摘要：Reliability and validity are very often misunderstood. Tests or measurement instruments are not reliable and valid. Because, reliability is a characteristic of scores, as for validity is a property of interpretations and uses of scores. Reliability and validity are population or sample or group dependent concepts. As for reliability coefficients, validity coefficients fluctuate from population to population, from sample to sample as well
关键词：Score reliability; validity; paradigm; scientific revolution; Turkish education and science
