How to use the elective exam scaled score comparison
Two students with the same raw score can end up with different scaled scores, because each elective exam is scored against its own cohort and every cohort has its own mean and spread. Working out how large that gap actually is by hand is tedious. Enter the name, raw score, cohort mean and cohort standard deviation for each of the two exams, together with the scale centre and step from whatever reference you are using.
The method is straightforward. For each exam the mean is subtracted from your raw score and the result divided by the standard deviation to give a Z score, which is multiplied by the step and added to the centre to give the scaled score. The difference is reported as the first exam minus the second, and the formula actually used is printed in the result so you can see which centre and step went into it. The table lists the raw score, mean, deviation, Z score and scaled score for both exams.
This page does not decide which elective is the better bet. The scaled-score gap can be worked out, but whether it helps you depends on the cohort that year and on how each college converts and weights the result. Percentile ranks, letter bands and college-specific weighting are not supported.
Frequently Asked Questions
No. It uses the mean and standard deviation you enter to report the difference in scaled scores and nothing else. Which elective works out better depends on who sits it that year and on how each college treats the result.
The centre and step of a scaled score formula differ between exam sections and can be revised. This page embeds no particular set of values and works only inside the figures you supply from your own reference.
The difference reads as 0.0 pts and the higher-score row says the two are equal. A signed zero is never displayed.