Chapter 2 – Studying Behaviour Scientifically
Curiosity, skepticism, and open-mindness are driving forces behind scientific inquiry
Diffusion of responsibility: each person feels decreased personal responsibility for
intervening (ex: girl being raped when walking back to apartment, none of her neighbour
call 911even though they knew what’s happening)
Gathering Evidence: Steps in the Scientific Process
1) Initial Above example. Why did no one help?
Observation/
Question
2) Form IF bystanders are present, THEN a diffusion of responsibility
Hypothesis will decrease each bystander’s likelihood of intervening. (If-
Then statement)
3) Test - create “emergency” in controlled setting
Hypothesis by - manipulate perceived number of bystanders
gathering - measure helping
evidence
4) Analyze Data Helping decreases as the perceived number of bystanders
increases. The hypothesis is supported. (if data do not support
hypothesis, revise and retest)
5) Further Additional studies support the hypothesis.ATheory of Social
Research and Impact is developed based on these and other findings.
Theory Building
6) New The theory is tested directly by deriving a new hypothesis and
Hypothesis conducting new research.
Derived from
Theory
Hypothesis: tentative explanation or prediction about some phenomenon
Theory: set of formal statements that explains how and why certain events are related to
one another
- Hindsight (after-the-fact) explanation is common method of trying to understand
behaviour (living forwards, understanding backwards)
- Hindsight explanation based on past events, which can be explained in many different
ways, but they also provide chances so that further scientific inquiry can be built
- Scientists want to understand the causes of a given behaviour so that they can predict
and then control those conditions
- Good theories generate an integrated network of predictions
Characteristics of good theories:
- organizes information in a meaningful way
- testable
- predictions made are supported by findings of new research
- conforms the law of parsimony (simpler) - although scientists use prediction as a test of “understanding”, it doesn’t mean that
prediction requires understanding
Variable: any characteristics that can differ (ex: gender, age, ethnicity, school grades, etc)
Operational definition: defines a variable in terms of specific procedures used to
produce or measure it
Self-report measures: ask people to report on their own knowledge, beliefs, feelings,
experiences, or behaviour
Social desirability bias: tendency of participants to give an answer that gives a good
impression rather than one that reflects how they truly feel or behave
Archival measures: past records which contain information about some type of
behaviour
Descriptive methods: involve recording observations or surveys
Correlational methods: involve measuring the strength of an association between two or
more events
Experimental methods: involve manipulations to establish cause and effect relationships
two or more events
Case study: an in-depth analysis of an individual, group, or event
Advantages of using case studies:
- enable scientists to study and collect data when rare phenomenon occurs
- may challenge validity of a theory or scientific belief
- illustrate intervention programs to treat special populations
Limitations on case studies:
- poor method for determining cause-effect relations (ex: treatment causing infant’s
weight gain)
- generalization of the findings [may not be trustable] (ex: solution may only work for
that person)
- lack of objectivity in the way that researcher gathers and interprets data (ex: bias
since different views)
Naturalistic observation: way that researcher observes behaviour in a natural setting and
tries to avoid influencing the participants when being observed
Survey research: information about a topic is obtained by administering questionnaires
or interviews to many people Key concepts of making a survey research: population and
sample
Population: consist of all individuals about whom we are interested in drawing a
conclusion
Sample: a subset of individuals drawn from the larger population of interest
Representative sample: one that reflects the important characteristics of the population
Random sampling: every member of the population has an equal probability of being
chosen to participate in the survey Advantages of surveys: efficient method for collecting a large amount of information
about people’s opinion and lifestyles
Three drawbacks to surveys:
- unrepresentative samples can lead to faulty generalizations about how an entire
population would respond
- rely on participants’self-reports (have to assume sample doesn’t lie)
- cannot be used to draw conclusion about cause and effect
Correlational research: research that measures two or more naturally occurring
variables and examines whether they are statistically related (relation between X and Y)
Correlation coefficient: statistic that indicates the direction and strength positively or
negatively
Positive correlation: higher scores on one variable are associated with higher scores on a
second variable
Negative correlation: higher scores on one variable are associated with lower scores on a
second variable
- correlation coefficient range from values of +1.00 to -1.00 (+/- represents direction)
- zero correlation means X and Y are not related statistically
Characteristics of an experiment:
- researcher manipulates one variable
- researcher measures whether this manipulation produces changes in a second variable
- researcher attempts to control for extraneous factors
Independent variable: factor that is manipulated by the experimenter
Dependent variable: factor that is measured by the experimenter and may be influenced
by the independent variable
Experimental group: group that receives a treatment or
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