Class 11 Statistics: Measure of Dispersion

Meaning of Dispersion

Meaning of Dispersion — see why the same average can hide two completely different worlds, from the river-crossing story to same-mean companies. GSEB Class 11 Statistics notes with definitions and the six desirable characteristics.

Absolute and Relative Measures

Absolute and Relative Measures — know which dispersion measures carry units and which coefficients free them for comparison. GSEB Class 11 Statistics notes with the measure family tree and paired-coefficient table.

Range

Range — compute the simplest spread in one step and judge it with the coefficient of range. GSEB Class 11 Statistics notes with grouped-class rules, solved sums and the quality-control use.

Quartile Deviation

Quartile Deviation — measure the spread of the middle 50 percent, the only dispersion that survives open-ended classes. GSEB Class 11 Statistics notes with quartile formulas, solved sums and the coefficient rule.

Mean Deviation

Mean Deviation — average the absolute distances from the mean and see why absolute values are unavoidable. GSEB Class 11 Statistics notes with raw and grouped formulas, solved sums and the signed-to-absolute visual.

Standard Deviation

Standard Deviation — square the deviations, average them and take the root: the best measure of spread in statistics. GSEB Class 11 Statistics notes with three computation methods, transform rules, solved sums and a practice lab.

Coefficient of Variation

Coefficient of Variation — compare the consistency of two groups in any unit with the percentage form of standard deviation. GSEB Class 11 Statistics notes with solved comparisons, the means caveat and gauges.

Combined Standard Deviation

Combined Standard Deviation — merge two groups into one spread using the within-plus-between variance decomposition. GSEB Class 11 Statistics notes with the four-step order, formulas and solved sums.