Performance of Readability Formulas under Conditions of Restricted Ability Level and Restricted Difficulty of Materials,,
Rodriguez T. Nelson, Lee H. Hansen · The Journal of Experimental Education · 1975
Readability formulas are designed to provide quantitative estimates of the relative difficulty of pieces of writing. Formulas developed to date have been designed to be used across materials of varying difficulty and with subjects of varying ability and maturity. This study explored the extent to which an increase in the accuracy of a specific readability formula could be obtained by norming it for a restricted set of reading materials and subjects. Using the earlier work of Bormuth, the authors constructed readability formulas from doze data gathered on textbook, newspaper, and leisure reading passages administered to seventh graders. Generally, it was found that narrow-band formulas designed for material of restricted difficulty and subjects with a narrower range of ability offered somewhat more accuracy than more general formulas.