Internal and External Validity Quiz

Threats to Validity

• History, maturation, testing, and instrumentation are threats to internal validity.
• Selection, mortality, and extraneous variables are threats to external validity.

Reliability Measures

• Cronbach's alpha measures the internal consistency of a test or scale.
• Higher values of Cronbach's alpha indicate higher reliability.
• KR-20 assesses the reliability of a test with dichotomous response categories.

Types of Validity

• External validity concerns whether the results can be generalized to other populations and settings.
• Content validity involves ensuring that a test measures the intended construct, e.g., a mathematics test should include relevant mathematical concepts.
• Face validity assesses whether a test appears to measure what it claims to measure.
• Construct validity assesses whether a measurement reflects the entire range of the construct being measured.
• Concurrent validity compares the accuracy of a data collection instrument with a criterion measure at the same time.
• Predictive validity measures how well a test predicts a future outcome or criterion.

Validity and Theory

• Construct validity involves relating an instrument for data collection to a theoretical framework and usually involves hypothesis testing.
• It indicates how well the scale measures the construct it was designed to measure and attempts to validate a body of theory underlying the measurement and testing of the hypothesized relationships.