Economies of scale (EOS)

The reduction in costs of producing an extra unit of output. Usually related to the minimum efficient level of output at which a firm can produce efficiently relative to market size.

Effective demand

The desire to buy together with the ability pay for as good or service. Those who have a desire to buy but cannot pay the price or cost are said to have limited or no effective demand.

Effective exchange rate (EER)

The actual rate at which one unit of foreign currency is exchanged for local currency.

Elastic demand

A commodity for which the percentage changes in demand is proportionately greater than the percentage change in price. For example, a one percent change in the price of the good or service leads to a greater than one percent change in the quantity demanded.

Elastic supply

A commodity for which the percentage changes in supply is proportionately greater than the percentage change in price. For example, a one percent change in the price of the good or service leads to a greater than one percent change in the quantity supplied.

Elasticity

Measure of a percentage change of one thing relative to a percentage change in another. For example, the price elasticity of demand is the percentage change in quantity demanded relative to the percentage change in the price.

Elasticity of demand

The percentage change in quantity demanded relative to the percentage change in the price.

• Own price elasticity: When the change in quantity demanded is related to the price of the commodity.

• Cross price elasticity: When the change in quantity demanded is related to the price of another commodity.

Elasticity of supply

The percentage change in the quantity supplied relative to a percentage change in the price of a commodity.

Emergency

IPC phase 4. Households either:

Have large food consumption gaps which are reflected in very high acute malnutrition and excess mortality.

OR

Are able to mitigate large food consumption gaps but only by employing emergency livelihood strategies and asset liquidation.

See International Phase Classification (IPC).

Ensemble forecast

An ensemble forecast is either a collection of model runs (using the same model) started from slightly different initial conditions, or a collection of model runs using different models. This tests the strength of forecasts; if ensembles give similar results (a convergence of evidence), then we have confidence in the forecast.

Equity

A situation in which resources are relatively distributed to all members of society.

Exchange efficiency

A situation in which all benefits from trade have been exhausted and it is not possible to do further exchange without reducing the happiness of another agent.

Exchange rate

The rate at which one currency can be exchanged for another.

Exchange terms

The terms under which goods and services are exchanged in transaction.

Exclusionary pricing

Also, Predatory pricing

Occurs when one firm lowers and maintains its price below costs until other efficient firms exit the market. Predatory ricing eliminates competition (results into monopoly power).

Expectations

What a market actor believes will occur at some point in the future, and that time frame is usually defined. For example, the price a seller believes they will receive three months in the future.

Expenditure shares

The portion of a household’s expenditures allocated to a particular good, service or group of goods and services. This is essentially the same as budget shares.

Export parity price (XPP)

The monetary value of a product sold at a specific location in a foreign country, but valued from a specific location in the exporting country.