Things You'll Need
Pen or pencil
Calculate example sets of scores to test the formula. Check to see the highest possible score is high enough; no one should be able to score above. Check the scores on the performers that best fit your statements to make sure the numbers are right. If necessary, calibrate your scale numbers.
Converting raw scores to scaled scores you can use to assess performance over time demands only a modest amount of time and patient work. With enough thoughtful consideration in developing the scale, you can calculate the scores readily. Designing a scale is a matter of knowing how to set performance marks and assigning numbers to these marks.
Scale Score Calculation Directions
Make a set of statements on performance that represent the performance range you believe is right. A simple range includes: an acceptable mark, a low mark, a standard mark, a noteworthy performance and the highest possible achievement. With the statements, define the performances that tell you the typical achievement at a place in your range. If you prefer a finer scale, write six to 25 statements.
Develop statements that work for all performance results you want to use your scale for.
Assign numbers from a chosen range to each statement. Begin with the standard. This number represents the standard performance by a person, the achievement that other performances are measured by. The number 100 is a normal standard. Put a zero in your scale, at the bottom—this is the lowest possible score.
Chose the highest number you believe can be achieved, the perfect score. Place this number--200, for example--at the top with an assignment to the best statement. Then, assign a number to the acceptable mark that places the statement the right numerical distance from the standard statement and the zero. Next, number the low score to place its statement just right, in between the acceptable statement and the standard. Last, number the statement on noteworthy performance to place it your chosen measure above the standard statement, yet less than the perfect.
Design your formula. Equate the scaled score to the raw score times the division of the performance score by the standard.
For each performance score, use the equation to calculate the scaled score.
Arrange the scaled scores in order from highest to lowest. Note the standard, acceptable and perfect score on the chart. Take a look at your scaled scores on the chart to judge your performers.