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**Red: Percent scale Purple: Natural log scale**
**Green: Square root scale Blue: Cube root scale**
**Orange: The Great Grading Scale (the average of the four scales)**
**y = { x + 1.442ln(x + 1) + x^.5 + x^(1/3) }/ 4, x is a percent.**
**TGGS has been revised to include formulas from the family, y = x^s, where x is a % score and 0 < s < **=** 1. Therefore, the graphs are easier to grasp than originally displayed; in this case, s = 1, .8, .65, .5, .35, & .2, a nicely patterned set of values that offers flexible and reasonable options. These formulas are similar to the data transformations that are used by researchers as denoted by Huck, Cormier, and Bounds(1974),67, and confirmed by Field(2005),80.**
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