How to find the range of a raw score?

Answer 1

First, you probably need more than one raw score. If you only have one raw score then your range is one point, the (score - 1/2) to the (score + 1/2). For a score of 80, the range would be from 79.5 to 80.5. It is kind of meaningless if you find a range for just one score. You need a larger sample size. A better question is: "How do I find the range of a sample of raw scores?" You need all of the raw scores in your sample, not just one score. Because each whole number (i.e., 80) represents a continuum (e.g., of ability), the range goes from 1/2 a point below the lowest score to 1/2 a point above the highest score. Let's look at some fake data with 5 participants: 10 20 30 40 50. The highest score is 50. The lowest score is 10. The range is (10-.5) to (50+.5). The range of raw scores is 9.5 to 50.5, a range of 41 points. If you are looking for the easy answer, then the range is 10 to 50 (lowest score to highest score; a range of 40 points). If you for some reason only have one score (e.g., 80), the long answer is 79.5 to 80.5 (range of one), the short answer is that there is no variability (range of zero).