Q.Explain the meaning of the term 'statistics' in its plural and singular senses, giving one standard definition of each.

The single word 'statistics' is used in two different grammatical senses, and a good answer must distinguish the data-sense from the science-sense.

In the plural sense statistics means the numerical facts themselves, while in the singular sense it means the science of collecting, presenting, analysing and interpreting those facts.

The word statistics is used in two distinct senses.

1. Plural sense — statistics as data. Here 'statistics' means the numerical facts collected about a subject: sales figures, population counts, rainfall figures, prices. The standard definition is Horace Secrist's: statistics are aggregates of facts, affected to a marked extent by multiplicity of causes, numerically expressed, enumerated or estimated according to reasonable standards of accuracy, collected in a systematic manner for a predetermined purpose and placed in relation to each other. Every phrase of this definition is really a characteristic of statistical data (see the characteristics question).

2. Singular sense — statistics as a science/method. Here 'statistics' means the discipline that handles such data. The standard definition is Croxton and Cowden's: statistics is the science which deals with the collection, presentation, analysis and interpretation of numerical data. Used this way the word takes a singular verb ('statistics is...').

The two senses are complementary: the singular-sense science is the method by which the plural-sense data is made useful. Keeping them apart avoids confusion when the same word appears in a sentence such as 'statistics (the science) is used to analyse the statistics (the data) of unemployment.'

A common error is giving only one definition and treating 'statistics' as having a single meaning. Another is quoting a definition without stating which sense (plural or singular) it belongs to — Secrist's definition describes the data (plural), Croxton and Cowden's describes the science (singular).