In a data set, the difference between the highest and lowest observed values is known...

In a data set, thedifference between the highest and lowest observed values is known as the range. The range is a measure of dispersion that indicates the spread of the data. It is calculated by subtracting the smallest value in the data set from the largest value. The range gives a quick sense of the variability in the data but does not provide information about the distribution of values between the extremes.

Percentile (A): A percentile indicates the value below which a given percentage of observations in a data set falls.

Standard deviation (B): Standard deviation measures the average amount by which each data point differs from the mean, indicating the spread of the data around the mean.

Quartile deviation (D): Quartile deviation, or semi-interquartile range, measures the spread of the middle 50% of data, providing an understanding of variability around the median.

References

NAHQ Body of Knowledge: Data Measurement and Analysis

NAHQ CPHQ Exam Preparation Materials: Understanding Measures of Dispersion

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