Question

Estimate the mean absolute error from the following data.
20.17, 21.23, 20.79, 22.07, 21.78

Options

• 0.85

• 0.58

• 0.03

• 0.01

Answer 1

0.58

Explanation: 

\[\mathrm{a_m}=\frac{20.17+21.23+20.79+22.07+21.78}{5}\]
\[\mathbf{a}_{\mathrm{m}}=21.21\]
\[\mid\Delta\mathrm{a}_1\mid=\mid21.21-20.17\mid=1.04\]
\[|\Delta\mathfrak{a}_2|=|21.21-21.23|=0.02\]
\[\mid\Delta\mathfrak{a}_3\mid=0.42\]
\[\mid\Delta\mathrm{а}_4\mid=0.86\]
\[\mid\Delta\mathrm{а}_5\mid=0.57\]
\[|\Delta\mathrm{a}_\mathrm{m}|=\frac{|\Delta\mathrm{a}_1|+|\Delta\mathrm{a}_2|+|\Delta\mathrm{a}_3|+|\Delta\mathrm{a}_4|+|\Delta\mathrm{a}_5|}{5}\]
\[=\frac{1.04+0.02+0.42+0.86+0.57}{5}=0.58\]