Google
Monday 
July 27, 2015 

AmosWEB means Economics with a Touch of Whimsy!

AmosWEBWEB*pediaGLOSS*aramaECON*worldCLASS*portalQUIZ*tasticPED GuideXtra CrediteTutorA*PLS
Today's Index
Yesterday's Index
209.7

Help us compile the AmosWEB Free Lunch Index. Tell us about your last lunch.

Skipped lunch altogether.
Bought by another.
Ate lunch at home.
Brought lunch from home.
Fast food drive through.
Fast food dine in.
All-you-can eat buffet.
Casual dining with tip.
Fancy upscale with tip.

More About the Index
Worst letter?

X.
Q.
Z.
V.
O.
U.

LEGAL CLAIMS: Ownership of the physical goods, services, and resources that make up the real side of the economy. Legal claims are a key feature of the paper, or financial side of the economy. Transferring legal claims is the primary method of diverting income from household saving to investment and government borrowing. Legal-claim buyers loan income and legal-claim sellers borrower income.

Visit the GLOSS*arama


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 Example

A Standard Demand Curve
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 Value

This 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.

<= AMERICAN ECONOMIC ASSOCIATIONASSUMPTION =>


Recommended Citation:

ARC ELASTICITY, AmosWEB Encyclonomic WEB*pedia, http://www.AmosWEB.com, AmosWEB LLC, 2000-2015. [Accessed: July 27, 2015].


Check Out These Related Terms...

     | point elasticity | coefficient of elasticity | midpoint elasticity formula | endpoint elasticity formula | point elasticity |


Or For A Little Background...

     | elasticity | price elasticity of demand | price elasticity of supply | income elasticity of demand | cross elasticity of demand |


And For Further Study...

     | elasticity and demand slope | elasticity and supply intercept | demand elasticity and total expenditure | elasticity alternatives | elasticity determinants |


Search Again?

Back to the WEB*pedia


APLS

State of the ECONOMY

Producer Price Index Final Demand
May 2015
109.9
Up 0.5% from April 2015 Soure: BLS.gov

More Stats

GREEN LOGIGUIN
[What's This?]

Today, you are likely to spend a great deal of time at the confiscated property police auction hoping to buy either a travel case for you toothbrush or a looseleaf notebook binder. Be on the lookout for jovial bank tellers.
Your Complete Scope

This isn't me! What am I?

Woodrow Wilson's portrait adorned the $100,000 bill that was removed from circulation in 1929. Woodrow Wilson was removed from circulation in 1924.
"Old age isn't so bad when you consider the alternative. "

-- Cato, Roman orator

APR
Annual Percentage Rate
A PEDestrian's Guide
Xtra Credit
Tell us what you think about AmosWEB. Like what you see? Have suggestions for improvements? Let us know. Click the User Feedback link.

User Feedback



| AmosWEB | WEB*pedia | GLOSS*arama | ECON*world | CLASS*portal | QUIZ*tastic | PED Guide | Xtra Credit | eTutor | A*PLS |
| About Us | Terms of Use | Privacy Statement |

Thanks for visiting AmosWEB
Copyright ©2000-2015 AmosWEB*LLC
Send comments or questions to: WebMaster