What is TGGS?
Sick of grades??
Grade on a curve
15 Point TGGS
20 Point TGGS
24 Point TGGS
100 Point TGGS
TGGS Graphs
TGGS logo
TGGS Poster

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.