The form of standard score
) used in a number of published personality inventory
tests, including the California Psychological Inventory
. This is a lot easier for some people to understand than Z scores
because they don't have decimals
and negative numbers
and we're usually familiar with a scale of 0 to 100, which they have.
In T scores, the mean
50 and the standard deviation
To calculate a T score, you use this formula:
T = 10(Z) + 50
Pretty easy, once you've figured out your Z score. Let's do an example, referring to the set of scores I included in that writeup.. as you can see, the Z score for a noder who'd written 94 writeups was 1.1, so what would their T score be?
Which comes out to 61. As you remember, the mean is always 50 and the standard deviation is always 10, so when you think about it, you can see how 11 above the mean in a scale of 100 would be 1.1 standard deviations.
Note that this, while a range of 100, is not the same as percentile.