Economics Lecture Two
Economics Lectures - [1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14]
Second Lecture â Supply and Demand
Instructor, Andy Schlafly
Introduction
Weâve had our first introduction to economics and are ready explore the topic in greater detail. Remember that this course is about the purchase and sale of goods and services in free enterprise. By âfree enterprise,â I mean business transactions that are "free of" interference by someone other than the buyer and seller, such as government. Free enterprise has little or no government interference in the setting of prices and selling of the goods or services.
The first obvious question about the purchase and sale of goods is this: what determines the price and quantity of goods sold?
We could spend the remainder of this course on that simple question. Thousands of people and factors affect the pricing of a good or service, so this question is not as simple as it looks. Assumptions have to be made in order to draw conclusions. In some cases, price behavior baffles even the greatest experts in the field.
For example, the pricing of stocks freely traded on the stock exchanges is often a mystery. The value of a companyâs stock reflects how much people are will to pay for it. A company that has one billion shares of stock in the market, valued at $15 per share, has a market value of $15 billion. Logic dictates that when a stock increases its value, then the company is increasing its overall value.
During the internet âdot-comâ boom of the late 1990s, stock prices of companies that were losing money seemed to disprove every basic principle of economics. Sometimes it seemed like the more a dot-com company lost money, the higher its stock would go!
But that was an exception that could be understood by questioning typical assumptions. It was also highly unusual. More often, stock value in a company that consistently loses money declines to approach zero. The stock value in a company that increases its profits each year increases to reflect those higher profits.
Stock prices on the New York Stock Exchange and NASDAQ (the stock exchange for new and often high-tech companies) are determined entirely by âbidâ and âaskâ prices of the buyers and sellers. Someone will âbidâ a certain amount to buy a stock, and a seller will âaskâ for a certain price. When the bid and ask amounts equal, then a sales transaction occurs. Prices can move very quickly and unpredictably when millions of people are involved.
The price that a stock trades on the exchange is where the âsupplyâ by sellers equals the âdemandâ by buyers. When a seller of stock asks too high a price, then there are no buyers and the stock does not trade. When a buyer of stock offers too little a price, then there are no sellers and the stock does not trade. The transaction only occurs when SUPPLY EQUALS DEMAND.
Today we will discuss this important principle of economics and many of the surrounding issues.
Supply and Demand
For any given good or service, there is a supply and demand. The supply consists of quantity and price. The price has enormous influence over the quantity. No company can afford to build cars to sell at a price of only $1. But at a sales price of $30,000, a vast number of cars can be built. The cause is price, and the effect is quantity.
The demand for a good can be described in terms of price and quantity also. At a given price, there is an amount of demand by the public for the good. A billion people might buy a car if the price were only $1. At a much higher price of $30,000, the demand drops to a quantity in the millions range. At a still higher price of $100,000, the demand falls much further to the thousands range.
Because supply and demand can both be expressed in terms of price and quantity, they can be plotted on the same graph. The y-axis is typically price, and the x-axis is usually quantity. The supply curve is usually upward sloping: the higher the sales price, the higher the quantity that companies can produce for sale. That is because higher sales prices bring in greater revenue to fund the production costs.
The supply and demand is the most basic relationship in all of economics. It usually looks like this:[1]
The above model for supply and demand helps us to consider the effect of shifts in demand and supply. First consider an increase in demand:
An increase in demand causes price to rise. The new equilibrium is at a point with higher price and greater quantity than before. What could cause an increase in demand? For gasoline, more people driving would cause an increase in demand. For heating oil, a colder winter would cause an increase in demand. For sports entertainment, a close rivalry can cause an increase in demand (spectators). In all those cases, price and quantity tend to rise. If there is a decrease in demand, then the opposite is generally true: prices and quantity tend to decrease. Next consider an increase in supply. Suppose farmers have better weather, for example, causing more crops at the harvest. Or suppose there is discovery of huge new oil reserves underground. Or suppose a new invention, such as Eli Whitneyâs cotton gin, increases the production of a good (cotton). This curve shows what happens when there is an increase in supply:
Can you interpret that? When the supply curve shifted downward as supply increased, the price decreased but the quantity increased. The new equilibrium is at lower price and greater quantity than before. Consumers are happier as supply increases. The discovery of new oil reserves, or inventions like the cotton gin, make consumers better off.
Equilibrium & Information
Consider these three basic principles of economics:
- When demand exceeds supply at a given price, the price tends to rise. Likewise, when supply exceeds demand, the price tends to decrease.
- A rise in price tends to increase supply and decrease demand. Conversely a fall in price tends to decrease supply and increase demand.
- Price tends to move towards the amount at which the quantity in demand is equal to the quantity in supply: SUPPLY EQUALS DEMAND.
Note the use of the verb âtendâ in the laws of economics cited above. Companies that consistently lose money âtendâ to go bankrupt and out of business. But it does not happen immediately, especially if the company is large. It takes time for the market to come to equilibrium. Ultimately supply does equal demand, but only after enough time and activity passes for the conditions to attain equilibrium.
âEquilibriumâ is âwhere things are goingâ or where they have already arrived. The equilibrium for the universe is complete disorder and chaos, with every creature extinct. A constant increase in entropy is what drives situations to their equilibrium. (Devolution is the process, not the so-called evolution.) Economic equilibrium is when all the imbalances in selling and buying prices have disappeared and there are no more trends to different price levels. Randomness and profit-making pressures drive pricing towards equilibrium.
The ultimate equilibrium when there is perfect competition occurs when the marginal revenue to the seller equals its marginal cost of the product. In other words, the supplier keeps producing more and more goods until its marginal profit on each extra good falls to very close to zero. That profit decline may be because the goods are not selling as quickly or due to unsold goods. For example, the first SUV produced by Ford may sell at a high price, but its last SUV in a given year will have to be discounted heavily. Ford doesnât want to make any more SUVs in a given year that it might have to take a loss on. It produces just enough so that marginal revenue falls to marginal cost, as best as can be predicted.
Imbalances in information are a reason for the delay in pricing to reach equilibrium. Buyers do not immediately realize when they can obtain the same good more cheaply another way. For many years people continued to pay high costs for renting telephones after it became legal to buy inexpensive ones. The effects of competition are not often felt overnight. A lower-priced competitor has to educate the public of the availability of its goods, and that takes time.
There is also a more permanent imbalance in information between the buyer and seller of a good. The seller always knows more about his good than the buyer does. The seller does not want to disclose the disadvantages, weaknesses, defects, and outright dangers of his good. The buyer has to beware in paying money to the seller for a good: caveat emptor (Latin for âlet the buyer bewareâ).
Tobacco companies did not want to disclose that cigarettes cause cancer. Abortion providers do not want to disclose that abortions cause breast cancer. Used car dealers do not want to disclose that a car is a lemon (i.e., constantly needs fixing). Food manufacturers do not want to disclose all the fat and artificial ingredients in their products.
Governmental regulations require some of these disclosures. This may be the best and only effective type of governmental regulation. Food packaging now must state what the ingredients are and how much fat is contained. The buyer doesnât have to guess about this information. The buyer must still beware, but can do so with more information than before.
Price Discrimination
The term âprice discriminationâ sounds ugly, but it means selling the same good or service at different prices to different people. It is an attempt by a seller to capture additional money from buyers who are willing to pay more.
Airline tickets are an example. Businesses are willing to pay more for airline tickets for their employees to travel to business meetings than tourists are. Why? Because the businessmen are traveling to make more money for their company, and the airline ticket can be paid out of their profits. If they are flying to do a deal worth $100,000, then theyâre willing to pay many thousands of dollars for the airline ticket. Not so for tourists who fly.
The airline wants to sell the same seat at a price low enough for the tourist to pay, and then at a different, much higher price for the businessmen. This is price discrimination, because it distinguishes or discriminates based on who the buyer is. âPerfect price discriminationâ sells each unit of a good at the maximum amount each individual buyer is willing to pay.
There are laws against price discrimination, but most sellers find clever ways to do it anyway. Airlines distinguished between business customers and tourists by its âSaturday night stay-overâ rule. If the traveller reserves the return flight to include staying over at least one Saturday night, then he is likely a tourist. If he flies out and back in the same week without staying through the weekend, then he is likely a businessman. So the airline tickets were then priced much more cheaply for those who stay over at least one Saturday night.
In general, price discrimination depends on the existence of obstacles to prevent buyers from reselling their goods to other buyers. If the same good is sold at $X to person A and $Y to person B, and X<Y, then person A could buy an extra good and sell it to person B at less than $Y. The price discrimination would collapse due to the resale market.
But some goods cannot be resold. Goods that are personal to the buyer, like a tailored suit or dress, cannot be resold. Price discrimination works fine for personalized goods or exclusive markets, because there is not a resale market to destroy the discrimination.
Minimum Wage and Price Controls
So far we have been talking about economic exchanges in the absence of government controls. But the government does interfere in many ways in our economy. America enjoys more free enterprise than any other large country, but we are still heavily regulated.
During World War II, the government imposed controls to prevent companies from raising prices during the war. The needs of our military for goods increased demand that would ordinarily shift the demand curve and increase prices. But the government prohibited this from happening by limiting price increases.
Controls on prices (and also wages) were also imposed to control inflation in the early 1970s. A war in the Middle East, and assistance in that war by the United States of Israel, caused the Arab nations to reduce their supply of oil to us. That created gasoline shortages and increased energy costs, which then drove up inflation. Price controls were designed to limit the increases.
Today, the government prohibits employers from paying wages below a certain amount per hour, called the âminimum wage.â It is now $7.15 per hour in New Jersey, but only $5.15 per hour nationwide. If you work 40 hours a week for 50 weeks, or a total of 2000 hours, then that translates to a yearly salary of $10,300. It is nearly impossible to support a family that amount in most areas of the country, and many politicians are constantly demanding an increase in the minimum wage.
Unfortunately, it is even more difficult to survive without a job at all, which is what happens to many people (particularly teenagers) when the minimum wage is increased. Employers who would hire someone to work at $4 per hour might not be able to hire them at $5.15 per hour. Isnât a job at $4 an hour better than none at all?
Moreover, illegal aliens find a wage of even $2 an hour better than what they could make in their homeland. Companies move operations offshore to take advantage of places that do not have minimum wages as high as ours. Alternatively, workers enter this country illegally to work at low wages and displace American workers, according to several lawsuits.
Minimum Wage and Dropping Out of School
Researchers have found that one effect of raising the minimum wage is that more students drop out of school, or do not go on to college, because they can make more money working at jobs than they could before. This can be understood as follows:
- Suppose that "x" number of students quit school to work at jobs when the minimum wage is $6 per hour.
- If the minimum wage is raised from $6 per hour to $7 per hour, then jobs appear more attractive to students and even more will leave school than before.
- Therefore raising the minimum wage causes more students to leave school in order to work at jobs.
Other studies show, however, that the more education that someone has, the higher their average income is. Students who complete four-year colleges make more money on average than students who completely only two-year colleges, for example. Students who complete two-year colleges likewise have higher average incomes than students who end their education after high school.
Raising the minimum wage thus entices students to take advantage of a "short-term" benefit of the higher wage, but they are worse off in the "long-run". They would make more money by staying in school and not being enticed by the increase in the minimum wage.
Socialized Medicine
The single biggest industry in the United States is health care, and it is sharply increasing in expenditures each year. It has three major components: government-controlled (Medicare and Medicaid), insurance-controlled, and private pay or uninsured. Each year, the demands for the government to take over the field grow louder, as insurance costs sky-rocket.
Most other countries have some form of socialized medicine. In the countries of Canada, North Korea and Cuba, it is actually illegal to pay money to a doctor simply to see you. The government control there is so great that you can only see a doctor paid by the government in those countries. In England, there is a two-tiered system: good care is provided to those who can afford to pay for it, and free but inferior care is provided by the government to those who cannot.
The Canadian government destroyed free enterprise in medicine there, and took over the health care system. The government now sets limits on wages and prices. Lowering the wages and prices prevents supply from rising to satisfy demand. Because demand is much greater than supply, patients have to wait a long time to see a doctor. There is a lower survival rate from cancer in Canada than the United States because of the delays in diagnosis and treatment there.
If an elderly Canadian is vacationing in Florida and falls and breaks his hip, which is very painful, the Canadian system of health care will not even reimburse the patient for surgery at the nearest hospital. Instead, the patient must fly back to Canada in excruciating pain to be operated on by a government-controlled doctor there.
In the United States, where health care still includes free enterprise, a patient can enter a doctorâs office or hospital at any time and receive services based on a promise to pay for them by check or cash. Prices vary, and it is worth shopping around. Immediate care always remains available at some price.
Assignment
Read, and reread, the lecture. Complete the homework assignments through the level in which you choose to enrol in this course:
1. The supply of a good, and the demand for that good, determine both the ______ and ______ at which the good is sold, at least in a market free from interference or control by government.
2. Suppose the price demand curve is P = $30 - Q, where P is price and Q is quantity. Also suppose the price supply curve is P = $6 + Q. At what price and quantity will the good be sold?
3. When the supply of a good or service increases, such as increasing the number of oil wells, what happens to the market price of oil? Explain. When the demand for a good a good or service increases, such more people driving cars that need gasoline (refined oil), what happens to the market price of oil? Explain.
4. Suppose 1000 persons in a town each have the following weekly demands for gas, and the gas stations have the following weekly supplies:
Gallons Demand Price/gallon Supply Price/gallon
10 $5 $1
20 $4 $2
30 $3 $3
40 $2 $4
(A) What is the price and overall quantity of gas sold each week?
(B) Suppose Congress declares war and imposes a price control of $1 per gallon. At what price and overall quantity will gas sell each week?
5. For most of our nation's history it used tariffs rather than taxes on income in order to provide money for the national (federal) government in Washington, D.C. What is the effect on the supply curve for a good imported from China if the U.S. government imposed a $1 tariff on it? Would that cause more or less of that good to be purchased? Why?
6. Sometimes governments impose quotas rather than tariffs on imports. By limiting the amount of a foreign good that can be sold in this country, Americans who make the same good have an easier time selling their good with less competition. What effect does a quota have on the supply curve and the equilibrium price for an imported good? Who makes more money because of a quota, and who loses the most from it?
7. Suppose you work for a store and its owner arrives one day and tells you that wants to set new prices for every good in the store. He declares that he is the owner, and he should be able to sell his goods and whatever price he chooses. Will he succeed in this strategy, or is there another force outside the control of the owner that will determine the sales prices? Explain to the owner what your opinion is of his approach.
Honors
Write an essay of about 300 words total on one or more of the following topics:
7. Should government regulations require and monitor honest and full disclosure of information by sellers to buyers?
8. Should price discrimination be illegal?
9. What is an economic incentive for excluding homeschooled athletes from high school sports? Should that be legal?
10. Describe your view of if or how government should regulate medical prices.
11. âEconomic theory of law and the public domain - When is Piracy Economically Desirable?â See http://lexnet.bravepages.com/media1.html
12. What is your view of the minimum wage? Should it be increased?
Sources
- â The graphs here use Wikipedia open source images.