Noun

(-)

The property of being effective, of achieving results.

The effectiveness of the drug was well established.

The capacity or potential for achieving results.

*

The degree to which something achieves results.

He questioned the effectiveness of the treatment.

* 2013 , Phil McNulty, "[http://www.bbc.co.uk/sport/0/football/23830980]", BBC Sport , 1 September 2013:

United were having more possession but a sign of the effectiveness of Liverpool's defence was that it took the visitors 76 minutes to force Mignolet into serious action, when he dived to punch away a shot from substitute Nani.

Noun

(wikipedia simplicity)

The quality or state of being simple, unmixed, or uncompounded; as, the simplicity of metals or of earths.

The quality or state of being not complex, or of consisting of few parts; as, the simplicity of a machine.

Artlessness of mind; freedom from cunning or duplicity; lack of acuteness and sagacity.

Freedom from artificial ornament, pretentious style, or luxury; plainness; as, simplicity of dress, of style, or of language; simplicity of diet; simplicity of life.

Freedom from subtlety or abstruseness; clearness; as, the simplicity of a doctrine; the simplicity of an explanation or a demonstration.

Freedom from complication; efficiency.

*{{quote-magazine, date=2013-08-03, volume=408, issue=8847, magazine=(The Economist)

, title= Boundary problems , passage=Economics is a messy discipline: too fluid to be a science, too rigorous to be an art. Perhaps it is fitting that economists’ most-used metric, gross domestic product (GDP), is a tangle too. GDP measures the total value of output in an economic territory. Its apparent simplicity explains why it is scrutinised down to tenths of a percentage point every month.}}

Weakness of intellect; silliness; folly.

(rare) An act or instance of foolishness.

*, II.31:

*:speaking of the great simplicity we commit, in leaving yong children under the government and charge of their fathers and parents.