What would be the probability of a person chosen at random from the population scoring more than 1.0 standard deviation above or below the mean?
Test-retest reliability coefficients (Pearson Product-Moment Correlations) were calculated based on sample retesting of 50-75 students in Grades K, 1, 3, 5, 8, and 12. The resultant reliability coefficients ranged from (.42) in kindergarten for Spelling to (.94) in the third grade for Reading Recognition. The total median reliability coefficient was (.78). In terms of median coefficient values the greatest confidence in stability is in the total test (.89) and Reading Recognition (.89) and least in Reading Comprehension(.64) and Spelling(.65).