Research in Psychology
 Psychology is defined as the
scientific study of ……
Types of Research
 Applied Research: Practical application..
 Clinical Research: Patient oriented,
psychological disorders…
 Basic Research: Expand knowledge, no
practical application
Why do we need research?
The Dangers of Common Sense
 Hindsight Bias or “I-knew-it-all-along”
 people tend to view events as more
predictable than they really were.
 Intuition :
 sensing without the use of rational process
 False Consensus effect – tendency to
overestimate others’ agreement with us
Overconfidence
 Confidence level: not a consistent predictor
of accuracy
 (We tend to remember our correct
predictions and disregard our wrong ones!)
The Scientific Attitude
 Curiosity
 Skepticism
 Humility
 Smart Thinking=Critical Thinking
 Theory
Research Strategies
 an explanation that organizes and predicts
observations
theories
 Hypothesis (If…, then…)
lead to
generate or refine
 a testable prediction often implied by a
theory
and
hypothesis
 Operational Definitions research
observations
 the specific procedures or steps used in the
research study
Scientific Method
 State the Problem
 Gather Information
 Form a Hypothesis
 Test the Hypothesis
 Record and Analyze Data
 State the Conclusion
 Repeat the Work
Types of Research
Correlational Studies
 Explores strength of a relationship
between two or more variables
 Can make predictions, but cannot
explain cause and effect
Types of Correlational Studies
Case Study
 In-depth study- one person / small
group
 Strength: provides valuable insight
on an issue / condition
 Weakness: findings can rarely be
generalized to a population
 Some exceptions…(Phineas Gage)
Correlational Studies….
Survey Method
 research the self-reported attitudes or
behaviors of people
 Questionnaire / Survey / interview...
 Strength: can be generalized to a
larger population (if sample is random)
 Weakness: No cause and effect
 Wording of survey can introduce bias
Correlational Methods
Random Samples
 Random Sample – when every person in
targeted population has equal chance of
participating.
 The larger the sample size the more likely to
represent the whole
 Ex. Computer generated list of every 5th
person.
 Why not send survey to the entire school?
Correlational Methods
Naturalistic Observation
 Observing subjects in natural
habitats / no interaction between
researcher and subjects
 Strength: valuable insight into
natural behavior
 Weakness: no cause and effect
Bias in Naturalistic Observation
 Observer Effect: Behavior can change
when being watched… (animals or
humans) AKA Hawthorne Effect
 Observer Bias:
 When researchers notice what they
want to see and ignore what doesn’t
support their theory
 Anthropomorphic Fallacy: Attributing
human thoughts, feelings, or motives to
animals during research (especially
when explaining behavior)
Bias in research…
 Experimenter Effects: Changes in
behavior caused by the unintended
influence of the experimenter
 Self-Fulfilling Prophecy: When
expectations affect outcome… (teachers..)
Correlational Research
Analyzing Data
 Correlation Coefficient: measures the
strength of a relationship.
 A Positive correlation: presence of one thing
predicts the presence of the other thing. (2
sets of scores rise or fall together:
+1=perfect correlation)
 A Negative correlation means the presence
of one thing predicts the absence of the
other thing. (one goes up, the other down: --1= perfect negative
Correlation Coefficients
 What is generally considered the lowest
correlation coefficient to hold statistical
significance?
 Provide one example of a perfect positive
correlation and one example of a perfect
negative correlation.
Correlations: Statistical Analysis
 Scatterplot (aka scattergram, scatter diagram)
 Graphed data that shows the strength of a
correlation
 The more the data forms a line, the stronger
the correlation, IOW:
 little scatter = high correlation
 extensive scatter = little or no correlation
 the slope of the line suggests a positive or
negative correlation
Research Methods
Perfect positive
correlation (+1.00)
No relationship (0.00)
Perfect negative
correlation (-1.00)
Fig. 1.9 The relationship
between years of college
completed and personal
income (hypothetical data).
95
Temperament 90
scores 85
80
75
70
65
60
55
50
45
40
35
30
25
55
Research Strategies
60
Height in inches
65
70
75
80
 Scatter plot of Height and Temperament
85
So…
 Correlation indicates the
possibility of a cause-effect
relationship, but it cannot prove
causation
Illusionary Correlation
 Illusionary Correlation – False assumption
of relationship between two things (tend to
recall instances that confirm our belief.)
 Examples:
 More babies born during a full moon
 infertile couples who conceive after they adopt
 premonition of a phone call followed by the phone
call
Remember…
 Correlational methods can be
used in case studies, surveys,
and field experiences.
Experimentation: Cause and Effect
 Experiment: the clearest way to
isolate cause & effect
 Experiments manipulate variables
to test the results
Know the Difference…
 Correlational studies uncover
naturally occurring relationships.
 experiments manipulates a
setting to determine its effect.
Key Experimental Principles
 Experimental group – Group that
receives the treatment
 Control group – Group that does
not receive the treatment (placebo)
 Each group must be from a random
sample, and randomly assigned
Variables (Anything that can vary…)
 Independent Variable (IV)
 the variable that is manipulated
(example, the drug)
 Dependent Variable (DV)
 the variable that is measured (example:
behavior, or memory)
….Variables
Determine the IV and DV in the
following hypothesis:
 If you give a child sugar, then
the child’s activity level
increases.
Confounding Variables

Inconsistencies between
experimental and control groups
that can skew the results (bias!)
 Examples: Time, place, frequency,
amount etc.
…Confounding Variables
 If you give a child sugar, then the child’s
activity level increases.
 What confounding principles might affect
this experiment?

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Scheduled activities after the experiment
Location of observed behavior
Peer group during experiment
Size of peer group during experiment
Amount and type of sugar ingested
Time of the experiment
Conditions prior to the experiment
Controls (steps to avoid confounding
variables)
 Placebos – “sugar pills” or any inert
substance given to control group (used as
comparative basis against the experimental
group)
 Single blind procedure: Subjects don’t
know which group they are in…
 Double-blind procedure – neither subjects
nor experimenter know which groups
subjects are in…
 Random sample and random assignment
Recording data…
 How do you record data when you are
trying to measure levels of a specific
behavior?
 Create a scale of 1-5 describing levels of a
specific behavior.
Remember…
 Experiments aim to manipulate an
independent variable, measure a
dependent variable, and control all other
variables.
Good Research is…
 Valid – when it measures what
the researcher set out to measure
and is accurate
 Reliable – when replication , with
same operational definitions,
results in the same outcome.