applied microeconomics l.
Skip this Video
Loading SlideShow in 5 Seconds..
Applied Microeconomics PowerPoint Presentation
Download Presentation
Applied Microeconomics

Loading in 2 Seconds...

play fullscreen
1 / 26

Applied Microeconomics - PowerPoint PPT Presentation

  • Uploaded on

Applied Microeconomics Asymmetric Information Outline Adverse selection Signaling Screening Readings Kreps: Chapter 18 Perloff: Chapter 19 Zandt: 12C Introduction What happens when some market participants know more than others? Examples:

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Applied Microeconomics' - ostinmannual

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
applied microeconomics

Applied Microeconomics

Asymmetric Information

  • Adverse selection
  • Signaling
  • Screening
  • Kreps: Chapter 18
  • Perloff: Chapter 19
  • Zandt: 12C
  • What happens when some market participants know more than others?
  • Examples:
    • Sellers who know more about the quality of their product than prospective buyers
    • Workers who know more about their skills than prospective employees
    • Insiders who know more about a firm’s value than outside shareholders
types of information asymmetries
Types of Information Asymmetries
  • Unobservable characteristics: adverse selection
  • Unobservable actions: moral hazard
adverse selection
Adverse Selection
  • In 1994, the average car depreciated 37% in its first year and 13% more under the second year
  • 35% of all cars were sold through car dealerships, typically offering warranties
  • The average price of a used car in 1994 was about $11,500, but the average private-sale price for a used car was about $2,000 less
adverse selection7
Adverse Selection
  • “Adverse selection occurs when an informed individual’s trading decision depends on her unobservable characteristics in a manner that adversely affects the uninformed agents in the market.”
example market for lemons
Example: Market for “Lemons”
  • Suppose two types of cars – good quality in share g and bad quality “lemons” in share 1-g
  • Finite number of sellers with reservation prices 1800 Euros for good cars and 800 Euros for bad cars
  • Numerous risk-neutral buyers with reservation prices 2000 Euros for good cars and 1000 Euros for lemons
example market for lemons10
Example: Market for “Lemons”
  • If quality observable to buyers, then both types of cars would be traded at prices 2000 and 1000 respectively
  • If quality unobservable to buyers, and both cars are offered, then buyers are prepared to pay 2000g+(1-g)1000=1000+1000g
  • Sellers of good cars are willing to sell when 1000+1000g≥1800, or in other words if g≥80%
example market for lemons11
Example: Market for “Lemons”
  • What if the share of good cars is less than 80%?
  • Then only bad cars are offered, and, the buyers anticipating this, offer 1000
  • Good cars are thus driven out of the market!
  • Screening
  • Signaling
  • Remember how firms practicing second-degree price discrimination could choose the quality and tariffs of goods such that different types self-select different goods/bundles?
  • In the same manner a firm with no information can screen possible counterparties
  • “Screening refers to activities undertaken by the party without private information in order to separate different types of the informed party along some dimension”
  • In markets with adverse selection, an informed party of high quality may overcome the adverse selection problem by signaling his type
  • However, the cost of the signal must be such that:
    • It is not in the interest of an informed party of low quality to imitate and the send the same signal
    • It is not too expensive for the high type to signal
  • High-ability workers can signal their ability to firms by acquiring a certain level of education
  • Entrepreneurs with profitable projects can signal the profitability of the project to VC:s by offering holding on to an equity stake in the venture
  • Car dealers can signal the quality of a used car by offering a warranty
spence s model of labor market signaling
Spence’s Model of Labor Market Signaling
  • Consider a competitive labor market with workers of marginal productivity L in share q, and workers of marginal productivity H>L in share 1-q
  • Allworkers are assumed to have a reservation wage of 0
  • Firms want to hire workers to perform a task, but ability is not observable to them
spence s model of labor market signaling19
Spence’s Model of Labor Market Signaling
  • With symmetric information low productivity workers would be paid a wage of wL=L and high productivity workers a wage of wH=H
  • With asymmetric information and no way for employers to separate types there would be an equilibrium where all workers received a wage of w=qL+(1-q)H
separating equilibrium
Separating Equilibrium
  • Suppose now that high productivity workers can get a degree attending school at a cost (psychic and economic) c and that low productivity workers cannot graduate from school
  • Assume for simplicity that the productivity of the worker is not affected by the education
pooling equilbria
Pooling Equilbria
  • If H-c>qL+(1-q)H, or equivalently q(H-L)>c, only a separating equilibrium, where only high-productivity workers go to school and firms rightly believe that only graduates are of high productivity, is possible
  • If on the other hand H-c<L, or equivalently H-L<c, then only a poolingequilibrium with a uniform wage for everyone is possible
  • If q(H-L)≤c≤H-L, then both types of equilibria are possible









  • If education does not raise productivity, then signaling is often socially inefficient
    • In our example, output and total wages are the same with and without signaling, but education is costly
    • Low productivity workers are definitely worse off
    • If w>H-c>L, then high-ability workers are also worse off
  • Reason is that private returns to education exceeds net social returns
  • Education can be socially efficient when it raises total output (lemons market) or productivity
  • Embarrassment of riches
    • Hard to make predictions:
      • Not only both separating and pooling equilibria
      • Also separating equilibria with different costs of education for high-productivity workers
    • Some equilibria Pareto dominate others
  • Self-confirming equilibria are possible:
    • Suppose employers believe that in addition to education some observable and completely independent characteristic such as sex or skin color is a signal of productivity
    • Even if the share of low- and high-productivity workers is the same among men and women, we could have a separating equilibrium among male workers and a pooling equilibrium among female workers
  • Adverse selection occurs when asymmetric information about characteristics affect some party adversely
  • Screening is when the uninformed party designs contracts to elicit information about the characteristics of the informed party
  • Signaling is when the informed party takes a costly action in order to convey information about his type to the uninformed party