Contents

134 PART II: Descriptive MethodsKEY CONCEPTSexternal validity 94time sampling 94situation sampling 96naturalistic observation 97participant observation 100reactivity 100structured observation 103field experiment 105unobtrusive measures 107physical traces 107archival records 110selective deposit 111selective survival 112narrative records 113measurement scales 115data reduction 120coding 120content analysis 120interobserver reliability 124correlation coefficient 125demand characteristics 127observer bias 131REVIEW QUESTIONS1 Describe the types of sampling researchers use in observational studies and what theproper use of sampling is intended to accomplish.2 Explain the difference between direct and indirect observational methods andhow the degree of intervention can be used to distinguish direct observationalmethods.3 Describe a research situation in which naturalistic observation can be useful whenethical considerations prevent researchers from intervening to study behavior.4 Explain why reactivity is a problem in observational studies.5 Explain how structured observation represents a “middle ground” in psychologicalresearch and identify the primary advantage and potential cost of this compromise.6 Explain why physical traces and archival data are attractive alternatives to directobservation.7 Describe the different types of physical-trace measures available to psychologistsand the ways in which these measures may be biased.8 Explain how archival data may be used to test the effect of a natural treatment.9 Explain how selective deposit, selective survival, and spurious relationships maybias the interpretation of archival records.10 Describe how data reduction and coding are used in qualitative analyses of narrativerecords and archival data.11 Give an example using each of the four measurement scales to describe how a researchercould measure eye contact between pairs of people in conversation witheach other.12 What are the most common descriptive measures (a) when events are measured on anominal scale, (b) when items are ranked using an ordinal scale, and (c) when behavioris recorded on at least an interval scale.13 Describe the procedures researchers can use to increase interobserver reliability.14 Identify the measurement scales that require a correlation coefficient to assess interobserverreliability, and explain what a negative correlation would indicate in thissituation.15 Explain whether high interobserver reliability ensures that the observations are accurateand valid.16 Describe two ways in which observer bias (expectancy effects) can occur in psychologicalresearch.17 Explain how researchers may reduce observer bias.