Q 01/05

Which 18th-century German scholar gave the field its name, Statistik?

A) Gottfried Achenwall

B) Gottfried Leibniz

C) Christian Wolff

D) Johann Süssmilch

Answer · why

A) Gottfried Achenwall

Gottfried Achenwall, a Göttingen professor, used the word Statistik in 1749 for the systematic description of a state's affairs, and the name stuck as...

Q 02/05

Which measure of central tendency is the middle value when data are sorted?

A) The mean

B) The median

C) The mode

D) The range

Answer · why

B) The median

The median is the middle value of sorted data; it resists distortion by a few huge values, which is why median income describes a typical household be...

Q 03/05

What is the 'mode' of a data set?

A) The largest value

B) The average value

C) The value that appears most often

D) The smallest value

Answer · why

C) The value that appears most often

The value that appears most often is the mode; a data set can have two modes (bimodal) or none at all if every value occurs just once.

Q 04/05

Which Greek letter is conventionally used for standard deviation?

A) Alpha (α)

B) Mu (μ)

C) Pi (π)

D) Sigma (σ)

Answer · why

D) Sigma (σ)

Sigma (σ) denotes the population standard deviation; a low sigma means data cluster tightly around the mean, while a high sigma means they are spread ...

Q 05/05

In a normal distribution, roughly what percentage of values fall within one standard deviation?

A) 68%

B) 78%

C) 88%

D) 98%

Answer · why

A) 68%

68%: about 68% of values in a normal distribution lie within one standard deviation of the mean, and about 99.7% lie within three.