02. Definitions Flashcards
An observation
an objective statement that reasonable observers agree is true
Theory
an idea or a conceptual model that is designed to explain existing observations and make predictions about new observations that might be discovered
Hypothesis
prediction about a new observation that is made from a theory
Parsimony/ Occam’s razor
The simpler the explanation is the better it tends to be. When there are two or more explanations, the simplest explanation is usually preferred.
Experiment (cause-effect)
A procedure in which a researcher systematically manipulates (varies) one or more independent variables and looks for changes in one or more dependent variables, while keeping all other variables constant. Most direct and conclusive approach to testing a hypothesis about a cause-effect relationship between two variables
Variable
anything that can change or assume different values (condition or measure of behaviour)
Independent variable
The variable that is hypothesised to cause some effect on another variable (usually factors which influence behaviour)
Dependent variable
he variable that is hypothesised to be affected (usually a measure of behaviour)
Within subject experiment
(Sometimes repeated-measures experiments), each subject is tested in each of the different conditions of the independent variable (that is, the subject is repeatedly tested)
Between-groups experiments
(Sometimes, between-subjects experiments), there is a separate group of subjects for each different condition of the independent variable.
Correlational study
study in which the researcher does not manipulate any variable, but observes or measures two or more already existing dependent variables to find relationships between them.
Descriptive study
The description of the behaviour of an individual or set of individuals without assessing relationships between different variables (may or may not use numbers). May be broad or narrow in focus.
Laboratory study
any research study in which the subjects are brought to a specially designated area that has been set up to facilitate the researcher’s collection of data or control over environmental conditions
Field study
any research study conducted in a setting where the researcher does not have control over the subjects’ experiences
Self -report methods
procedures in which people are asked to rate or describe their own behaviour or mental state in some way
Introspection
Form or self-report. The personal observations of one’s thoughts, perceptions, and feelings (used by founders of psychology inc. Wilhelm Wundt).
Observational methods
All procedures by which researchers observe and record the behaviour of interest rather than relying on subjects’ self-reports.
Test
Subcategory of observational methods- the researcher deliberately presents problems, tasks, or situations to which the subject responds
Naturalistic observation
Subcategory of observational methods- the researcher avoids interfering with the subjects’ behaviour
Hawthorne effect
Changes in subjects’ behaviour as a result of knowing they are being watched
Descriptive statistics
Are used to summarize sets of data
Inferential statistics
Help researchers decide how confident they can be in judging whether the results observed are due to chance. Ways of answering a question using the laws of probability
Mean
the arithmetic average
Median
The centre score (arrange numbers from lowest to highest)
Variability
the degree to which the numbers in the set differ from one another and from their mean
Standard deviation
Measure of variability. The farther most scores are from the mean, the greater the standard deviation.
Correlation coefficient (inferential statistics)
a statistic to measure the strength and direction of the relationship between two variables. Produces a result from -1.00 to +1.00 (close to 0 = statistically unrelated)
Positive correlation
an increase in one variable coincides with a tendency for the other variable to increase (towards +1.00)
Negative correlation
an increase in one variable coincides with a tendency for the other variable to decrease (towards -1.00)
Define p (probability)
Level of significance. Probability that a difference as great as or greater than that observed would occur by chance
Bias
refers to nonrandom (directed) effects caused by some factor or factors extraneous to the research hypothesis
Biased Sample
Occurs when the members of a particular group are initially different from those of another group in some systematic way, or are different from the larger population that the researcher is interested in
Define WEIRD
Western, Educated, Industrialised, Rich and Democratic
Reliability
has to do with measurement error, not bias. A measure is reliable to the degree that it yields similar results each time it is used with a particular subject under a particular set of conditions, sometimes referred to as replicability
interobserver (or interrater) reliability
the same behaviour seen by one observer is also seen by a second observer. This requires that the behaviour in question be carefully defined ahead of time
operational definition
The specification of exactly what constitutes an example of your dependent measure
Validity
A measurement procedure is valid if it measures or predicts what it is intended to measure or predict. A procedure may be reliable and yet not be valid. Lack of validity can be a source of bias.
face validity
If the measurement procedure appears to assess the variable that it is supposed to measure
Observer-expectancy effects
A researcher who wants or expects a subject to respond in a particular way may unintentionally communicate that expectation and thereby influence the subject’s behaviour
Autism
A disorder characterised by a deficit in the ability to form emotional bonds and to communicate with other people; it typically manifests before age 3
Blind
In scientific research, the condition in which those who collect the data are deliberately kept uninformed about aspects of the study’s design (such as which subjects have had which treatment) that could lead them either unconsciously or consciously to bias the results
Subject-expectancy effects
If different treatments in an experiment induce different expectations in subjects, then those expectations, rather than anything else about the treatments, may account for observed differences in how the subjects respond
Double-blind experiment
An experiment in which both the observer and the subjects are blind with respect to the subjects’ treatment conditions.
Criterion validity
A measure has criterion validity if it correlates significantly with another, more direct measure of the variable
