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.
'Residual' is the difference between the first two above (Y-Y^). 'Std Error Residual' is the standard deviation of the 'Residual' statistic. Used like other standard errors.'Student Residual' is the standardized residual. Calculated as 'Residual' / 'Std Error Residual'.tandard Error of the Residuals. Hello, Iknow that the standard error of the residuals of a regression equation is given as the sqare root of SSE divided by the degrees of freedom and its interpretation is that it is the average deviation of each value of Y around around the estimated Y values from the line.