Reference no: EM133453803

According to classical test theory, test reliability is based on the notion that test score reliability comprises two parts: true scores and error. A true score is an expected score on a test over an infinite number of testing instances; it is a theoretical idea that can never be known for sure. Errors are inaccuracies that make actual (observed) test scores differ from true scores.

There are several different ways to measure a test's reliability. Test-retest reliability looks at the correlation between original test administrations and retests. The span of time between the two administrations should be less that the time for the true scores to vary. Test-retest reliability looks at error due to time.

Alternate-form reliability looks at the correlation between two different versions of a test. Split-half reliability is similar to alternative-form reliability, splitting a single test into two halves, usually odd and even items, and correlating scores on the two halves. Cronbach's coefficient alpha is also similar, essentially providing the average of all possible split-half reliabilities. Alternate-form, split-half, and Cronbach's coefficient alpha all look at error due to content sampling.

For this Discussion, pretend that you have been contracted to come up with a test to assess intelligence. Think about factors you might consider and steps you might take to ensure the reliability of this test.

Description of factors you might consider and steps you might take to ensure reliability of the intelligence test. Explain why these factors and steps are important.