Contents

126 PART II: Descriptive Methodstime spent watching television and scores on academic tests are negativelycorrelated. When assessing interobserver reliability, researchers seek positivecorrelations.The strength of a correlation refers to the degree of covariation present.Correlations range in size from 1.00 (a perfect negative relationship) to 1.00(a perfect positive relationship). A value of 0.0 indicates there is no relationshipbetween the two variables. The closer a correlation coefficient is to 1.0or 1.0, the stronger the relationship between the two variables. Note thatthe sign of a correlation signifies only its direction; a correlation coefficientof .46 indicates a stronger relationship than one that is .20. We suggest thatmeasures of interobserver reliability that exceed .85 indicate good agreementbetween observers (but the higher, the better!).In Chapter 5 we discuss the use of correlations for making predictions. Inaddition, Chapter 11 provides a detailed discussion of correlations, includinghow relationships between two variables can be described graphicallyusing scatterplots, how Pearson Product-Moment Correlation Coefficientsare computed, and how these correlations are best interpreted. If you wantto become more familiar with the topic of correlation, refer to Chapter 11.THINKING CRITICALLY ABOUT OBSERVATIONAL RESEARCHA good observational study involves choosing how to sample behavior andevents to observe, selecting the appropriate observational method, and decidinghow to record and analyze observational data. Now that you knowthe basics of observational methods, you also need to know about potentialproblems that can occur. The first problem is associated with the influence ofthe observer on behavior; a second problem occurs when observers’ biasesinfluence what behavior they choose to record. We’ll consider each of theseproblems in turn.Influence of the Observer• The problem of reactivity occurs when the observer influences the behaviorbeing observed.• Research participants may respond to demand characteristics in theresearch situation to guide their behavior.• Methods to control reactivity include concealing the observer’s presence,adaptation (habituation, desensitization), and indirect observation (physicaltraces, archival records).• Researchers must consider ethical issues when attempting to controlreactivity.Reactivity The presence of an observer can lead people to change their behaviorbecause they know they are being observed. We first addressed this issueof reactivity in the section describing participant observation. When individuals“react” to the presence of an observer, their behavior may not represent