Contents

448 Glossarycomparison of two means A statistical technique that can be applied (usually afterobtaining a statistically significant omnibus F-test) to locate the specific source of systematicvariation in an experiment by comparing means two at a time.complex design Experiment in which two or more independent variables are studiedsimultaneously.confidence interval Indicates the range of values which we can expect to contain apopulation value with a specified degree of confidence (e.g., 95%).confidence interval for a population parameter A range of values around a samplestatistic (e.g., sample mean) with specified probability (e.g., .95) that the populationparameter (e.g., population mean) has been captured within that interval.confirming what the data reveal In the third stage of data analysis the researcher determineswhat the data tell us about behavior. Statistical techniques are used to counterarguments that the results are simply “due to chance.”confounding Occurs when the independent variable of interest systematically covarieswith a second, unintended independent variable.construct A concept or idea used in psychological theories to explain behavior or mentalprocesses; examples include aggression, depression, intelligence, memory, andpersonality.contamination Occurs when there is communication of information about the experimentbetween groups of participants.content analysis Any of a variety of techniques for making inferences by objectivelyidentifying specific characteristics of messages, usually written communications butmay be any form of message; used extensively in the analysis of archival data.control Key component of the scientific method whereby the effects of various factorspossibly responsible for a phenomenon are isolated; three basic types of control aremanipulation, holding conditions constant, and balancing.correlation Exists when two different measures of the same people, events, or thingsvary together; the presence of a correlation makes it possible to predict values on onevariable by knowing the values on the second variable.correlation coefficient Statistic indicating how well two measures vary together; absolutesize ranges from 0.0 (no correlation) to 1.00 (perfect correlation); direction ofcovariation is indicated by the sign of the coefficient, a plus () indicating that bothmeasures covary in the same direction and a minus () indicating that the variablesvary in opposite directions.correlational research Research to identify predictive relationships among naturallyoccurring variables.counterbalancing A control technique for distributing (balancing) practice effects acrossthe conditions of a repeated measures design. How counterbalancing is accomplisheddepends on whether a complete or an incomplete repeated measures design is used.cross-sectional design Survey research design in which one or more samples of thepopulation are selected and information is collected from the samples at one time.data reduction Process in the analysis of behavioral data whereby results are meaningfullyorganized and statements summarizing important findings are prepared.debriefing Process following a research session through which participants are informedabout the rationale for the research in which they participated, about the needfor any deception, and about their specific contribution to the research. Importantgoals of debriefing are to clear up any misconceptions and to leave participants witha positive feeling toward psychological research.deception Intentionally withholding information from a participant about significantaspects of a re search project or presenting misinformation about the research toparticipants.