Awareness of sources of error unique to structured observations, such as the Hawthorne effect and observer variability in the absence of training, are important to remember when high stakes uses are made with assessment results. Six rules were provided to help us make sound anecdotal records.
To conclude, the chapter recognized three classical examples of instrument design and validation for Paths 2-6. These were Thurstone Scales, Semantic Differential Scales, and Self-concept measures in education.

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