January 22 & 24 2014
PSYC 2002-B Introduction to Statistics in Psychology
Week three readings:
Pg. 91-144 (Chapter 5 sampling and probability)
Pg. 115-144 (Chapter 6 the normal curve standardization and z-scores)
Chapter 5 Key Terms:
Random sample: is one in which every member of the population has an equal chance of
being selected into the study.
Convenience sample: is one that uses participants who are readily available.
Generalizability: refers to researchers’ ability to apply findings from one sample or in one
context to other samples or contexts; also called external validity.
Volunteer sample: or self-selected sample is a special kind of convenience sample in
which participants actively choose to participate in a study.
Confirmation bias: is our usually unintentional tendency to pay attention to evidence that
confirms what we already believe and to ignore evidence that would disconfirm our
beliefs. Confirmation biases closely follow illusory correlations.
Illusory correlation: is the phenomenon of believing one sees an association between
variables when no such association exists.
Personal probability: refers to the likelihood of an event occurring based on an
individuals opinion or judgement; also called subjective probability.
Probability: is the likelihood that a particular outcome- out of all possible outcomes- will
The expected relative-frequency probability: is the likelihood of an event occurring based
on the actual outcome of many, many trials.
Trial- refers to each occasion that a given procedure is carried out.
Outcome- refers to the result of a trial.
Success- refers to the outcome for which we’re trying to determine the probability.
Control group: is a level of the independent variable that does not revi