A researcher develops a brief questionnaire measure of people's level of optimism.To determine whether his measure is a good one,he asks a sample of people to complete his questionnaire twice,separated by one month.At the second session,he also asks his participants to complete another measure of optimism-one that has been an accepted measure of optimism for many years.Using this procedure,the researcher is establishing the
A) independent variable of optimism.
B) precision and accuracy of his measure.
C) reliability and validity of his measure.
D) nomothetic and idiographic features of optimism.

Question

Quizplus · Accepted Answer

By having participants complete the researcher's measure twice and also completing an accepted measure of optimism, the researcher is assessing the reliability and validity of his measure. Reliability refers to the consistency or stability of the measure over time, and by having participants complete the measure twice, the researcher can assess its consistency. Validity refers to whether a measure is actually measuring what it is intended to measure, and by comparing the researcher's measure to an accepted measure of optimism, the researcher can assess the validity of his measure.

A Researcher Develops a Brief Questionnaire Measure of People's Level