AP Psychology – Research Methods
• Differentiate types of research
(e .g ., experiments, correlational studies, survey
research, naturalistic observations, case studies) with regard to purpose, strengths, and weaknesses
Purpose:To find cause-and-effect.
Weaknesses: More costly. Ethical factors may make experiments impractical.
Purpose:To find out if two things go together, if they co-relate. Strengths:Can handle large numbers of people/data. Can often be done when ethical factors won’t allow experiments.
Weaknesses: Doesn’t show causation.
Purpose:To gather information.
Strengths: Inexpensive. Can gather lots of info fast. Can often be done when ethical factors won’t allow experiments.
Weaknesses: Wording and personal bias can severely alter results. Doesn’t show causation.
Purpose: To gather information.
Strengths: Inexpensive. Can often be done when ethical factors won’t allow experiments.
Weaknesses: Individual cases can be misleading. Doesn’t show causation.
Purpose:To gather information.
Strengths:Inexpensive. Requires only one participant. Can often be done when ethical factors won’t allow experiments.
Weakness: Individual cases can be misleading. Doesn’t show causation.
the tendency to believe, after learning an outcome, that one would have foreseen it
thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions.
an explanation using an integrated set of principles that organizes and predicts observations
a proposal intended to explain certain facts or observations
a statement of the procedures used to define research variables
repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances
a belief that others share the same opinion about something, when actually most don’t
all the cases in a group, from which samples may be drawn for a study
a sample that fairly represents a population because each member has an equal chance of inclusion
A statistical measure of the extent to which two factors vary together, and thus of how well either factor predicts the other
a graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggests the direction of the relationship between the two variables. The amount of scatter suggests the strength of the correlation (little scatter indicates high correlation). (Also called a scattergram or scatter diagram.)
the perception of a relationship where none exists
an experimental procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo. Commonly used in drug-evaluation studies.
experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which is assumed to be an active agent
the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable
the condition of an experiment that contrasts with the experimental condition and serves as a comparison for evaluating the effect of the treatment
assigning participants to experimental and control conditions by chance, thus minimizing preexisting differences between those assigned to the different groups
the experimental factor that is manipulated; the variable whose effect is being studied
the outcome factor; the variable that may change in response to manipulations of the independent variable
The number that occurs most often in a set of data
the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores
The middle number in a set of numbers that are listed in order
the difference between the highest and lowest scores in a distribution
a computed measure of how much scores vary around the mean score
a statistical statement of how likely it is that an obtained result occurred by chance
the enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next
the extent to which a test yields consistent results, as assessed by the consistency of scores on two halves of the test, on alternate forms of the test, or on retesting
the extent to which a test measures or predicts what it is supposed to
in an experiment, a variable, other than the independent variable, that could influence the dependent variable
giving participants in a research study a complete explanation of the study after the study is completed
defining meaningful scores by comparison with the performance of a pretested standardization group