Reliability

• 1. Test-Retest Reliability – each one of several people takes the same test twice
• 1.a) If it has correlation it has Temporal Stability.
• 1.a) Longer time interval = lower reliability coefficient
• 1.a) Trait Anxiety – the amount of anxiety an individual has all the time
• 1.a) State Anxiety – the amount of anxiety an individual has at any given moment
• 2. Alternate-Forms Reliability
• 2.a) If the scores of the two forms are similar when correlated, it has form stability.
• 3. Internal Reliability – looking at the consistency with which an applicant responds to items measuring a similar dimension or construct
• 3.a) Longer tests = higher internal consistency
• Item Homogeneity – do all items measures the same thing? Or do they have different constructs?
• 3.a) Split - Half Method – items in the test are split into two groups
• 3.a) Spearman Brown Prophecy – researchers used this formula in Split-Half Method because the number of items are reduced to adjust the correlation
• 3.a) Cronbach’s Coefficient Alpha and K-R 20 – more popular and accurate methods of determining internal reliability
• K-R 20 is used for tests containing dichotomous items
• 4. Scorer Reliability – a test or inventory can have homogeneous items and yield heterogenous scores and still not be reliable if the person scoring the test makes mistakes
• 4.a) Interrater Reliability – when human judgement of performance is involved