Enter the standard deviation and the desired confidence level into the calculator to determine the coverage factor. The coverage factor is a multiplier used in uncertainty analysis to establish an interval around a measurement result.
Coverage Factor Formula
The following formula is used to calculate the coverage factor.
k = Z * σ
Variables:
- k is the coverage factor
- Z is the Z-score corresponding to the desired confidence level
- σ is the standard deviation of the measurement process
To calculate the coverage factor, multiply the Z-score corresponding to the desired confidence level by the standard deviation of the measurement process.
What is a Coverage Factor?
The coverage factor, denoted as k, is a numerical factor used in measurement uncertainty analysis. It is applied to the standard deviation to obtain an expanded uncertainty that defines an interval around the measurement result. This interval is expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurand, given the observed data. The coverage factor is related to the confidence level, which is the probability that the true value lies within the interval.
How to Calculate Coverage Factor?
The following steps outline how to calculate the Coverage Factor.
- First, determine the standard deviation (σ) of the measurement process.
- Next, determine the desired confidence level (%) for the interval.
- Next, find the Z-score (Z) that corresponds to the desired confidence level.
- Finally, calculate the Coverage Factor (k) using the formula k = Z * σ.
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
Standard Deviation (σ) = 1.5
Confidence Level (%) = 95
Note: The Z-score for a 95% confidence level is approximately 1.96.
