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Economic decisions · Economics and scarcity

Needs, goods and scarcity

It's Friday night at the high school football game. 300 students are lined up at the snack bar, but only 120 hot dogs are left. Who gets one, and why? Keep that line in mind: we'll come back to it.

Everyone would like more time, more money and more of almost everything. No country, company or person has unlimited resources to achieve this. From this mismatch, as old as humanity itself, economics is born as a discipline: the rigorous study of how limited resources are allocated among alternative ends.

Needs and wants

Visual comparison between need and want, highlighting that the difference depends on each person's situation and not just on the object. Need its absence prevents functioning Want improves wellbeing, is dispensable the classification depends on the person, not just on the object

Economists also sort needs by urgency. Primary needs (food, housing, basic health care, clothing) are required to live; secondary needs (streaming, vacations, a gym membership) make life more comfortable or enjoyable. When income falls, people usually cut secondary needs first.

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Explain in your own words what an economic need is and how it differs from a simple want. Give two examples of each related to your life as a student.

Explain in your own words what an economic need is and how it differs from a simple want. Give two examples of each related to your life as a student.

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Needs change over time: ask an older person which things in your daily life did not exist when they were your age (cell phone, internet, wireless headphones). What does…

Needs change over time: ask an older person which things in your daily life did not exist when they were your age (cell phone, internet, wireless headphones). What does that show about the idea that human needs are unlimited?

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A family reviews its monthly expenses: rent, streaming service, food, gym, medicines, and vacations. Classify each expense as a primary or secondary need and explain…

A family reviews its monthly expenses: rent, streaming service, food, gym, medicines, and vacations. Classify each expense as a primary or secondary need and explain which ones could be cut with the least cost if their income fell.

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Free goods and economic goods

Classification of goods according to their availability, distinguishing between free and economic goods, and according to their tangibility into material goods and services. Free good abundant, no cost Economic good scarce, requires a cost the classification can change over time or place
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Classify the following goods as free or economic goods and justify each decision: the air you breathe in the countryside, a sandwich from the cafeteria, sunlight, a…

Classify the following goods as free or economic goods and justify each decision: the air you breathe in the countryside, a sandwich from the cafeteria, sunlight, a movie ticket, bottled water, and the school's Wi-Fi.

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Distinguish between physical goods and services, and classify the following: a haircut, a backpack, a dental check-up, a notebook, and the bus ride to school. Justify…

Distinguish between physical goods and services, and classify the following: a haircut, a backpack, a dental check-up, a notebook, and the bus ride to school. Justify each classification.

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Water falls free from the sky, and yet tap water is paid for. Explain, using the concepts of free good and economic good, what turns it into an economic good: what work…

Water falls free from the sky, and yet tap water is paid for. Explain, using the concepts of free good and economic good, what turns it into an economic good: what work and what infrastructure lie behind the tap.

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Relative scarcity

Flow diagram of the economic problem: the tension between limited resources and unlimited needs forces us to choose and give things up. Resources limited Needs unlimited Choose and give up Scarcity
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Explain what it means for a resource to be scarce. Identify three scarce resources in your school (spaces, equipment, someone's time) and describe what decisions each…

Explain what it means for a resource to be scarce. Identify three scarce resources in your school (spaces, equipment, someone's time) and describe what decisions each one forces people to make.

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The diagram summarizes the basic economic problem, but one of the boxes is covered with a question mark. State which concept is missing and explain with one sentence…

The diagram summarizes the basic economic problem, but one of the boxes is covered with a question mark. State which concept is missing and explain with one sentence what each step of the diagram means.

Unlimited needs Limited resources ? Choices must be made
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Time is also a scarce resource. List everything you would like to do on a Sunday and estimate the hours each activity would take: if the total exceeds the hours in the…

Time is also a scarce resource. List everything you would like to do on a Sunday and estimate the hours each activity would take: if the total exceeds the hours in the day, explain what basic economic problem you are facing and how you solve it.

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Choice and opportunity cost

Scarcity forces you to choose, and every choice has a hidden price tag, even when no money changes hands.

Choosing between a movie and bowling: the option given up is the opportunity cost. Saturday and 20 dollars Movies (chosen) you get the film Bowling (given up) = opportunity cost

The same idea helps when a wish list costs more than your budget. Rank the items by the satisfaction you get per dollar and fund them from the top until the money runs out. The items left over are what you give up. Need versus want helps too: needs usually come first.

Now think about a school with 4 flexible teaching hours that can fund either a remedial workshop or a robotics class. Using the hours on one project means giving up the other, so each project's opportunity cost is the other one. Neither choice is technically wrong; the best one depends on the school's goals. The production possibilities curve (PPC) shows this trade-off on a graph, and you will use it later in the course.

The same logic explains why a price on a shared resource changes behavior. When farmers use water from a common aquifer for free, each one ignores the opportunity cost of the water. Once water has a price, every farmer compares what a gallon is worth in a crop with what it costs, so they switch to efficient irrigation or less thirsty crops.

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Explain why we say that scarcity forces us to choose. Illustrate this with an example of your own where you have $\$20…

Explain why we say that scarcity forces us to choose. Illustrate this with an example of your own where you have $\$20$ and a whole Saturday ahead of you: what options you consider, which one you choose, and what you give up.

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Alex has $\$100$ a month and his wish list (clothes, video games, going out, saving for a trip) adds up to $\$160$. a) What economic concept does that difference…

Alex has $\$100$ a month and his wish list (clothes, video games, going out, saving for a trip) adds up to $\$160$.

  1. a) What economic concept does that difference illustrate?
  2. b) Propose a method for prioritizing the list and explain what criterion it uses (need versus want, satisfaction per dollars spent).
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The administrative team at your high school has a margin of $4$ teaching hours per week of flexible allocation and is debating between two incompatible projects due to…

The administrative team at your high school has a margin of $4$ teaching hours per week of flexible allocation and is debating between two incompatible projects due to time constraints:

  • Project A: Allocate the $4$ hours to individualized remedial workshops in basic skills for $40$ students at risk of dropping out.

  • Project B: Allocate the $4$ hours to an advanced robotics and applied programming classroom for $20$ gifted students.

  1. a) Explain this dilemma using the concepts of opportunity cost and production possibilities frontier: justify why neither of the two options is technically wrong, but both entail an inevitable sacrifice of value for the school community.
  2. b) Design a rubric with three objective criteria (one for academic efficiency, one for distributive equity, and one for long-term socioeconomic impact) that allow the school board to justify the final decision in a reasoned manner.
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Shortage, surplus, and prices

At the snack bar, 300 students want a hot dog but only 120 are for sale. That gap has a name.

Bars comparing the quantity demanded (300) with the quantity supplied (120) of hot dogs; the difference is the shortage. Quantity demanded: 300 Supplied: 120 Shortage: 180 At the current price of 4 dollars.

This is why prices of scarce goods, such as airline or concert tickets around a holiday weekend, rise as supply sells out: the price signals relative scarcity. A good that can be copied at no extra cost, like an app, has a marginal cost near zero, so the seller can serve any number of users without running out. Scarcity does not vanish, though: servers, electricity, minerals for chips, and engineers' time are still scarce, which is why a technology company's claim that it has defeated scarcity is wrong.

When a good is free at the point of use, such as dishes in an all-you-can-eat dining hall paid with a flat fee, the marginal cost to you of one more plate is $\$0$. People take more than they can eat and food is wasted, even though society still pays for the ingredients and labor. Charging per item makes that cost visible again.

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The school cafeteria bakes $200$ sandwiches a day and there are $500$ students who would like to buy one for $\$2…

The school cafeteria bakes $200$ sandwiches a day and there are $500$ students who would like to buy one for $\$2$.

  1. a) Is there a shortage of sandwiches at that price? Justify your answer using the data.
  2. b) Propose two different ways of distributing the available sandwiches and explain the criterion used by each.
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The school parking lot has $40$ spaces and $95$ applications have been submitted. a) Is there a shortage of spaces? Justify your answer using the data. b) Compare three…

The school parking lot has $40$ spaces and $95$ applications have been submitted.

  1. a) Is there a shortage of spaces? Justify your answer using the data.
  2. b) Compare three criteria for allocating the spaces (charging a price, holding a lottery, awarding them by seniority) and assess what each one gains and loses.
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Train tickets for the December holiday weekend sell out weeks in advance and prices rise as the date approaches. a) Explain the relationship between the relative…

Train tickets for the December holiday weekend sell out weeks in advance and prices rise as the date approaches.

  1. a) Explain the relationship between the relative scarcity of seats and the price.
  2. b) Why does the same not happen with a good that can be produced without limit, such as an app? Reason out the difference.
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Factors of production

A food truck owner in Houston needs a street spot, a cook, a truck and grill, and an idea that customers will pay for. Economists call these inputs factors of production.

The four factors of production: land, labor, capital, and entrepreneurship. Land natural resources Labor work of people Capital tools and machines Entrepreneurship ideas and risk

Each factor earns income: land earns rent, labor earns wages, capital earns interest, and entrepreneurship earns profit. All four are limited, so even a high-tech economy runs into scarcity: chips need minerals (land), data centers need electricity and equipment (capital), and software needs engineers' time (labor).

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A technology company states in its advertising campaign: «Thanks to artificial intelligence and solar-powered data centers, the marginal cost of copying and distributing…

A technology company states in its advertising campaign: «Thanks to artificial intelligence and solar-powered data centers, the marginal cost of copying and distributing information is zero. Technology has finally defeated scarcity».

  1. a) Refute this statement by analyzing at least two productive resources essential for sustaining this digital economy (for example, critical minerals for processors, continuous electrical power, or human attention and time) that remain strictly scarce.
  2. b) Using the distinction between absolute physical scarcity and relative economic scarcity, explain why an almost infinite abundance of information does not eliminate the economic problem, but rather shifts the opportunity cost to other links in the system.
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Economic systems

Because resources are scarce, every society must answer three questions: What to produce? How to produce it? For whom to produce it? An economic system is the way a society answers them.

Four economic systems and who decides in each: custom, government planners, prices, or a mix of markets and government. Traditional custom decides Command government plans Market prices and profit Mixed markets + government

No real economy is pure. Private firms produce most goods in the US, but government provides roads and public schools and sets rules. A mixed system can also use markets inside rules: for example, a state can cap total water use and let farmers buy and sell shares of that cap, so the water goes to the crops that value it most. Charging per gallon (as in a market) instead of a flat fee changes how much each user takes.

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In the Ria region, irrigation water is paid for with a flat annual fee and the fields waste water; in Vala, it is paid for per liter consumed and water use has fallen by…

In the Ria region, irrigation water is paid for with a flat annual fee and the fields waste water; in Vala, it is paid for per liter consumed and water use has fallen by $30\ \%$.

  1. a) Explain how the price manages scarcity in each system.
  2. b) Analyze the equity problem that charging per liter can create and propose a solution that keeps the saving.
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For years, farmers in a municipality freely irrigated their fields with water from a common aquifer at no cost. After a prolonged drought, the water level drops…

For years, farmers in a municipality freely irrigated their fields with water from a common aquifer at no cost. After a prolonged drought, the water level drops drastically and the city council decides to limit extraction and charge $0.40\text{ \$}$ for each cubic meter consumed.

  1. a) Justify the transition of water from a free good to an economic good and predict what immediate changes this price will cause in irrigation techniques and crop selection, using the concept of opportunity cost.
  2. b) It is proposed to allow farmers with higher-yield crops to purchase part of their water quota from those who grow traditional cereal crops. Analyze the effects of authorizing this water rights market on economic efficiency and on equity among the locals.
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In a university residence hall, the dining hall is included in a fixed monthly fee (flat-rate full board). At the end of the semester, it is found that $25.0\ \%$ of the…

In a university residence hall, the dining hall is included in a fixed monthly fee (flat-rate full board). At the end of the semester, it is found that $25.0\ \%$ of the food served is thrown directly into the trash.

  1. a) Interpret this waste from the perspective of marginal cost for the resident: why does a good perceived as free at the point of consumption alter incentives and generate an inefficient allocation of scarce resources?
  2. b) Management is considering two reforms:
  • Measure 1: Reduce the fixed monthly fee and charge for each dish individually according to its actual cost.

  • Measure 2: Charge a deposit of $2.00\text{ \$}$ when picking up the tray, refundable only if it is returned with no leftover food.

Predict the incentives and possible perverse effects of each measure, and justify which one you would choose to minimize waste with the lowest management cost.

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Allocation mechanisms in the face of scarcity

Comparison of the mechanisms for allocating scarce resources: market price, first come first served, lottery and administrative criterion. Price: whoever values it most pays First come, first served: first to ask Lottery: equal probability Administrative criterion: income, urgency

Back to the Friday-night snack bar: at $\$4$ the 180-hot-dog shortage remains, so someone goes without. The school can raise the price until the quantity demanded falls to 120, or it can keep the price and choose who goes without with a line (first come, first served) or a raffle.

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A nonprofit receives $500$ packs of school supplies to distribute among $800$ families that have applied. Analyze four ways of handing them out (selling them at a low…

A nonprofit receives $500$ packs of school supplies to distribute among $800$ families that have applied. Analyze four ways of handing them out (selling them at a low price, first come first served, a lottery, an income-based criterion) and explain what problem and what advantage each rationing mechanism has.

Solve
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A local district hospital has $3$ daily shifts for non-urgent MRI scans and receives an average of $10$ requests per day, resulting in a four-month waiting list. The…

A local district hospital has $3$ daily shifts for non-urgent MRI scans and receives an average of $10$ requests per day, resulting in a four-month waiting list. The management team is debating two proposals to manage scarcity:

  • Proposal A: Introduce a deterrent co-payment of $60.00\text{ \$}$ per scan to eliminate requests with lower clinical need.

  • Proposal B: Allocate shifts using clinical triage based on objective points and penalize anyone who does not attend their booked appointment with the loss of their turn.

  1. a) Analyze Proposal A by distinguishing between «effective demand» and «real need»: why does rationing a healthcare service solely by price lead to a loss of social efficiency even if it reduces the waiting list?
  2. b) In Proposal B, identify the opportunity cost borne by patients while waiting and design an improvement to this system that prevents empty slots from going unfilled without using price as a barrier to access.
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A city council organizes a free concert in a square with room for $5,000$ people and $20,000$ sign up. a) Is the concert a free good? Justify your answer. b) What…

A city council organizes a free concert in a square with room for $5,000$ people and $20,000$ sign up.

  1. a) Is the concert a free good? Justify your answer.
  2. b) What allocation mechanisms can be used when there is not enough room? Name two and comment on their effects.
Solve

Summary

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A nonprofit receives $500$ packs of school supplies to distribute among $800$ families that have applied. Analyze four ways of handing them out (selling them at a low…

A nonprofit receives $500$ packs of school supplies to distribute among $800$ families that have applied. Analyze four ways of handing them out (selling them at a low price, first come first served, a lottery, an income-based criterion) and explain what problem and what advantage each rationing mechanism has.

Solve
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