Final answer:
A psychometric test that gives the same score each time it is taken is called reliable. Reliability is crucial for ensuring a test consistently measures what it is supposed to, over time. The reliability of a test is bolstered by methods like norming and standardization.
Step-by-step explanation:
If a psychometric test gives approximately the same score each time a person takes it, it is called reliable. Reliability refers to the consistency of a measure, meaning that the test is able to produce the same results under consistent conditions. This concept is critical in psychometrics to ensure that a test is accurately measuring what it is intended to measure over time. In addition to reliability, precision is also an essential quality, which indicates how closely a measurement matches the same measurement when repeated. Precision and reliability are interconnected, with precision being a component of a test's reliability. A reliable test can help in comparing results across different time periods, as shown with reliability scales used in instruments like the MMPI-2-RF.
Norming and standardization are methods used to ensure a test's reliability and involve administering the test to a large population to collect data that helps interpret future scores and establish norms. An example of a standardized and normed test that is known for its reliability across time is the Stanford-Binet Intelligence Scale.
Similarly, the scientific method emphasizes repetition to validate the results of experiments, showing that the more often an experiment is repeated with the same results, the more reliable those results are considered to be. Likewise, confidence intervals use repeatability to ensure that a percentage of the generated intervals will contain the true population mean, further highlighting the importance of reliability and precision in research and testing.