Validity is .a. concerned with the relationships of random error with systematic error. b. equal to the true score plus the systematic error. c. equal to the true score plus systematic error minus random error. d. concerned with the extent to which differences in scores reflect true differences in the characteristic. e. concerned with the extent to which differences in scores reflect instability in the measurements.

the correct answer is option d.

Explanation:

Validity is concerned with the extent to which differences in scores reflect true differences in the characteristic.

d. concerned with the extent to which differences in scores reflect true differences in the characteristic.

Explanation:

Validity is the level of accuracy of a measurement under research or test. A measurement is said to be valid if its result is closely related to real world values. Validity in research shows how sound one's research is. In data it means getting a true representation of the data a researcher is claiming to measure. To measure validity, the measurement must have internal consistency and good test-retest reliability.

Types of validity.

Validity can be content, construct, face and criterion.

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