title: Efficiency (disambiguation)
text: # Efficiency (disambiguation)
  
  Efficiency is the extent to which time or effort is well used for the intended task or purpose.
  
  Efficiency may also refer to:
  
  * Efficiency (aerodynamics), the amount of lift divided by the aerodynamic drag
  * Efficiency (apartment), a one-room apartment
  * Efficiency (basketball), a statistical benchmark to compare the overall value of players
  * Efficiency (economics), a situation in which nothing can be improved without something else being hurt
     * Efficiency (fair division), any changes made to assist one person would harm another
  * Efficiency (finance), non-mean-variance portfolio analysis, a way of showing that a portfolio is not efficient
  * Efficiency (mechanical)
  * Efficiency (network science), a measure of how efficiently a network exchanges information
  * Efficiency (statistics), a measure of quality of an estimator, experiment, or test
  * Energy efficiency (physics), the ratio of power consumed to useful power output
  