Presentation on theme: "What is Economics ? (Why does economics exist?) Problem 1. Human Beings have unlimited wants for goods and services. Problem 2. Resources (which are used."— Presentation transcript:
What is Economics ? (Why does economics exist?) Problem 1. Human Beings have unlimited wants for goods and services. Problem 2. Resources (which are used to produce goods and services) are Limited Example: You have a limited income (your resources), but could always want more goods & services than you do now. The Economic problem is Scarcity… Scarcity is the imbalance between: the unlimited wants of humans and the limited means to satisfy those wants
Individual choice: The core of Economics An Economy is: a mechanism through which the use of land, labor, and capital are organized......in an attempt to satisfy the unlimited wants of it's members. Economics is... 1. the study of how individuals, groups, and countries use their limited resources in an attempt to satisfy their unlimited wants. 2. Economics is the study of how individuals, groups, and countries make choices in attempting to satisfy their unlimited wants.
Why make choices? You can never get everything you desire because of limited resources (i.e. income, wealth, time, etc.). This means that one must choose among many different possible alternatives something elseThis means that we could have done something else with our time or with our income. we must always give up some other alternative –In other words we must always give up some other alternative to get something else. Opportunity cost, (This is called: Opportunity cost, (the cost of making a choice) it is measured as the sacrifice of the next best alternative given up by a person, group, or nation. –It could be the amount of money you give up to get a good or service but opportunity cost can be in terms of time or other measure. –It is also, for the most part, subjective. That is it is measured by the person making the choice. –“ There is no such thing as a free lunch”
Decision Making: Marginal Analysis How can individuals, business firms, and nations use our resources and capabilities to make us as well off as possible? Fact: People & Businesses usually exploit opportunities to make themselves better off. Economists use the concept of opportunity cost as a way to visualize these decisions: 1. There is an opportunity cost to everything we do benefit at we are willing to give up. 2. Therefore, a benefit (the opposite of cost) to everything we do must exist and this is measured by what we are willing to give up. Since decisions are rarely all or nothing, this comparison of benefits and costs determine how much of something we choose to have. This is referred to as a trade-off.
Decision Making: Marginal Analysis Moreover, you will only be concerned with the additional benefits and additional costs from your current situation. –Because there is nothing you can do about past costs and benefits (called sunk costs). are greater or equal toThe decision rule is simple: pursue an action where the additional benefits are greater or equal to the additional costs of an action. –It is called marginal analysis because this is the name economists give to the words: additional, next, extra, small change. –In fact you will choose an action or alternative until the marginal benefit = marginal cost (this will fully exploit the opportunity presented to you). Example: The choice of going to college. –All of you decided the marginal benefit of going to college was higher than the marginal cost of going to college.
Example: How many classes do you plan to take in the Fall? –The marginal cost of a class is tuition, books, time. –The marginal benefit for each class is more knowledge gained and closer to graduation. You are probably taking more than 1 class but less than 6. At some point the marginal benefit of taking another class diminishes while the marginal cost is constant. Eventually, taking that 3rd, 4th, 5th, or 6th class is “no longer worth it” compared to the cost. At the point where marginal benefit = marginal cost for you what determines the amount of classes you will take. Much of the material covered in Microeconomics is based on comparing marginal benefits & marginal costs Decision Making: Marginal Analysis
It shows how the market-capitalist system answers the following three fundamental questions: (which every economy faces these because of Scarcity) Microeconomics takes a close look at how individuals and firms make choices What to Produce? How to Produce? For Whom to Produce?
Interaction: How Economies work Interaction of choices: My choices affect your choices and vice versa. Results are often different from intentions. 5 Principles underlying interaction of individual choice 1. There are gains from trade 2. Markets move toward equilibrium 3. Resources should be used as efficiently as possible to achieve individual, group, or a countries goals 4. Markets usually lead to efficiency 5. If markets don’t achieve efficiency, government intervention may improve the well being of participants in the economy (called the welfare of society)
Interaction: How Economies work Resources should be used as efficiently as possible to achieve individual, group, or a countries goals. –they are used to fully exploit all opportunities to make everyone better off. –this means that if we are operating efficiently it will be impossible to make one better off unless we make someone worse off. –Other measurement of well being – equity. This is very difficult to measure, but to gain equity we usually must sacrifice some efficiency. Markets usually lead to efficiency –voluntary trade is done for mutual gain, as long as gains exist people will exploit them If markets don’t achieve efficiency, government intervention may improve the well being of participants in the economy (called the welfare of society)
The study of how choices of households, businesses, and governments affect the aggregate (total) economy. Three large issues of Macroeconomics: (Issue of: Full Employment) 1. Standard of Living - level of consumption of goods and services people enjoy. (Issue of: Full Employment) Economic growth Relationship between: Economic growth and Unemployment. Productivity : Total Production / Number employed given standard 2. The cost of Living - number of dollars it takes to buy goods and services for a given standard of living. Price Stability Inflation and Price Stability : Quantity of Money 3. Economic Fluctuations - the periodic rise and fall of total production in the economy, called the business cycle Recessions and Expansions affecting Unemployment & Inflation: Macroeconomics
Economy wide Interactions Principles that underlie Economy wide transactions 1. One person’s spending is another person’s income When spending on a particular good or type of good increases, the income of resources producing that good increases. 2. Overall spending sometimes gets out of line with the economy’s productive capacity Fluctuations in spending in the economy leads to the business cycle with periodic recessions (a lack of spending compared to the ability to produce goods & services) and inflations (too much spending compared to the ability to produced goods & services) 3. Government policies can change spending Actions of the President, Congress, and the Federal Reserve can influence spending. Macroeconomic policymaking
Graphs Graphs are pictures that show the relationship between two variables A variable is something that can take on more than one value. There are two ways that variables can be related: 1) Positive relationship: variables move in the same direction 2) Negative relationship: variables move in the opposite direction
Example: Positive or Direct relationship Miles driven in a car and the total amount of gasoline used As you drive more you will use up more gasoline. Miles Driven Gasoline used (gallons) 200 10 400 20 600 30 800 40
Miles Driven 200 400 600 800 0Gallons of gasoline used10203040 A graph always starts with labeling the vertical and horizontal axis with the variables (numbering is usually optional) Miles Gasoline used Driven (gallons) 200 10 400 20 600 30 800 40 Next, we plot the points from our table... Then we connect the dots to represent other possible observations and to describe the relationship The graph is read by moving to the right on the horizontal axis........and then moving vertically until you hit the relationship line.
Miles Driven Gallons of gasoline used 200 400 600 800 0 10203040 Miles Gasoline used Driven (gallons) 200 10 400 20 600 30 800 40 If we want more detailed information about this relationship we can calculate the slope of the line Slope = Change in vertical distance Change in horizontal distance = Rise Run = 200 miles 10 gallons = 20 miles gallon 200 miles 10 gallons
This relationship line is constructed “all things equal” Are there other variables could affect the amount of gasoline a car would use for the same amount of miles driven? Tire inflation Weather conditions a well tuned engine amount of weight in car or towing If a car is driven is cold weather it will use more gas for same miles driven How will this affect the relationship line we have drawn?
Miles Driven Gallons of gasoline used 200 400 600 800 0 10203040 Miles Gasoline used Gasoline used Driven (gallons) (gallons) 200 10 12 400 20 24 600 30 36 800 40 48 Use more gas more same amount of miles driven... Adding the variable driving in cold weather has caused the curve to Shift Position! When a third(or more) variable is included in a model it causes the entire curve to shift.
This curve also shows a positive relationship, except it is a not a straight line. The slope of a curved line changes at every point on that curve. you should be able to tell how the slope of the line changes as we move away from the origin. Dealing with curves Production of Cars Cost of Next car Any time a line gets steeper, the slope is getting larger Interpretation: As production gets larger the same increase in production leads to greater increases in costs than before.
Production of Autos Amount of Workers Here is a positive relationship where Y increases but at a smaller rate as X increases. Interpretation: As more workers are added the same increase in workers leads to smaller increases in production. Dealing with curves
The Difference Between a Line and a Curve Equal increments in X lead to diminished increases in Y. Equal increments in X lead to constant increases in Y.
Negative or Inverse relationship Two Variables move in the opposite direction Example: Birthrate and Family income As Family income increases the Birthrate tends to decline
Birthrate (average per family) Family Income (average per family) 0 A negative relationship shows a downward sloping line A B c d e f When we move to the right on the horizontal axis, the relationship line tells us we must move down the vertical axis.
Y X Here is a case of a negative relationship that is not a straight line Interpretation: As X gets larger the same increase in X leads to Y decreasing in greater amounts than when X was smaller Dealing with curves
Y X … as X increases, Y does not change This means that Y is independent of X and vice versa. A straight horizontal or vertical line indicate no relationship between the two variables. A Graph that shows no relationship between the two variables... 20
This is a time series graph. It shows how a variable performs over time. This graph shows Mortgage rates 1976-2009
1.All economic analysis is based on a list of basic principles. These principles apply to three levels of economic understanding. First, we must understand how individuals make choices; second, we must understand how these choices interact; and third, we must understand how the economy functions overall. 2.Everyone has to make choices about what to do and what not to do. Individual choice is the basis of economics. 3.The reason choices must be made is that resources— anything that can be used to produce something else—are scarce. 4.Because you must choose among limited alternatives, the true cost of anything is what you must give up to get it— all costs are opportunity costs. Summary
5.Many economic decisions involve questions not of “whether” but of “how much. Such decisions must be taken by performing a trade-off at the margin—by comparing the costs and benefits of doing a bit more or a bit less. Decisions of this type are called marginal decisions, and the study of them, marginal analysis, plays a central role in economics. 6.The study of how people should make decisions is also a good way to understand actual behavior. Individuals usually exploit opportunities to make themselves better off. If opportunities change, so does behavior: people respond to incentives. 7.Interaction—that my choices depend on your choices, and vice versa, adds another level to economic understanding. Summary
8.The reason for interaction is that there are gains from trade: by engaging in the trade of goods and services with one another, the members of an economy can all be made better off. Underlying gains from trade are the advantages of specialization, of having individuals specialize in the tasks they are good at. 9.Economies normally move toward equilibrium—a situation in which no individual can make himself or herself better off by taking a different action. 10.An economy is efficient if all opportunities to make some people better off without making other people worse off are taken. Efficiency is not the sole way to evaluate an economy: equity, or fairness, is also desirable. There is often a trade-off between equity and efficiency. Summary
11.Markets usually lead to efficiency, with some well-defined exceptions. 12.When markets fail and do not achieve efficiency government intervention can improve society’s welfare. 13.One person’s spending is another person’s income. 14.Overall spending in the economy can get out of line with the economy’s productive capacity, leading to recession or inflation. 15.Governments have the ability to strongly affect overall spending, an ability they use in an effort to steer the economy between recession and inflation. Summary