standard scores
Message posted by Holly (via 66.66.35.113) on September 19, 2001 at 11:20 PM (ET)

A simple question, but apparently I am having a brain freeze. I have a set of raw scores that I would like to convert to standard scores (similar to IQ scores; a mean of 100 and SD of 10... I am not interested in converting these to z scores). I know the raw scores and the means and standard deviations of the raw scores. How do I make this conversion? Is setting up a proportion a valid way to do this (i.e., raw score/raw mean = standard score/standard mean)?
Thanks...

READERS RESPOND:
(In chronological order. Most recent at the bottom.)

Re: standard scores
Message posted by Tomi (via 154.32.143.51) on September 21, 2001 at 2:41 AM (ET)

Original mean: m1
Original sd: s1

Final mean: m2 (in your case you want 100)
Final sd: s2

Original value: x1
Final value: x2

Formula: ((x1-m1)*s2/s1)+m2

Re: standard scores
Message posted by Tomi (via 154.32.143.51) on September 21, 2001 at 2:46 AM (ET)

I meant:

Formula: x2=((x1-m1)*s2/s1)+m2

--------------
Based on:

z=(x1-m1)/s1

x2=z*s2+m2

Therefore x2=((x1-m1)/s1)*s2+m2= what I put above.

Re: standard scores
Message posted by Holly (via 66.66.35.113) on October 5, 2001 at 11:55 PM (ET)