validity and reliability

Content Validity – The test covers all aspects of the concept it is supposed to measure. For example, an intelligence test should assess a wide range of cognitive abilities, not just memory or verbal skills.

Predictive Validity (Criterion-Related Validity) – The test accurately predicts future performance on related tasks. For example, if an intelligence test predicts academic success (e.g., high IQ scores correlate with high grades), it has strong predictive validity.

Construct Validity – The test actually measures the abstract concept of intelligence and not something else. It should align with established theories of intelligence.

Test-Retest Reliability – The same test is given to the same group of people on two different occasions. If the scores are similar both times, the test is considered reliable.

Split-Half Reliability – The test is divided into two halves (e.g., odd vs. even questions), and scores from both halves are compared. A high correlation between the two halves indicates reliability.

Inter-Rater Reliability – Different scorers (raters) evaluate the test, and their scores are compared. If multiple raters give similar scores, the test has high reliability.