Chapter 2 Psychology Notes
September 18, 2013
5:39 PM
What makes research scientific
Precision
Start out with a theory, then a hypothesis is derived
Theory: organized system of assumptions and principles that purports to explain a specified set of
phenomena and their interrelations
Hypothesis: a statement that attempts to predict or account for a set of phenomena; scientific
hypotheses specify relations among events or variable and are empirically tested
Operational definition; a precise definition of a term in a hypothesis which specifies the
operations for observing and measuring the process or phenomenon being defined
Skepticism
Means treating conclusions, both new and old with caution, which must be balanced by openness
to new ideas and evidence
Reliance on Empirical evidence
A hypothesis must be backed by empirical data to prove that it is true
Willingness to make risky predictions
A statement must be worded in a way that that it can be refuted by others.
Principle of falsifiability; the principle that scientific theory must make predictions that specific
enough to expose the theory t the possibility of disconfirmation; that is, the theory must predict
not only what will happen but what will not happen
This principle is often violated because of confirmation bias
Confirmation bias; the tendency to look for or pay attention only to information that confirms
one's own belief
Openness
Secrecy is a big no-no
Other scientists must know how to replicate others work so that they may come to the same
conclusions
All these principles create "good science".
Openness to new ideas encourages questions to be asked, and the consideration of other views, while
reliance on empirical evidence helps scientists avoid oversimplification. Falsifiability forces scientists To
analyze assumptions and biases, and until the results have been replicated and verified scientists must
deal with uncertainty
Peer review; scientists submit results to a professional journal, which then sends their findings to other
experts in the field for evaluation before publishing them
Descriptive Studies: Establishing the Facts
Representative sample: a group of individuals selected from a population for study, which
matches the population on important characteristics such as age and sex
Descriptive methods; methods that yield descriptions of behaviour but not necessarily casual
explanations
Case study; a detailed description of a particular individual being studied or treated
Genie case study; page 43 Observational studies; a study in which the researcher carefully and systematically observes and
records behaviour without interfering with the behaviour; it may involve either naturalistic or
laboratory observation
These studies involve many people
Naturalistic observation; discovering how people or animals act in their normal social
environments
Researchers count, rate, or measure behaviour systematically staying away from preconceived
notions
Laboratory observation; is within a lab itself with sophisticated equipment, a certain number of
participants etc
Psychological tests/ assessment instruments; procedures used to measure and evaluate
personality traits, emotional states, aptitudes, interests, abilities and values
Standardize; in test construction, to develop uniform procedures for giving and scoring a test
Norms; in test construction, established standards of performance
Reliability; the consistency of scores derived from a test, from one time and place to another
Validity; the ability of a test to measure what it was designed to measure
Test- retest reliability; giving a test twice to a test group and seeing how the answers change or
do not change
Alternate-forms reliability; giving the same test twice but slightly altered on the same time to
determine if results change
Criterion validity; the ability to predict independent measure or criteria of the trait in question, eg
for a scholastic aptitude test the criterion would be grades
Surveys; questionnaires and interviews that ask people directly about their experiences,
attitudes, or opinions
Often have sampling issues, because it is hard to get the population as whole
Volunteer bias; a shortcoming of findings derived from a sample of volunteers instead of a
representative sample; the volunteers may differ from those who did not volunteer
Another issue with surveys is lying, whether out f fun, or to not be stereotyped in a negative way
Survey also depends on how the question was phrased, and what the question was about
Internet surveys make the test subject feel more secure, but it is hard for researchers to know if
participants understand the questions
Correlational Studies: Looking for Relations
Correlational study; a descriptive study that looks for a consistent relation between two
phenomena
Correlation; measure of how strongly two variables are related to one another
Variables; characteristics of behaviour or experience that can be measured or described by a
numerical scale
Positive correlation; an association between increases in ne variable and increases in another- or
between decreases in one and in another
Negative correlation; an association between increases in one variable and decreases in another
Coefficient of correlation; a measure of correlation that rangers in value from -1.00(perfect
negative) to +1.00(perfect positive)
If there is no relation between two variables they are uncorrelated or have zero correlation. If the
correlation between two variables is plus or minus .80 they are strongly positively/negatively
related
Cautions about Correlation;
Illusory correlations; apparent associations between two things that are not really related "a correlation does not establish causation"; if variable A predicts variable B, A must be
causing B, but that is not necessarily so
Experimental Variables;
Experiment; a controlled test of a hypothesis in which the researcher manipulates one variable to
discover its effect on another
o
Independent variable- a variable that an experimenter manipulates
o dependent variable- a variable that the experimenter predicts will be affected by
manipulations of the independent variable
o every experiment has at least one independent and dependent variable
o
everything in the experimental situation is constant except for the independent
o holding everything but the independent variable constant ensures that whatever happens is
due to the researcher's manipulation and nothing else- rule out interpretations
o control condition- a comparison condition in which participants are not exposed to the same
treatment as in the experimental condition (not exposed to the same treatment or
manipulation)
o random assignment- a procedure for assigning people to experimental and control groups in
which each individual has the same probability as any other of being assigned to a given
group (separating the group into even sides, with the same characteristics)
o in some situations the same people can be used in both the control and experimental
conditions ( they act as their own control)
o idea of the experiment is to have people of the same characteristics to either be in the
experimental or control group in order to identify the researcher's theories
o placebo- an inactive substance or fake treatment used as a control in an experiment or given
by a medical practitioner to a patient
o if the placebo works it is due to the participants expectations and not the treatment control
groups are crucial in nonexperimental studies
o for example- girls have self-esteem problems as soon as they hit adolescence, but without
figuring out a theory for boys as well, there is no way of knowing if self-esteem is just for girls
or for the boys as well
o
single-blind study- an experiment in which participants do not know whether they are in an
experiment or control group
o participants should not know which group they are in as to not create a bias
o as well as researchers with biases, hopes and expectations
o
Robert Rosenthal (1966) demonstrated how powerful such experimenter effects can be
o he had his students do an experiment with 'maze bright' and 'maze dull' rats, the maze bright
rats did better because of the way they were being treated by the students
o experimenter effects- unintended changes in study participants' behaviour due to cues
inadvertently given by the experimenter
o solution to experimenter's effects is the double-blind study
o double-blind study- an experiment in which neither the people being studied nor the
individual's running the study know who is in the control group and who is in the experimental
group until the results are tallied
o essential during drug tests, the administrator and the patient have no idea what code (on the
drug) it is until after the test is finished
o because experiments allow for cause and effect, they have been the method of choice for
psychology
o limitations- subjects are university students and do not represent the rest of the population,
the participants are put into an artificial situation and try to do what they are told as best they
can, they would not act as they normally would (Kihlstrom, 1995)
o
field research- descriptive or experimental research conducted in a natural setting outside the
laboratory
o (Mehl et al., 2007) experiment to see if women are more talkative than men
Research Methods in Psych Disadvantages
Advantages
Case Study Provides in depth info Vital info may be
shed light on situations/ missing, hard to interpret
problems that are unethical or memories may be
impractical selective/inaccurate
may not be
representative/ typical
Naturalistic Description of behaviour in Little or no control over
observation natural environment situations
useful in first stages of
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