1) The scientific approach to behaviour
a. Goals of the scientific enterprise: three sets of interrelated
i. Measurement and description: measure the phenomenon under
study. The first goal of psychology is to develop measurement
techniques that make it possible to describe behaviour clearly and
ii. Understanding and prediction: understand events when they can
explain the reasons for the occurrence of the event. Hypothesis: a
tentative statement about the relationship between two or more
variables. Variables are any measurable conditions, events,
characteristics, or behaviours that are controlled or observed in a
iii. Application and control: design a scientific examination of the
intervention’s effectiveness. Construct theory: a system of
interrelated ideas used to explain a set of observation. Theories
permit psychologists to make the leap from the description of
behaviour to the understanding of behaviour. A scientific theory
must be testable. Most theories are too complex to be tested all at
theory: a coherent
revise refinethe predictionsderived
theory from the theory
confidencein conductstudy to
theory decreases test hypotheses
Discard the theory Confidence in
theory increase b. Steps in a scientific investigation: systematic
i. Formulate a testable hypothesis: translate a theory or an intuitive
idea into a testable hypothesis. To be testable, scientific
hypotheses must be formulated precisely, and the variables under
study must be clearly defined. Researchers achieve these clear
formulations by providing operational definitions of the relevant
variables. An operational definition describes the actions or
operations that will be used to measure or control a variable.
Operational: establish precisely what is meant by each variable in
the context of a study.
ii. Select the research method and design the study: how to put the
hypothesis to an empirical test. Participants, or subjects, are the
persons or animals whose behaviour is systematically observed in
iii. Collect the data: researchers use a variety of data collection
techniques: direct observation, questionnaire, interview,
psychological test, physiological recording, and examination of
archival records, which are procedures for making empirical
observations and measurements.
iv. Analyze the data and draw conclusions: the observations made in a
study are usually converted into numbers, which constitute the
raw data of the study. Use statistics to analyze their data and to
decide whether their hypotheses have been supported.
v. Report the findings: write up a concise summary of the study and
its findings. A journal is a periodical that publishes technical and
scholarly material, usually in a narrowly defined area of inquiry.
Critique new research finds by other scientist.
vi. Key data collection techniques in psychology
d. Advantages of the scientific approach: two
i. Its clarity and precision: commonsense notions about behaviour
tend to be vague and ambiguous. The scientific approach requires
that people specify exactly what they are talking about when they
ii. Its relative intolerance of error (greatest): demand objective data
and thorough documentation before they accept ideas. iii. Research methods consist of various approaches to the
observation, measurement, manipulation, and control of variables
in empirical studies.
2) Looking for causes: experimental research: experiment is a
research method in which the investigator manipulates a variable
under carefully controlled conditions and observes whether any
changes occur in a second variable as result.
a. Independent and dependent variables (Dutton and Aron)
i. An independent variable is a condition or event that an
experimenter varies in order to see its impact on another variable.
Experimenter controls or manipulates this. It is free to be varied.
ii. Dependent variable is the variable that is thought to be affected by
manipulation of the independent variable.
b. Experimental and control groups: two (David Wolfe)
i. The experimental group consists of the subjects who receive some
special treatment in regard to the independent variable.
ii. The control group consists of similar subjects who do not receive
the special treatment given to the experimental group.
c. Extraneous variables (Dutton and Aron)
i. Extraneous (secondary, nuisance) variables are any variables
other than the independent variable that seem likely to influence
the dependent variable in a specific study.
ii. Confounding of variables occurs when two variables are linked
together in a way that makes it difficult to sort out their specific
iii. Random assignment of subjects occurs when all subjects have an
equal chance of being assigned to any group or condition in the
d. Variations in designing experiments
i. It is sometimes advantageous to use only one group of subjects
who serve as their won control group. The effects of the
independent variable are evaluated by exposing this single group
to two different conditions—an experimental condition and a
control condition. This approach would ensure that the
participants in the experimental and control conditions would be
alike on any extraneous variables involving their personal
ii. It is possible to manipulate more than one independent variable in
a single experiment. The main advantage of this approach is that it
permits the experimenter to see whether two variables interact.
An interaction means that the effect of one variable depends on the
effect of another.
iii. It is also possible to use more than one dependent variable in a
e. Advantages and disadvantages of experimental research
i. Its principal advantage is that it permits conclusions about cause-
and-effect relationships between variables.
ii. Researchers are able to draw these conclusions about causation
because the precise control available in the experiment allows them to isolate the relationship between the independent variable
and the dependent variables, while neutralizing the effects of
extraneous variable. No other can do it.
iii. The experimental method can’t be used to explore some research
iv. Limitation: experiments are often artificial. This approach allows
the experimenter to manipulate a variable, however, critics have
pointed out that having a participant read a short case summary
and make an individual decision cannot really compare to the
complexities of real trials. When experiments are highly artificial,
doubts arise about the applicability of findings to everyday
behaviour outside the experimental laboratory. Ethical concerns
and practical realities preclude experiments on many important
3) Looking for links: descriptive/correlational research
a. Naturalistic observation (Lavine and Norenzayan, 1999)
i. In naturalistic observation, a researcher engages in careful
observation of behaviour without intervening directly with the
ii. The major strength of naturalistic observation is that it allows
researchers to study behaviour under conditions that are less
artificial than in experiments. Can be good place to start when little
is known about phenomena under study.
iii. A major problem with this method is that researchers often have
trouble making their observations unobtrusively so they don’t’
affect their participants’ behaviour. Can’t explain why certain
patterns of behaviours were observed.
b. Case studies (Henriksson, Finland 1993)
i. A case study is an indepth investigation of an individual subject.
ii. When this method applied to victims of suicide, the case studies
are called psychological autopsies.
iii. Interviewing people, direct observation examination of records
and psychological testing.
iv. Clinical psychologists, who diagnose and treat psychological
problems. Routinely do case studies of their clients. But they are
not conducting empirical research.
v. Case study research typically involves investigators analyzing a
collection of case studies to look for patterns that permit general
vi. The main strength of case studies is it can provide compelling,
real-life illustrations that bolster a hypothesis or theory. It is also
particularly well suited for investigating certain phenomena, such
as psychological disorders and neuropsychological issues.
vii. The main problem: highly subjective. It is easy for investigator to
see what they expect to see in case study research.
i. Survey: researchers use questionnaires or interviews to gather
information about specific aspects of participants’ behaviour. ii. The main strengths: Surveys are often used to obtain information
on aspects of behaviour that are difficult to observe directly. It is
also make it relatively easy to collect data on attitudes and
opinions from large samples participants.
iii. The main problem with survey is that they depend on self-report
data. In addition, not all surveys are conducted with care. They are
often unreliable, due to intentional deception, social desirability
bias, response sets, memory lapses, and wishful thinking.
i. Psychological tests, sometimes called assessment instruments, are
procedures for measuring and evaluating personality traits,
emotions, aptitudes, interests, abilities, and values.
ii. Objective tests, also called inventories, measure beliefs, feelings, or
behaviours of which an individual is aware.
iii. Projective tests are designed to tap unconscious feeling or motives.
iv. One test of a good test is whether it is standardized—whether
uniform procedures exist for giving and scoring the test.
v. Norms: in test construction, established standard of performance.
vi. For one thing the test must be reliable—that is, it must produce
the same results from one time and place to the next or from one
scorer to another.
vii. To be useful, a test must also be valid, which means that it must
measure what it sets out to measure.
e. Advantages and disadvantages of descriptive/correlational
i. Advantage: They give researchers a way to explore questions that
could not e examined with experimental procedures. This method
broadens the scope of phenomena that psychologists are able to
ii. Disadvantages: investigators cannot control events to isolate cause
and effect. Consequently, correlational research cannot
demonstrate conclusively that two variable are causally related.
4) Looking for conclusions: statistics and research: statistics is the
use of mathematics to organize summarize, and interpret
a. Descriptive statistics: are used to organize a summarize data.
Provide an overview of numerical data.
i. Central tendency: the score that falls exactly in the center of a
distribution of scores. Mean (most useful but is sensitive to
extreme scores): the arithmetic average of the scores in a
distribution. Mode: the most frequent score in a distribution.
ii. Variability: refers to how much the scores in a data set vary from
each other and from the mean. Standard deviation: index of the
amount of variability in a set of data. High variability leads high
iii. Correlation: exists when two variables are related to each other.
Correlation coefficient is a numerical index of the degree of
relationship between two variables. It indicates: the direction (positive or negative) of the relationship and how strongly the two
variables are relative.
iv. Positive versus negative correlation: (only direction not strength)
1. Positive: two variables co-vary in the same direction.
2. Negative: two variables co-vary in the opposite direction.
v. Strength of the correlation: the size of the coefficient indicates the
strength of an association between two variables. The strength of a
correlation depends only on the size of the coefficient. +1.00 or -
1.00 indicates a perfect, one to one correspondence between the
two variables. Near 0 indicates no relationship between the
vi. Correlation and prediction: as a correlation increases in strength
(get closer to either -1