In the U.S., doctors usually get suspicious when a PSA level is 4.0 ng/mL. But studies show that many men with levels well above 4.0 ng/mL do not have cancer. And many men with prostate cancer have PSA scores well below this level. There are a lot of ways to tweak the PSA test to try to get better results.
The Standard Deviation Formula. In this formula, x is the value of the mean, N is the sample size, and x i represents each data value from i=1 to i=N.. The â symbol indicates that you must add up the sum. (x 1 - x) 2 + (x 2 - x) 2 + (x 3 - x) 2 + (x 4 - x) 2 + (x 5 - x) 2. . . + (x N-x) 2.
The standard deviation of the frequency distribution table is 19.76797544.Use the following formula to find Variance. Variance = s 2 Therefore, the variance is the answer on the previous screen before you took the square root of the answer.The variance of the frequency distribution table is 390.7728532.he standard deviation of the frequency distribution table is 19.76797544.Use the following formula to find Variance. Variance = s 2 Therefore, the variance is the answer on the previous screen before you took the square root of the answer.The variance of the frequency distribution table is 390.7728532.