Q 01/05

The word 'statistics' comes from a German word originally meaning the description of what?

A) A state or country

B) A merchant's ledger

C) A star chart or almanac

D) A royal census taker

Answer · why

A) A state or country

Statistik described the affairs of a state; today the field covers collecting, analysing and presenting any data.

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

It resists distortion by a few huge values, which is why median income beats mean income for describing a typical household.

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

In a perfect normal distribution the mode, median and mean all coincide.

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)

A low value means data cluster tightly around the mean; a high value means they are spread out.

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%

The 68-95-99.7 rule extends the idea to two and three times the spread.