Scientific method - an organized way of using experience and testing ideas to expand and
refine knowledge.
Hypothesis -a specific statement about behavior or mental processes that is tested through
research.
Correlation - an association or a relationship among variables, as we might find between
height and weight or between study habits and school grades.
Selection factors -a source of bias that may occur in research findings when participants
are allowed to choose for themselves a certain treatment in a scientific study.
Sample - part of a population.
Population -a complete group of interest to researchers, from which is drawn.
Random sample -a sample drawn so that each member of a population has an equal chance
of being selected to participate.
Stratified sample -a sample drawn so that identified subgroups in the population are
represented proportionately in the sample.
Volunteer bias -a source of bias or error in research reflecting the prospect that people who
offer to participate in research studies differ systematically from people who do not.
Case study -a carefully drawn biography that may be obtained through interviews,
questionnaires, and psychological tests.
Naturalistic observation - a scientific method in which organisms are observed in their
natural environments.
Correlational method- a mathematical method of determining whether one variable increases
or decreases as another variable increases or decreases.
Correlation coefficient - a number between +1.00 and -1.00 that expresses the strength and
direction of the relationship between two variables.
refine knowledge.
Hypothesis -a specific statement about behavior or mental processes that is tested through
research.
Correlation - an association or a relationship among variables, as we might find between
height and weight or between study habits and school grades.
Selection factors -a source of bias that may occur in research findings when participants
are allowed to choose for themselves a certain treatment in a scientific study.
Sample - part of a population.
Population -a complete group of interest to researchers, from which is drawn.
Random sample -a sample drawn so that each member of a population has an equal chance
of being selected to participate.
Stratified sample -a sample drawn so that identified subgroups in the population are
represented proportionately in the sample.
Volunteer bias -a source of bias or error in research reflecting the prospect that people who
offer to participate in research studies differ systematically from people who do not.
Case study -a carefully drawn biography that may be obtained through interviews,
questionnaires, and psychological tests.
Naturalistic observation - a scientific method in which organisms are observed in their
natural environments.
Correlational method- a mathematical method of determining whether one variable increases
or decreases as another variable increases or decreases.
Correlation coefficient - a number between +1.00 and -1.00 that expresses the strength and
direction of the relationship between two variables.
