Mean Plus Minus Standard Deviation. Again we see that the majority of observations are within one standard deviation of. For the serum triglyceride data s 0 04802 0 22 mmol litre.
In numerical format this is 3 x 0 5064 9 34 10 9. Pr μ 2 σ x μ 2 σ φ 2 φ 2 0 9772 1 0 9772 0 9545 displaystyle pr mu 2 sigma leq x leq mu 2 sigma phi 2 phi 2 approx 0 9772 1 0 9772 approx 0 9545. To compute the probability that an observation is within two standard deviations of the mean small differences due to rounding.
In numerical format this is 3 x 0 5064 9 34 10 9.
Where the mean is bigger than the median the distribution is positively skewed. This means that the distribution used to set the specification limits in six sigma is not the actual mean but the mean plus or minus 1 5 standard deviations. The shaded area covers plus or minus one sd from the mean and includes about two thirds of the values. 1995 2019graphpad software llc.
