The total number of measurements of an object that have been made (real).		References in this course: M1L2T2, p. 1/32
The Sample Standard Deviation mathematically describes the scatter of each measurement from the mean of a given data set and is the square root of the variance.		References in this course: M1L2T2, p. 10/32
The sample variance is roughly (or almost) the average of the squared deviations between each of the observations in a set of data from the mean. It is less useful than other descriptors of variability because it represents squared units.		References in this course: M1L2T2, p. 10/32
Sensitivity refers to the deflection of the indicating element when a known weight is placed on the balance pan. 		References in this course: M2L3T1, p. 6/15
A sensitivity weight is a small mass standard with a calibrated mass value and uncertainty that is used to define the mass units per divisions on a balance.		References in this course: M2L4T2, p. 1/20
When you report corrections to weights and the uncertainty, the uncertainty should be reported to two significant figures and the mass correction should be reported to the last significant figure affected by the uncertainty, that is, the same level of significance.		References in this course: M1L4T3, p. 2/17
Stabilization time is the time it takes for the display to become sufficiently constant. Balance stabilization has been sufficiently achieved when the display (readout) becomes constant.		References in this course: M2L3T1, p. 6/15
Check standards (or control standards) are used as part of a process measurement assurance program to provide a "check" on the process and standards to ensure that the standards, measurement results, and measurement processes are within acceptable statistical limits (Handbook 143).		References in this course: M1L3T1, p. 10/29; M2L1T1, p. 8/13
Reference standards are generally of the highest metrological quality available at a given location, from which measurements made at that location are derived (HB 143, HB 150, VIM 6.6).		References in this course: M2L1T1, p. 8/13
Working standards are usually calibrated against a reference standard, and are used routinely to calibrate or check material measures, measuring instruments, or reference materials (HB 143, HB 150, VIM 6.7).		References in this course: M2L1T1, p. 8/13
Surveillance testing is the calibration of your reference standards or working standards between official calibrations to provide additional assurance that all mass values continue to be stable.  It provides an intermediate verification of the mass values for your standards.		References in this course: M1L3T1, P. 23/29




