Transcript Research Ethics - University of Alberta

Methods of Psychology
Objectives
• How are scientific methods applied to
psychological questions?
• Research Strategies:
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Design
Setting
Data-collection method
Advantages and Disadvantages
Objectives
• Measures of central tendency and variability
• Clinical vs. statistical significance
Clever Hans
• German horse – early 20th century
• Owner taught him math, english, history,
etc.
• Trained to answer questions
• Even so when owner not present
• Psychologist: Oskar Pfungst – skeptical
Clever Hans
• Experiment - use of blinders
• Hans failed to answer questions
• Following question requiring hoof tap –
questioner would look downward
• Counting questions – brown raising
signaled stop
• Head shake responses – similar movement
by questioner
Fact
• Fact: true for all observers, usually based on
direct observation
• In Psychology, usually particular
behaviours, or reliable patterns of
behaviours
Theory
• Idea or mental model designed to explain existing
facts or make predictions about future facts
(behaviours)
• Theory based predictions – Hypotheses
• (Educated Guesses)
• Von Osten’s hypotheses: Horses are as intelligent
as humans
• FACTS  THEORIES  HYPOTHESES 
EXPERIMENTATION  NEW FACTS
Lessons From Hans
1. Skepticism is GOOD
 A good scientist always tries to disprove
theories, especially his/her own.
Popular Wisdom vs. Science
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Home Field Disadvantage
Baumeister & Steinhilber (1984)
World Series games 1924-1982
Home team wins 60.2% - Games 1 & 2
Home team wins 38.5% of Game 7’s
Paradoxical effect of supportive audiences
in pressure situations
Popular Wisdom vs. Science
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The “Not-So-Hot-Hand” in Basketball
Tversky (1985)
The validity of “hot” shooting streaks
Probability of pro player making a basket
after a previous successful attempt
approximately 50%
Lessons From Hans
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Careful observation under controlled
conditions
Hallmark of the Scientific Method
Lessons From Hans
3. Observer-Expectancy Effects
 Researchers unintentionally influence
their subjects and data
Research Strategies
• Can be categorized along 3 dimensions
1. Research Design
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Descriptive
Correlational
Experimental
Research Strategies
2. Setting
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Field
Laboratory
Research Strategies
3. Data Collection Method
 Self Report
 Observational
Research Designs
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Descriptive Studies
Describes behaviour of individual or group of
individuals without manipulating or
controlling variables
May describe the prevalence of a disorder
without correlating disorders with other
characteristics (age, sex, SES)
Jane Goodall
James Tiberius Kirk
Descriptive Studies
Observing fans at sporting events
Recordings kids interactions during play
Correlational Studies
• Correlation: Relation between 2 or more
measured variables
• Sometimes, can’t manipulate/control
variables, all we can do is measure them
• Correlation coefficients range from
• -1.00 to +1.00
• Negative correlation < 0.00
• Positive correlation > 0.00
Interpreting Correlations
• The higher the coefficient – be it positive or
negative – the stronger the relationship
between 2 variables
• The closer the coefficient is to zero – be it
positive or negative – the weaker the
relationship/association between 2 variables
Cardinal Rule of Correlation
• CORRELATION does not imply
CAUSATION
• We can only describe a relationship, without
making any claims about whether one
variables causes or influences the other.
• Only that they tend to co-occur
Cardinal Rule of Correlation
• A study of married couples showed that
the longer they had been married, the
more similar their opinions were on social
and political issues.
Cardinal Rule of Correlation
• In a study of American cities, a
relationship was found between the
number of violent crimes and the number
of store selling violence-depicting
pornography.
Cardinal Rule of Correlation
• All children in an orphanage received an
IQ test. Results showed that the longer
the children had lived in the orphanage,
the lower their IQ scores.
Cardinal Rule of Correlation
• The more someone plays violent video
games (e.g., Doom), the more aggressive
they are in real-life
Cardinal Rule of Correlation
• The more churches there are in a
community, the more bars there are.
Advantages of Correlation
• May be more convenient to implement in
some situations
• May be permissible where ethical
considerations prohibit random
assignment of subjects
• May be conducted in a more naturalistic
setting
Advantages of Correlation
• May give you access to a larger subject
pool, since data are easier to collect than
in an experiment
Disadvantages of Correlation
• Can’t infer CAUSALITY
Examples of Correlation
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-0.032
+0.77
-0.82
0.00
Experimental Studies
• Experiments are controlled investigations
that study cause-and-effect relationships
through the manipulation of variables.
They allow for random assignment.
• An experimenter manipulates V1 (e.g.,
amount of grain alcohol consumed by a
person) and then measures V2 (e.g.,
amount of aggression displayed).
Experimental Studies
• The experimenter has total control over
the independent variable (IV).
• That is, the experimenter decides "how
much" of the IV the subject gets or the
condition to which the subject is assigned
Rigor - Relevance Trade Off
RIGOR <----------------------->RELEVANCE
Research Settings
1 Laboratory studies - this is when a researcher
sets up a controlled environment in which to
conduct an experiment
• Laboratory studies can be very effective at
making sure that observations are made
under controlled conditions
Milgram’s Obedience
Experiment
• 1961 - Investigate influence of authority
over free will
• Administer “shock” to a confederate
• “The experiment must continue”
• 2/3’s of subjects willing to administer
maximum shock
Field Experiments
• Sometimes it is impossible or impractical to
conduct research in a laboratory.
• For example, what if a researcher was
interested in people's behaviors while in
church? She could created a laboratory
environment that replicates the actual church
environment, but it is unlikely that people
would behave in this environment exactly the
same way as they would in a real church.
Piliavin, Rodin, & Piliavin
(1969)
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Bystander intervention
Accomplice falls in NYC subway
How many people would assist?
How quickly?
Varied race, intoxication, disability
Diffusion of responsiblity
Stanford Prison Experiment
• 1971
• Phillip Zimbardo
• http://www.prisonexp.org/
Data Collection Methods
• Self-report - many phenomena studied in
psychology can only be investigated by
asking people how they think or feel
• Questionnaires - this is where people
produce self-descriptions by checking off
items on a list or writing answers to essay
questions
Data Collection Methods
• Interviews - subjects describe thoughts,
feelings, behaviours orally
• structured vs. unstructured
• Naturalistic Observation - non-intrusive data
collection via observation of subjects in
natural enviornment
Descriptive Statistics
• Simply describe a set of numbers (data set)
• MEAN: mathematical average of set of
numbers
• MEDIAN: the “middle” number in data set
• MODE: the number that occurs most
frequently in the data set
Descriptive Statistics
• Variability
• Standard Deviation - most common
• SD simply the average distance of scores
from the mean
• How much, on average, scores differ from the
mean score
Inferential Statistics
• Descriptive stats only describe the data set
• Inferential stats attempt to make inferences
about the larger population
• Samples vs. Population
• problem of university students
Error Variance
• Data will also be influenced by naturally
occurring variability
• Shrinkage
• Laws of probability - statistical significance
Statistical Significance
• Inference being assessed is the Hypothesis
• Falsification in scientific method
• Inferential stats investigate the probability
that the hypothesis is WRONG
• Tell us how likely it is that we would find
the results we found due to chance alone
• Arbitrary but conservative 95% certainty
Statistical Significance
• Based on…
• Size of the observed effect
• Number of individual observations
• Variability
• STATISTICAL SIGNIFICANCE DOES NOT
EQUATE WITH CLINICAL SIGNIFICANCE
Bias
• Error refers to random variability in results
• Bias refers to non-random effects caused by
factors unrelated to research hypotheses
• Sampling Bias
• If pre-existing, systematic differences exist
between groups ad hoc, then results may be
biased
• Treatment completers; clinical populations
Bias
• Measurement Bias
• Researchers try to ensure that their
measures are both Reliable and Valid
• Reliability = consistency
Bias
• Validity - that the measure actually assesses
that which it is designed to assess
• Face Validity - does it appear to measure
what it purports to measure?
• E.g., Rorschach; Empathy scales
Bias
• Criterion Validity - How strongly do scores
on a given measure correlate with another
“valid” measure?
• Predictive Validity - How well does the
measure predict the behaviour that it is
associated with?
• E.g., risk assessment measures (offenders,
at-risk kids)
Personality Test
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http://haleonline.com/psychtest/
http://www.colorquiz.com/
Observer-Expectancy Effects
• Clever Hans
• Experimenter can inadvertently influence
his/her subjects
• Blind experiments
Subject-Expectancy Effects
• Subject may also alter behaviour based on
perceived expectations (oregano example)
• Jury Duty/Military Draft vs. Job
Application
Hawthorne Effect
• Hawthorne Plant of Western Electric
Company
• Effects of work environment on
productivity
• lighting, humidity, break times, etc.
Subject-Expectancy Effects
• Regardless of experimental manipulation
implemented, worker productivity improved
• Concluded workers invigorated by interest
of the researchers
• Or, simply worked harder when under the
microscope
• Double Blinds and Placebos
Research Ethics
• Human subjects: Psychological science
depends largely upon willing human
participants Without them, how would we
ever learn anything?
• Therefore, respecting the rights, safety
and privacy of research participants is of
the utmost importance.
Research Ethics
• Three are three primary issues to consider
when conducting research with humans
1 Rights to privacy - the privacy rights of
participants are maintained by obtaining
informed consent, allowing participants to
quit at any time without penalty and
keeping records and data confidential and
secure
Research Ethics
2 Deception - is it ethical to deceive people
in psychological research?
• How can we avoid expectancy effects if
participants are completely informed
about the research and its hypotheses?
• Some researchers view all deception as
unethical, yet others believe that it must
be done in some cases, but done carefully
and respectfully
Research Ethics
3 Possible discomfort or harm - participants
in research must always be informed of
any possible physical or psychological
harm that might result from their
participation in the research
• Debriefing and access to services
Research Ethics
• Informed consent
Research Ethics
• Animals: Most people agree that
procedures that cannot ethically be done
to humans can be done with animals.
• Others believe that animals should have
the exact same rights as humans and,
since they are unable to give consent,
should never be used in psychological
research.
Research Ethics
• It is a fact that humans have benefited
greatly from research conducted with
animals
• American Psychological Association has
established a set of principles guiding the
use of animals in research to protect them
as much as is possible