility refers to seeking the truth rather than
  trying to be right a scientist needs to be able
  to accept being wrong.
• What matters is not my opinion or yours, but
  the truth nature reveals in response to our
  questioning. David Myers

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Research Methods in Psychology

• Descriptive Methods
• Naturalistic Observation
• gathering data about behavior watching but not
  intervening
• Case Studies
• observing and gathering information to compile an
  in-depth study of one individual
• Surveys and Interviews
• having other people report on their own attitudes
  and behavior

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Case Studies

• Examining one individual in depth
• Benefit can be a source of ideas about human
  nature in general
• Example cases of brain damage have suggested
  the function of different parts of the
  brain (e.g. Phineas Gage)
• Danger overgeneralization from one example he
  got better after tapping his head so tapping must
  be the key to health!
• http//www.youtube.com/watch?v9QXI_BxlY7M

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Natural Observation

• Observing natural behavior means just watching
  (and taking notes), and not trying to change
  anything.
• This method can be used to study more than one
  individual, and to find truths that apply to a
  broader population.

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Survey

• A method of gathering information about many
  peoples thoughts or behaviors through
  self-report rather than observation.
• Keys to getting useful information
• Be careful about the wording of questions
• Only question randomly sampled people

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• Correlational research (May include survey,
  interviews, tests, naturalistic observation,
  longitudinal, cross-sectional studies)
• Experimental
• Quasi-Experimental (no random assignment to
  condition)

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Research Methods in Psychology
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Descriptive Research Methods

• Naturalistic observation
• Advantages
• Avoids observer effect/reactivity (of subject)
• Provides ideas for further research
• Disadvantages
• Potentially time consuming and expensive
• No control of variables or over extraneous
  variables
• Not replicable
• Examples Piaget, Naturalistic examples, Quasi

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Descriptive Research Methods

• Surveys, interviews, questionnaires and tests
• Advantages
• Relatively inexpensive, easy way of collecting
  large amounts of data (attitudes, interests,
  aptitudes)
• Assuming a true random sample generalizable
• Disadvantages
• Poor construction or administration of questions
• Poor sample unrepresentative (not generalizable)
• Measures beliefs, not behaviors
• Issues of self-report, memory and honesty

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Descriptive Research Methods

• Case studies Of individuals, groups or
  phenomena
• Advantages
• Potentially, deeply revealing about individuals
• Disadvantages
• No experimental control
• Sample size extremely small generalizability?
• Potential bias, both subject and experimenter
• Examples, Phineas Gage, Freud and Little Hans

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Descriptive Research Methods

• Archival Research
• Advantages
• Enormous amounts of data used to see trends
  relationships and outcomes
• Disadvantages
• No control over data collection or if reliable
• Examples Analysis of studies conducted by other
  researchers, or look at historical data (e.g. the
  Wild Child)

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Research Methods

• Longitudinal method Examples? Ads/Disads?
• Cross-sectional method Advantages?
• Cross-cultural method Purposes?

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Correlational Studies

• Correlational studies look at the degree of
  relationship between variables and not the effect
  of one variable on another variable
• Correlation DOES NOT equal causation. A
  relationship may be suggested, but it does not
  prove that one variable causes the other to
  change. For example, a correlational study may
  suggest a relationship between academic success
  an self-esteem, but it does not mean that
  academic success causes increases self-esteem

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Finding Correlations Scatterplots

• Place a dot on the graph for each person,
  corresponding to the numbers for their height and
  shoe size.
• In this imaginary example, height correlates with
  shoe size as height goes up, shoe size goes up.

Height
Shoe size
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Correlational Studies
Partic GPA TV Hours/ week
1 3.1 14
2 2.4 10
3 2.0 20
4 3.8 7
5 2.2 25
6 3.4 9
7 2.9 15
8 3.2 13
9 3.7 4
10 3.5 21
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Correlational Studies

• Examples of Positive Correlation
• 1. SAT scores and college those with higher SAT
  scores also have higher grades in college
• 2. Happiness and helpfulness as peoples
  happiness level increases, so does their
  helpfulness
• Examples of Negative Correlation
• 1. Education and years in jail people who have
  more years of education tend to have fewer years
  in jail
• 2. Crying and being held babies held less tend to
  cry more

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Scatterplots and Correlation

• Correlation coefficient (Pearson-product moment
  correlation coefficent) measures 3 types
• 1.00 Positive (or direct)
• -1.00 Negative (indirect)
• 0 No correlation

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Correlational Studies - Problems

• Illusory correlation detecting relationships
  where none exist (weathercold). Other examples?
• Third-Variable
• Research showed a strong correlation between
  contraceptive use and number of electrical
  appliances in the home (Li, 1975).   Why?  
• CorrelationMethodsReviewWS

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Experimentation

• Important Terms/Concepts. Most knowmust know
• hypothesis
• independent/dependent variables
• operational definitions (quantifiable)
• population and random/stratified sample
• representative sample
• generalizability
• experimental and control group (or condition)
• random assignment
• placebo use and effect
• confounding variables
• single and double blind procedures
• statistical method/significance
• replication

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Define your Population

• Population the group researchers wish to study
• All humans?
• People with depression?
• Adolescents?

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Sampling

• Sample a subgroup of your population
• In order for results to be generalizable to the
  population, a sample must be representative (size
  is key)
• Random sample everyone in the population has an
  equal chance of being in your sample

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Independent and Dependent Variables
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Operational Definitions (for Variables)

• Definitions should be clearly defined and
  quantifiable
• Operational definitions reduce subjectivity and
  expectancy effects and allow for replication

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Confounding (Hidden) Variables

• Confounding variables - Variables in a study that
  are not controlled for (outside factors, e.g.?)
• Ways to control for confounding variables
• Large sample size (more apt to be representative)
• Random assignment to groups (control and
  experimental)
• Blinding - Single v. double
• Single controls for reactivity (observer effects)
• Double controls for expectancy effects (research
  bias)
• Placebos or sham treatment

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Experimentation Other Terminology

• Quasi-Experimental design "experiments that have
  treatments, outcome measures, and experimental
  units, but do not use random assignment to create
  the comparisons from which treatment-caused
  change is inferred." (Cook Campbell)
• A between-subject design Different subjects. This
  enables random assignment of subjects to
  conditions
• A within subjects design Same subjects where each
  is exposed to all of the conditions (uses
  repeated measures)

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Research pitfalls

• Experimenter Bias
• Self-fulfilling prophecy The experimenter arrives
  at conclusions that support his/her hypotheses
  based on the need to do so, not data
• Halo effects The tendency for people to transfer
  a positive opinion based on irrelevant
  information, i.e., people tend to think that more
  attractive people are also smarter

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Research pitfalls

• Observer effect (aka reactivity) the effect the
  experimenters presence has on subjects
• The Hawthorne effect is the tendency for change
  to occur simply because subjects are aware an
  experiment is being conducted
• Social desirability bias is the tendency for
  subjects to be able to respond in an experiment
  in a way that they believe would be most socially
  desirable

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Ethics in Experimentation

• APA Requirements/Guidelines - Ethical Principles
  of Psychologists and Code of Conduct (2002)
• Human experimentation must cause no harm
• Informed consent
• Confidentiality
• Debriefing
• Research institutions must have an Institutional
  Review Board (IRB)
• Role of deception? (Baumrind)

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Animal experimentation

• Controversies
• Institutional Animal Care and Use Committees
• Appropriate Beneficial and Caring (ABC)
  Guidelines
• Related Issues of anthropomorphism,
  generalization, and anthropocentrism