When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Efficiency - Wikipedia

    en.wikipedia.org/wiki/Efficiency

    Efficiency is very often confused with effectiveness. In general, efficiency is a measurable concept, quantitatively determined by the ratio of useful output to total useful input. Effectiveness is the simpler concept of being able to achieve a desired result, which can be expressed quantitatively but does not usually require more complicated ...

  3. Efficiency (statistics) - Wikipedia

    en.wikipedia.org/wiki/Efficiency_(statistics)

    In statistics, efficiency is a measure of quality of an estimator, of an experimental design, [1] or of a hypothesis testing procedure. [2] Essentially, a more efficient estimator needs fewer input data or observations than a less efficient one to achieve the Cramér–Rao bound.

  4. Engine efficiency - Wikipedia

    en.wikipedia.org/wiki/Engine_efficiency

    Engine efficiency of thermal engines is the relationship between the total energy contained in the fuel, and the amount of energy used to perform useful work. There are two classifications of thermal engines- Internal combustion (gasoline, diesel and gas turbine-Brayton cycle engines) and

  5. Economic efficiency - Wikipedia

    en.wikipedia.org/wiki/Economic_efficiency

    The first fundamental welfare theorem provides some basis for the belief in efficiency of market economies, as it states that any perfectly competitive market equilibrium is Pareto efficient. The assumption of perfect competition means that this result is only valid in the absence of market imperfections , which are significant in real markets.

  6. Pareto efficiency - Wikipedia

    en.wikipedia.org/wiki/Pareto_efficiency

    Fractional Pareto efficiency is a strengthening of Pareto efficiency in the context of fair item allocation. An allocation of indivisible items is fractionally Pareto-efficient (fPE or fPO) if it is not Pareto-dominated even by an allocation in which some items are split between agents. This is in contrast to standard Pareto efficiency, which ...

  7. Energy conversion efficiency - Wikipedia

    en.wikipedia.org/wiki/Energy_conversion_efficiency

    Unlike efficacy (effectiveness), which is a unit of measurement, efficiency is a unitless number expressed as a percentage, requiring only that the input and output units be of the same type. The luminous efficiency of a light source is thus the percentage of luminous efficacy per theoretical maximum efficacy at a specific wavelength.

  8. Energy efficiency in transport - Wikipedia

    en.wikipedia.org/wiki/Energy_efficiency_in_transport

    Because of their light weight and small motors, they are extremely energy-efficient with a typical energy efficiency of 1.1 kWh (4.0 MJ) per 100 km [56] (1904 MPGe 810 km/L 0.124 L/100 km), even more efficient than bicycles and walking. However, as they must be recharged frequently, they are often collected overnight with motor vehicles ...

  9. Electrical efficiency - Wikipedia

    en.wikipedia.org/wiki/Electrical_efficiency

    A premium efficiency electric motor: more than 90% (see Main Article: Premium efficiency). A large power transformer used in the electrical grid may have efficiency of more than 99%. Early 19th century transformers were much less efficient, wasting up to a third of the energy passing through them. [citation needed]