Chapter 2: Research Methodology
– scientific method: a systematic procedure of observing and measuring phenomena to answer
questions about what happens, when it happens, what causes it, and why.
– Theory (explanation based on observations) → hypothesis (prediction based on the theory) →
Research (test of the hypothesis; yields data, which either... support the theory (refine with new
hypothesis) or refute or fail to support the theory (discard or revise (and then test the revised
Scientific Method Depends on Theories, Hypothesis, and Research:
– theory: a model of interconnected areas and concepts that explains what is observed and makes
predictions about future events
+ explanation or a model of how something in the world works, consisting of interconnected
ideas and concepts
+ used to explain prior observation and to make prediction about future events
– hypothesis: a specific prediction of what should be observed in the world if a theory is correct
+ a specific, testable prediction about the outcome that would best support the theory.
+ if theory is reasonably accurate, the prediction framed in hypothesis should be supported
– research: scientific process that involves the systematic and careful collection of data
– data: objective observations or measurements
+ provides a test whether the hypothesis is likely to be supported.
– Replication: repitation of an experiment to confirm the results
+ repeating a study and getting the same/similar results
– a good theory should produce a wide variety of testable hypotheses.
Types of Studies in Psychological Research:
– Three types of designs: descriptive, correlational, and experimental
– variable: something in the world that can be measured and that can vary
+ experimenter either measures or manipulates
– descriptive studies (observational studies): manner in which data typically are collected involve
observing and noting behavior to analyze it objectively
– naturalistic observation: a passive descriptive study in which observers do not change or alter
+ observer makes no attempt to change the situation
– participant observation: a type of descriptive study in which the researcher is actively involved in
+ researcher involved in situation
– longitudinal studies: one type of developmental design
+ developmental changes that occurs over time (years?)
– observer bias: systematic errors in observation that occur because of an observer's expectations
+ cultural norms = problematic. Expects to believe what they already believe in..
– experimenter expectancy effect: actual change in the behavior of the people/animals being
observed that is due to observer bias.
– To protect against experimenter expectancy effects is to study blind.
Correlational Designs examine how variables are related
– correlational study: a research method that examines how variables are naturally related in the
real world, without any attempt by the researcher to alter them
+ rely on naturally occurring relationships
– directionality problem: when researchers find a relationship between two variables in a
correlational study, they cannot determine which variable may have caused changes in the other variable.
– Third variable problem: when experimenter cannot directly manipulate the independent variable
and therefore cannot be confident that another, unmeasured variable is not the actual cause of
differences in the dependent variable.
An experiment involves manipulating conditions
– experiment: a study that tests casual hypotheses by measuring and manipulating variables
– control (or comparison) group: the participants in a study that receive no intervention or an
intervention different from the one being studied
– experimental (or treatment) group: the participants in a study that receive the intervention
– independent variable: in an experiment, the condition that is manipulated by the experimenter to
examine its impact on the dependent variable
– dependent variable: in an experiment, the measure that is affected by the manipulation of the
– Confound: anything that affects a dependent variable and may unintentionally vary between the
experimental conditions of a study
Random assignment is used to establish equivalent groups:
– population: everyone in the group the experimenter is interested in
– sample: a subset of a population
– selection bias: when participants in different groups in an experiment differ systematically.
– Random assignment: the procedure of placing research participants into the conditions of an
experiment in which each participant has an equal chance of being assigned to any level of the
– meta-analysis: a “study of studies” that combines the findings of multiple studies to arrive at a
Data Collection Methods of Psychological Science:
– culturally sensitive research: studies that take into account the ways culture affects thoughts,
feelings, and actions.
Observing is an unobtrusive strategy
– observational techniques: a research method of careful and systematic assessment and coding of
+ watching and noting people's gestures during social interaction
– reactivity: when the knowledge that one is being observed alters the behavior being observed
+ noticing observer... changing behaviors?
Case studies examine individual lives and organizations
– involves the intensive examination of one person or a few individuals or one or a few
+ provide extensive data about one or a few individuals...
+ can get very subjective.
Asking takes a more active reproach
– self-report method: a method of data collection in which people are asked to provide information
about themselves such as in questionnaires or surveys
+ questionnaires to gather data from a large number of people
– response accuracy: measurable
+ attention improves perception of the stimulus
+ measure information while psychological tasks are being performed
+ measure reaction time, response accuracy, and ask participants to make stimulus judgments
Body/BrainActivity can be measured directly – psychophysiological assessment: researcher examine how bodily functions change in association
with behaviors/mental states
– electrophysiology: a data collection method that measures electrical activity in the brain
+ fits electrodes onto participant’s scalp.
+ picks up brain's electrical activity instead of sounds
– electroencephalograph (EEG): measures brain activity
+ useful = different behavioural states produce different and predictable EEG patterns
– event-related potential (ERP): patterns associated with specific events able to be observed.
– brain imaging: a range of experimental techniques that make brain structures and brain activity
+ measures changes in rate, or speed of blood flow.
– Position emission tomography (PET): a method of brain imaging that assesses metabolic activity
by using a radioactive substance injected into the bloodstream
+ uses glucose
+ as brain performs mental task, blood flow increases to the most active regions → emit more
– Magnetic resonance imaging (MRI): a method of brain imaging that produces high-quality images
of the brain
+ determining location of... brain damage. Creates images of the working brain
– functional magnetic resonance imaging (fMRI): a imaging technique used to examine changes in
the activity of the working human brain
+ map mental activity, scanning brains