•replication Repetition of an experiment to conﬁrm the results.
•theory A model of interconnected ideas and concepts that explains what is observed
and makes predictions about future events.
•hypothesis A speciﬁc prediction of what should be observed in the world if a theory
•research Scientiﬁc process that involves the systematic and careful collection of
•data Objective observations or measurements.
•variable Something in the world that can be measured and that can vary.
•operational deﬁnition The quantiﬁcation of a variable that allows it to be measured.
•experiment A study that tests causal hypotheses by measuring and manipulating
•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 manipulation
of the independent variable.
•confound Anything that affects a dependent variable that may unintentionally vary
between the different experimental conditions of a study
•random assignment The procedure for 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 independent variable.
•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.
•third-variable problem When the 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.
•descriptive study A research method that involves observing and noting the
behaviour of people or other animals in order to provide a systematic and objective
analysis of behaviour.
PSY100 Chapter 2 Research Methodology
•naturalistic observation A passive descriptive study in which observers do not
change or alter ongoing behaviour.
•participant observation A type of descriptive study in which the researcher is
actively involved in the situation.
•observational technique A research method of careful and systematic assessment
and coding of overt behaviour
•reactivity The effect that occurs when the knowledge that on eis being observed
alters the behaviours being observed.
•observer bias Systematic errors in observation that occur due to an observer!s
•experimenter expectancy effect Actual change in the behaviours of the people or
animals being observed that is due to observer bias.
•self-report method A method of data collection in which people are asked to provide
information about themselves, such as in questionnaires or surveys.
•socially desirable responding When people respond to a question in a way that is
most socially acceptable or that makes them look good.
•case study A research method that involves the intensive examination of one
•response performance A research method in which researchers quantify perceptual
or cognitive processes in response to a speciﬁc stimulus.
•reaction time A quantiﬁcation of performance behaviour that measures the speed of
•psychophysiological assessment A research method that examines how changes
in bodily functions are associated with behaviour or mental state.
•electrophysiology A method of data collection that measures electrical activity in
•positron emission tomography (PET) A method of brain imaging that assesses
metabolic activity by using a radioactive substance injected into the bloodstream.
•magnetic resonance imaging (MRI) A method of brain imaging that produces high-
quality images of the brain.
PSY100 Chapter 2 Research Methodology
1, indicating the strength and direction of the relation between two variables: inferential statistics a set of procedures used to make judgments about whether differences actually exist between sets of numbers. www. notesolution. com. What is scienti c inquiry: scienti c questions can be objectively answered: scienti c inquiry relies on objective methods and empirical evidence to answer testable question, the empirical process depends on theories, hypotheses, and research: Interconnected ideas or models of behaviour (theories) yield testable predictions (hypotheses), which are tested in a systematic way (research) by collecting and evaluating evidence (data). What are the data-collection methods of psychological science: observing is an unobtrusive strategy: data collected by observation must be clearly de ned and systematically collected. These self-report data may be biased by the respondents needs to present themselves in a particular way: case studies examine individual lives: an intensive examination of an individual is useful for examining unusual participants and research questions.