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HARD MONEY: Historically money that is in the form of precious metals, especially gold. In modern times, any national currency that is expected to retain its value (and even appreciate in value), and is readily acceptable for most international transactions. The U.S. dollar, German marc, and Swiss franc tend to be near the top of the list of hard money (also termed hard currency).
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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, 20002016. [Accessed: October 26, 2016]. 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 Urban
November 2015
237.336
Up 0.0% from Oct. 2015 Source: BLS
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WHITE GULLIBON [What's This?]
Today, you are likely to spend a great deal of time searching for rummage sales looking to buy either a decorative windchime with plastic or a flower arrangement for that special day for your mother. Be on the lookout for empty parking spaces that appear to be near the entrance to a store. Your Complete Scope
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There were no banks in colonial America before the U.S. Revolutionary War. Anyone seeking a loan did so from another individual.


"The way to gain a good reputation is to endeavor to be what you desire to appear. "  Socrates, philosopher


ADR American Depositary Receipt, Asset Depreciation Range


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