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Statistics & five-observation description

Measurement Variability Calculator

Describe exactly five finite measurements using explicit variance and quartile conventions.

182 / MEASUREMENT VARIABILITY

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INPUT GROUP 01

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YOUR CALCULATION

Describe five entered measurements using explicit variance and quartile conventions.

Arithmetic mean

3

Median

3

Sample variance (n − 1)

2.5

Standard deviation

1.581

Maximum minus minimum

4

Interquartile range (median-excluded halves)

3

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Illustrative inputs loaded. Replace them with your own assumptions.

How the measurement variability calculator works

The arithmetic mean divides the sum of five measurements by five. Variance sums squared deviations and divides by four for sample variance or five for population description. Standard deviation is its square root and range is maximum less minimum.

Sort the values for the median. Quartiles are medians of the two-value lower and upper halves after excluding the middle observation; other software can use a different interpolated-quartile convention.

All entries require one common measurement unit. This fixed five-observation description neither establishes process stability nor performs measurement-system repeatability/reproducibility, uncertainty analysis or specification acceptance.

Worked example

Measurements 1, 2, 3, 4 and 5 have mean and median 3, sample variance 2.5, SD about 1.581139, range 4 and median-excluded-halves IQR 3. Changing the final value to 10 makes the mean 4.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

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