cognitive fun! talk RSS http://cognitivefun.net Cognitive neuroscience for everyone! Sat, 04 Feb 2012 04:39:06 -0800 If your score is colored green, then it is better (than the mean); if it is red, then it is worse (than the mean). Some tests are reverse scored, but the coloration is there to make it even more... obvious. Mon, 29 Mar 2010 09:36:09 -0700 http://cognitivefun.net/talk/post/18862#r_19492 I think the proper way to interpret it is to say that if you z-score is -2, you are scoring 2 standard deviations below the mean. If we are talking about a test like a time test--where lower is better--that is a very good thing. Mon, 29 Mar 2010 12:02:19 -0700 http://cognitivefun.net/talk/post/18862#r_19487 Here's a calculator you can play with so that you can understand how it works: http://www.danielsoper.com/statcalc/calc22.aspx Here's an answer that Dr. Math provided for the same question: http://mathforum.org/library/drmath/view/68384.html You don't need to study statistics. It's really very simple mathematics. Sun, 28 Feb 2010 09:45:00 -0800 http://cognitivefun.net/talk/post/18862#r_18867 I could be wrong but with reaction time based tests mental power/efficacy is inversely related to time so faster time = below the mean (-z score) but above average ability. I think... Sun, 28 Feb 2010 08:28:29 -0800 http://cognitivefun.net/talk/post/18862#r_18866 e.g., on Stroop colors test, I show app. 44% above the refernce, yet have a negative 0.2 z score. That seems to mean I'm below hte mean by ).2 standard deviations, no? and, what's the standard deviation for this sub population? 16? Thanks for help/patience; i did not study statistics Sun, 28 Feb 2010 07:40:59 -0800 http://cognitivefun.net/talk/post/18862#r_18864 I've reviewed some of the posts here and the links to the statistics sites describing Z scores but I remain confused, so pardon my revisiting this issue. I have several scores that are shown as very substantially above the "reference." I thought the "reference" was the arithmetic mean for the CF site. Yet, I have received negative Z scores, which seem to indicate that I'm below the mean. Wassup? Sun, 28 Feb 2010 07:21:49 -0800 http://cognitivefun.net/talk/post/18862#r_18863 Confused about Z Scores, etc. Sun, 28 Feb 2010 07:21:49 -0800 http://cognitivefun.net/talk/post/18862#r_18862