Hand and Foot Modifier FA -F9 and T1 - T9. E1 - E4, FA - F9, TA - T9 Level II Modifier. E1-E4 Anatomic modifiers which are associated with the eyelid. FA, F1- F9 Anatomic modifiers which are associated with the fingers. TA, T1- T9 Anatomic modifiers which are associated with the toes.
X-bar and R Control Chart Issues and Resolution. X-bar and R control charts are used in quality control to identify when special cause or out-of-control conditions occur in time-series data so that timely corrective actions can be taken to resolve problems.
The x-bar is the symbol (or expression) used to represent the sample mean, a statistic, and that mean is used to estimate the true population parameter, mu. To find the average height of professional basketball players (the population), we don't need to measure every player, just some of them (the sample).