What is 2 standard deviations below the mean?
What is 2 standard deviations below the mean? A score that is two Standard Deviations above the Mean is at or close to the 98th percentile (PR = 98). A score that is two Standard Deviations below the Mean is at or close to the 2nd percentile (PR =2). On most psychological and educational tests, the mean is 100 and the Standard Deviation is 15 points. What is 2 standard deviation on a normal curve? For an approximately normal data set, the values within one standard deviation of the mean account for about 68% of the set; while within two...