Two tests showing the degree to which their score distributions share common variance is described by what term?

Two tests showing the degree to which their score distributions share common variance is described by what term?

• A. Shared Variance
• B. Reliability
• C. Validity
• D. Internal Consistency

Answer: (A)

Shared variance describes how much of the variance in two tests is overlapping—the part of each test’s score variance that is common to the other. When two tests are related, their scores tend to move together, and the extent of that shared variance is captured by the correlation between the tests and, specifically, the proportion of variance explained, which is r^2. This focuses on how much of one test’s variability is accounted for by the other, not on whether a single test is reliable, valid, or internally consistent. Reliability concerns consistency of measurement, validity concerns whether the test measures what it should, and internal consistency looks at how well items on one test hang together. So, describing the overlap between the tests’ score distributions as shared variance is the most direct way to express their joint variance.

Shared variance describes how much of the variance in two tests is overlapping—the part of each test’s score variance that is common to the other. When two tests are related, their scores tend to move together, and the extent of that shared variance is captured by the correlation between the tests and, specifically, the proportion of variance explained, which is r^2. This focuses on how much of one test’s variability is accounted for by the other, not on whether a single test is reliable, valid, or internally consistent. Reliability concerns consistency of measurement, validity concerns whether the test measures what it should, and internal consistency looks at how well items on one test hang together. So, describing the overlap between the tests’ score distributions as shared variance is the most direct way to express their joint variance.