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HOUSEHOLD SECTOR: The basic macroeconomic sector that includes the entire, wants andneedssatisfying population of the economy. The household sector is the eating, breathing, consuming population of the economy. In a word "everyone," all consumers, all people. This sector includes everyone seeking to satisfy unlimited wants and needs. While it's called "household" sector, this doesn't require that you own a house, live in a house, or even know someone has ever seen a house to be included. The term household sector is merely a shortcut used by economists to indicate the consuming, wantsandneedssatisfying population.
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ARC ELASTICITY: The average elasticity for discrete changes in two variables. The distinguishing characteristic of arc elasticity is that percentage changes are calculated based on the average of initial and ending values of each variable, rather than initial values. Arc elasticity is generally calculated using the midpoint elasticity formula. The contrast to arc elasticity is point elasticity. For infinitesimally small changes in two variables, arc elasticity is the same as point elasticity. Arc elasticity is best considered the average elasticity over a range of values for a relation. Like any average, some values within the range are likely to be greater and some less. However, it provides a quick approximation of elasticity when more precise and sophisticated calculation techniques are not possible.Working Through an ExampleA Standard Demand Curve 

 The demand curve displayed to the right can be used to illustrate the measurement of arc elasticity using the midpoint elasticity formula. If the price declines from $12 to $8, the quantity demanded increases from 4 to 6, from point X to point Z. Using this midpoint formula (with price designated as P and quantity designated as Q) average price elasticity of demand is:midpoint elasticity  =  (Q[Z]  Q[X]) (Q[Z] + Q[X])/2  ÷  (P[Z]  P[X]) (P[Z] + P[X])/2 
midpoint elasticity  =  (6  4) (6 + 4)/2  ÷  (8  12) (8 + 12)/2  =  (2) (5)  ÷  (4) (10) 
midpoint elasticity  =  0.4  ÷  0.4  =  1.0 
Ignoring the minus sign, the price elasticity of demand over this segment of the demand curve from X to Z is 1.0.An Average ValueThis value of 1.0 is actually an average for the entire range between points X and Z. Precise estimates of point elasticity shows that the elasticity is 0.67 at point X and 1.5 at point Z. Moreover, the elasticity is different at each point on a straight line demand curve such as this one. The only point in which the elasticity is exactly equal to 1.0 is at point Y, the midpoint between X and Z.This last observation is worth emphasizing. The midpoint elasticity formula effectively estimates the point elasticity at the very midpoint of the overall segment. This means that the elasticity of any point on a demand curve (point elasticity) can be obtained by calculating the arc elasticity with the midpoint elasticity formula such that the desired point is dead center in the middle, the midpoint of the arc.
Recommended Citation:ARC ELASTICITY, AmosWEB Encyclonomic WEB*pedia, http://www.AmosWEB.com, AmosWEB LLC, 20002015. [Accessed: April 20, 2015]. Check Out These Related Terms...       Or For A Little Background...       And For Further Study...      
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State of the ECONOMY
Consumer Price Index W
September 2014
234.170
Up minimally in 1 month Source: B L S
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BLUE PLACIDOLA [What's This?]
Today, you are likely to spend a great deal of time wandering around the downtown area hoping to buy either a wall poster commemorating last Friday (you know why) or a country wreathe. Be on the lookout for defective microphones. Your Complete Scope
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John Maynard Keynes was born the same year Karl Marx died.


"The past is a foreign country; they do things differently there."  Leslie Poles Hartley, Writer


ASEAN Association of South East Asian Nations


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