Chapter 16: Information, Risk, and Insurance
Every purchase rests on a belief about quality — but what happens when buyers and sellers have unequal or incomplete information? This chapter explores how imperfect and asymmetric information affect goods, labor, and financial capital markets, the mechanisms that help bridge information gaps, and how insurance markets grapple with moral hazard and adverse selection.
Table of Contents
1. Imperfect Information and Asymmetric Information
Imperfect information: A situation where either the buyer, the seller, or both are less than 100% certain about the qualities of what they are buying and selling.
Asymmetric information: A situation where one party (buyer or seller) has more information than the other about the product’s quality or price.
1.1 The “Lemons” Problem
Emerald example: Celebrity psychologist Doree Lynn bought a $14,500 emerald in 1994. Years later it fractured — cracks had been filled with epoxy resin without disclosure. Most emeralds have internal flaws and are soaked in clear oil or epoxy to hide them. This is legal if disclosed, but sellers often fail to disclose. NBC’s “Dateline” (1997) tested emeralds from four prominent NYC jewelers — all were treated, despite sales clerks claiming otherwise.
Used car market (“lemons”): A buyer (Marvin) cannot be certain whether a used car is a “lemon” (a defective product). Two similar-looking cars may differ greatly in hidden quality. The seller knows more about problems than the buyer — an asymmetric information problem.
Key insight — price reflects information:
- Higher-priced dealers invest in reputation → they fix hidden problems to maintain trust
- Cheaper lots and private sales (e.g., Craigslist) carry more risk with less reputation at stake
- Buyers must balance risk appetite against potential repair costs
1.2 Imperfect Information in Labor and Capital Markets
| Market | “Lemon” Problem | Information Mechanisms |
|---|---|---|
| Goods | Hidden product defects | Money-back guarantees, warranties, service contracts, reputation |
| Labor | Poor-quality employees | Resumes, references, degrees, occupational licenses, trial periods |
| Financial capital | Borrower default risk | Loan applications, credit checks, cosigners, collateral |
1.3 When Price Mixes with Imperfect Information
Buyers often use price as a signal of quality: expensive restaurant → food must be good; $400/hour lawyer → must be better than $150/hour lawyer.
Counter-intuitive effect: When buyers equate price with quality, lowering prices can reduce quantity demanded (buyers think the product is low quality), and raising prices can increase quantity demanded. This contradicts the basic demand curve — but reaches natural limits as information becomes more widely known.
1.4 Behavioral Economics: “Irrational” Behavior
Behavioral economists (Daniel Kahneman & Amos Tversky, 1979 Econometrica) challenged the assumption of perfect rationality:
- Loss aversion: A $1 loss pains us 2.25 times more than a $1 gain helps us — people “overplay” the stock market by reacting more to losses
- Framing effect: You’d walk 5 minutes to save $10 on a $20 alarm clock, but not to save $10 on a $300 phone — even though “$10 is $10”
- People evaluate outcomes relative to a reference point and think in percentages rather than absolutes
1.5 Mechanisms to Reduce Risk from Imperfect Information
Goods Markets
| Mechanism | How It Works |
|---|---|
| Money-back guarantee | Promise to refund if unsatisfied (L.L. Bean: guaranteed satisfaction since 1911; 90 of first 100 hunting shoes returned — all replaced) |
| Warranty | Promise to fix or replace for a set time period |
| Service contract | Buyer pays extra; seller agrees to fix anything specified for a set period |
| Reputation | Established firms charge more but carry less risk; repeat customers and word-of-mouth create long-term value |
Labor Markets
- Occupational licenses: Government-issued licenses confirming education or testing (doctors, lawyers, teachers, nurses, engineers, barbers, real estate brokers, etc.)
- According to a 2013 University of Chicago study, about 29% of U.S. workers have jobs requiring occupational licenses
Downside of occupational licenses: They represent a barrier to entry — making it harder for new entrants to compete, which can lead to higher prices and less consumer choice.
Financial Capital Markets
- Cosigner: Another person legally pledges to repay if the original borrower defaults
- Collateral: Property or equipment the bank can seize and sell if the borrower doesn’t repay
- Credit checks: Review of past borrowing history
1.6 Advertising and Imperfect Information
The Federal Trade Commission (FTC) enforces advertising rules:
- Exaggeration about general enjoyment is allowed
- Factual claims must be true
| Case | What Happened |
|---|---|
| Colgate-Palmolive (1950s) | TV ad showed “sandpaper” shaving — actually sand sprinkled on Plexiglas |
| Campbell’s Soup (1960s) | Filled bowl with marbles so vegetables appeared plentiful |
| Volvo (late 1980s) | Monster truck ad — Volvo’s roof was secretly reinforced with extra steel |
| Wonder Bread (2002) | “Professor Wonder” claimed extra calcium improved children’s memory — FTC stopped the ads |
Latin saying: Caveat emptor — “let the buyer beware.”
2. Insurance and Imperfect Information
Insurance: A method of protecting against financial loss. Policyholders make regular premium payments into a pool; those who suffer specified adverse events receive payments from the pool.
2.1 Types of Insurance
| Type | Who Pays | Pays Out When… |
|---|---|---|
| Health insurance | Employers & individuals | Medical expenses incurred |
| Life insurance | Employers & individuals | Policyholder dies |
| Auto insurance | Individuals | Car damaged, stolen, or causes damage |
| Property / homeowner’s | Homeowners & renters | Dwelling damaged or burglarized |
| Liability insurance | Firms & individuals | Injury for which you are partly responsible |
| Malpractice insurance | Doctors, lawyers, professionals | Poor service causes harm |
2.2 How Insurance Works
Auto insurance example — 100 drivers:
| Group | # Drivers | Damage per Driver | Total |
|---|---|---|---|
| Low risk (dings, chips) | 60 | $100 | $6,000 |
| Medium risk (moderate accidents) | 30 | $1,000 | $30,000 |
| High risk (major accidents) | 10 | $15,000 | $150,000 |
| Total | 100 | $186,000 |
If each driver pays a $1,860 premium, the insurance company collects exactly enough to cover all claims.
Actuarially Fair Premium — Formula & Worked Example
The actuarially fair premium for any risk group is:
\[P_{\text{fair}} = \sum_{i} p_i \times L_i\]where $p_i$ is the probability of event $i$ and $L_i$ is the loss from event $i$.
Application to the 100-driver pool:
\[P_{\text{pool}} = 0.60 \times \$100 + 0.30 \times \$1{,}000 + 0.10 \times \$15{,}000\] \[= \$60 + \$300 + \$1{,}500 = \$1{,}860\]Expected value for each risk group:
| Group | Premium Paid | Expected Loss | Net Cost of Insurance |
|---|---|---|---|
| Low-risk | $1,860 | $100 | −$1,760 (overpays) |
| Medium-risk | $1,860 | $1,000 | −$860 (overpays) |
| High-risk | $1,860 | $15,000 | +$13,140 (huge gain) |
This cross-subsidization is why low-risk drivers drop out → triggering adverse selection.
Fundamental law of insurance: The average person’s payments over time must cover (1) the average person’s claims, (2) administrative costs, and (3) the firm’s profits.
Insurance company income sources:
- Premiums from policyholders
- Investment income from reserves (funds collected but not yet paid as claims)
2.3 Government and Social Insurance
| Program | How It Works |
|---|---|
| Unemployment insurance | Employers pay into a fund; benefits go to workers who lose jobs (usually up to 6 months) |
| Pension insurance (PBGC) | Employers pay into the Pension Benefit Guarantee Corporation; it pays pensions if a company goes bankrupt |
| Deposit insurance (FDIC) | Banks pay into the Federal Deposit Insurance Corporation; protects deposits up to $250,000 (raised from $100K in 2008) |
| Workers’ compensation | Employers pay into state-level funds; benefits go to workers injured on the job |
| Social Security & Medicare | Workers pay a percentage of income; provides income and healthcare benefits to the elderly (“social insurance”) |
2.4 Risk Groups and Actuarial Fairness
Risk group: A group sharing roughly the same risks of an adverse event.
Actuarially fair insurance: When premiums equal the average expected losses for that risk group.
In the 100-driver example, if the company can classify drivers:
- Low-risk: $100 premium (actuarially fair)
- Medium-risk: $1,000 premium
- High-risk: $15,000 premium
Without classification, low-risk drivers subsidize high-risk drivers through a blended $1,860 premium.
2.5 Moral Hazard
Moral hazard: When insured people engage in riskier behavior than they would without insurance, because they don’t bear the full cost of their actions.
Examples:
- Health insurance → less effort to prevent illness
- Car insurance → less careful driving or parking
- Business insurance → installing only minimum security instead of top-level systems
Methods to reduce moral hazard:
| Method | How It Works |
|---|---|
| Deductible | Policyholder pays the first $X out of pocket (e.g., auto insurance covers losses > $500) |
| Copayment | Flat fee per service (e.g., $20 per doctor visit) |
| Coinsurance | Policyholder pays a percentage of costs (e.g., 20% of home repair after fire) |
| Fraud investigation | Insurance companies investigate suspicious claims |
| Monitoring behavior | Lower rates for businesses with top-level security systems |
Research finding: People facing moderate deductibles and copayments consume about one-third less medical care than people with complete insurance — with no measurable difference in health outcomes. This suggests that full insurance generates substantial moral hazard.
Healthcare delivery models:
| Model | Payment | Moral Hazard Incentive |
|---|---|---|
| Fee-for-service | Providers paid per service rendered | Providers incentivized to deliver more services |
| HMO (Health Maintenance Organization) | Providers receive a fixed amount per enrolled person | Providers incentivized to limit unnecessary services |
2.6 Adverse Selection
Adverse selection: When insurance buyers know more about their own risks than the insurance company. High-risk individuals are attracted to insurance, while low-risk individuals are priced out — potentially strangling the market.
How adverse selection destroys a market:
Using the 100-driver example: the company charges $1,860 (average).
- Low-risk drivers (expected loss $100) → won’t pay $1,860 → drop out
- Medium-risk drivers (expected loss $1,000) → won’t pay $1,860 → drop out
- Only high-risk drivers (expected loss $15,000) remain → company loses massively at $1,860/policy
- If company raises premiums → even more low/medium-risk drivers exit → death spiral
Solutions to adverse selection:
- Classify buyers into risk groups and charge accordingly (but may exclude high-risk individuals)
- Mandate insurance purchase so low-risk individuals remain in the pool
2.7 U.S. Healthcare in International Context
| Country | Spending/Person | Male Life Expectancy | Female Life Expectancy | Infant Mortality (per 1,000) |
|---|---|---|---|---|
| United States | $10,948 | 75.5 | 80.2 | 5.7 |
| Germany | $6,731 | 79.0 | 83.7 | 3.2 |
| France | $5,564 | 79.2 | 85.3 | 3.5 |
| Canada | $5,370 | 80.0 | 84.2 | 4.4 |
| United Kingdom | $5,268 | 78.4 | 82.4 | 3.7 |
Key paradox: The U.S. spends far more per person on healthcare than any comparable nation, yet has worse health outcomes (lower life expectancy, higher infant mortality). Studies show health is more closely related to diet, exercise, and genetics than to healthcare expenditure.
2.8 Government Regulation of Insurance
- U.S. insurance is primarily regulated at the state level (National Association of Insurance Commissioners since 1871)
- Regulators try to (1) keep premiums low and (2) ensure everyone has insurance — but these goals can conflict
- If states force premiums below actuarially fair levels, insurance companies may withdraw from the state (e.g., 20+ companies left New Jersey in late 1990s/early 2000s; State Farm left Florida property insurance in 2009)
2.9 The Patient Protection and Affordable Care Act (ACA / “Obamacare”)
Signed by President Obama in March 2010, phased in starting October 2013.
Key provisions:
| Feature | Purpose |
|---|---|
| Individual mandate | All individuals must have insurance or pay a fine → reduces adverse selection by keeping low-risk people in the pool (fine eliminated in 2019) |
| Health insurance exchanges | States create marketplaces where insurers compete → improves competition, lowers prices |
| Employer mandate | Employers with 50+ employees must offer health insurance |
| Pre-existing conditions | Insurers cannot deny coverage based on pre-existing conditions |
Funding sources:
- Medicare tax increase of 0.9% + 3.8% tax on unearned income for high earners
- Annual fee on health insurance providers
- 2.3% tax on medical device manufacturers/importers
Results:
- Uninsured rate fell from 20.3% (2012) → 11.5% (2016) → 8.6% (2020)
- ~20 million Americans gained coverage
- CBO estimates the ACA will increase federal debt by $137 billion over a decade
3. Key Takeaways
- Imperfect information (neither party has full knowledge) and asymmetric information (one party knows more) can prevent markets from reaching efficient equilibria
- The “lemons” problem arises when sellers know more about quality than buyers — mechanisms like guarantees, warranties, reputation, and licenses help bridge the gap
- Behavioral economics (Kahneman & Tversky) shows systematic “irrational” behavior: loss aversion (losses hurt 2.25× more than equivalent gains) and framing effects
- Insurance pools risk: the fundamental law is that average premiums must cover average claims + costs + profits
- Moral hazard (riskier behavior when insured) is reduced by deductibles, copayments, coinsurance, and HMO structures
- Adverse selection (high-risk buyers seek insurance, low-risk drop out) can create a “death spiral” — solved by risk classification or mandatory insurance
- The U.S. spends far more on healthcare than comparable nations but with worse outcomes; the ACA (2010) reduced the uninsured rate by nearly 60%
4. Practice Questions
Q1. What is the difference between imperfect information and asymmetric information?
Answer
Imperfect information means both buyer and seller lack complete knowledge about the product's quality or price. Asymmetric information means one party has significantly more information than the other. Asymmetric information is a specific type of imperfect information.Q2. A used car dealer cuts prices to clear inventory, but sales actually decline. Explain this using the concept of imperfect information.
Answer
When buyers use price as a signal of quality, a lower price may signal that the cars are lower quality ("lemons"), making buyers less willing to purchase. This runs counter to the standard demand curve but is explained by buyers' inability to independently assess quality.Q3. Rank these purchases from lowest to highest degree of imperfect information: (a) buying apples at a roadside stand, (b) buying a used laptop at a garage sale, (c) ordering flowers online for a friend in another city.
Answer
(a) Apples — lowest (you can see and touch them). (b) Used laptop — high (hidden mechanical/software issues). (c) Online flowers — highest (you can't see the product, the seller is distant, and the recipient is in another city). However, (b) and (c) are both high — the laptop arguably has more at stake financially.Q4. In the auto insurance example with 100 drivers, what is the actuarially fair premium for each risk group?
Answer
Low-risk (60 drivers): $100 per driver. Medium-risk (30 drivers): $1,000 per driver. High-risk (10 drivers): $15,000 per driver. These match each group's expected losses exactly.Q5. How does a deductible reduce moral hazard? Give an example.
Answer
A deductible requires the policyholder to pay the first portion of any claim out of pocket. For example, a $500 auto insurance deductible means the driver bears the first $500 of any damage. This gives the driver a financial incentive to drive carefully, because they will pay for at least some of the cost of any accident.Q6. Explain the “death spiral” of adverse selection in an insurance market.
Answer
When an insurer charges average premiums, low-risk individuals (whose expected costs are much lower) find the price too high and drop out. This raises the average risk (and cost) of the remaining pool, forcing higher premiums. This drives out medium-risk buyers, leaving only high-risk buyers at premiums far below their actual costs. The insurer either raises prices further (losing more customers) or exits the market entirely.Q7. How does the ACA’s individual mandate address the adverse selection problem?
Answer
By requiring all individuals to purchase insurance (or pay a penalty), the mandate ensures that low-risk, healthy people remain in the insurance pool. This prevents adverse selection because the insurer's pool includes a mix of risk levels, allowing premiums to remain affordable for everyone.Q8. Loss aversion means a $1 loss pains us 2.25× more than a $1 gain. How might this affect stock market behavior?
Answer
Investors tend to react more strongly to stock market losses than to equivalent gains. This can cause people to sell stocks after a decline (to avoid further losses) and hold stocks too long during gains (hoping for more). It leads to overreaction during downturns and contributes to market volatility.Q9. The U.S. spends over $10,000 per person on healthcare — nearly double Germany’s spending. Yet U.S. life expectancy is lower. Why doesn’t more spending lead to better outcomes?
Answer
Health outcomes are more closely related to diet, exercise, and genetic factors than to healthcare expenditure. The U.S. system, driven by fee-for-service and moral hazard, encourages overuse of expensive treatments. Additionally, unequal access (31 million uninsured as of 2020) means critical populations receive suboptimal preventive care.Q10. What is the difference between fee-for-service and HMO models, and how does each affect moral hazard?
Answer
Fee-for-service pays providers per service rendered — creating incentives for providers to deliver more services (increasing moral hazard). HMOs pay a fixed amount per enrolled person regardless of services provided — giving providers an incentive to limit unnecessary care (reducing moral hazard from the provider side).Q11. Why might an insurance company withdraw from a state that requires low premiums?
Answer
If regulators force premiums below actuarially fair levels, the insurer's claims will exceed premium revenue over time, causing financial losses. The company cannot sustain losses indefinitely and may choose to stop doing business in that state rather than go bankrupt. Over 20 insurers left New Jersey for this reason.Q12. How do occupational licenses both help and hurt consumers?
Answer
**Help:** They signal that a worker has met minimum education or testing standards, reducing imperfect information and protecting consumers from unqualified practitioners. **Hurt:** They act as barriers to entry, reducing competition, limiting consumer choice, and potentially raising prices. About 29% of U.S. workers need occupational licenses.Q13. An insurance company pools 200 homeowners. 150 have a 2% chance of a $50,000 fire loss, and 50 have a 10% chance of a $50,000 loss. (a) Calculate the actuarially fair premium for each group. (b) Calculate the blended pool premium. (c) Explain the adverse selection risk.
Answer
**(a)** Low-risk: $P = 0.02 \times \$50{,}000 = \$1{,}000$. High-risk: $P = 0.10 \times \$50{,}000 = \$5{,}000$. **(b)** Total expected claims = $(150 \times \$1{,}000) + (50 \times \$5{,}000) = \$150{,}000 + \$250{,}000 = \$400{,}000$. Blended premium = $\$400{,}000 / 200 = \$2{,}000$. **(c)** Low-risk homeowners face a premium ($2,000) that is double their expected loss ($1,000). Many will drop coverage. As they exit, the remaining pool becomes riskier, premiums must rise, and the death spiral begins.Q14. A health insurance plan has a $500 deductible and 20% coinsurance. If a patient incurs $8,000 in medical bills, how much does (a) the patient pay and (b) the insurer pay? (c) How does this structure reduce moral hazard?
Answer
**(a)** Patient pays: deductible ($500) + 20% of remaining ($8,000 − $500 = $7,500 × 0.20 = $1,500) = **$2,000**. **(b)** Insurer pays: $7,500 × 0.80 = **$6,000**. **(c)** The patient bears $2,000 of the $8,000 cost (25%), giving them a financial incentive to avoid unnecessary care, seek lower-cost providers, and maintain healthy behaviors. Without cost-sharing, the patient would consume more care with zero marginal cost.Q15. In 2019, the ACA’s individual mandate penalty was reduced to $0. Predict the effect on adverse selection in the insurance market, and explain whether other ACA provisions (exchanges, pre-existing condition protections) can substitute for the mandate.
Answer
Without the mandate penalty, healthy low-risk individuals have less incentive to buy insurance, potentially triggering adverse selection. The pre-existing condition rule worsens this: people can wait until they're sick to buy insurance (called "guaranteed issue" without mandate creates a free-rider problem). Exchanges alone don't solve the problem — they lower *search costs* but don't force participation. Subsidies partially substitute by making insurance cheaper for low/middle-income healthy individuals, but the risk of a death spiral increases without a mandate or equivalent mechanism (like continuous-coverage incentives).5. Glossary
| Term | Definition |
|---|---|
| Imperfect information | Buyer and/or seller lack full knowledge about a product’s quality or price |
| Asymmetric information | One party has more information than the other in a transaction |
| “Lemon” | A product (especially a car) that turns out to have low quality after purchase |
| Money-back guarantee | Seller’s promise to refund the buyer’s money under certain conditions |
| Warranty | Promise to fix or replace a good for a set time period |
| Service contract | Buyer pays extra; seller agrees to fix specified issues for a set period |
| Occupational license | Government-issued certification that a worker has completed required education or testing |
| Insurance | Method of pooling risk; policyholders pay premiums, and those suffering adverse events receive compensation |
| Premium | Regular payment made to an insurance company |
| Risk group | A group sharing roughly the same risk of an adverse event |
| Actuarially fair | When premiums equal the average expected losses for a risk group |
| Moral hazard | Insured people behave more riskily because they don’t bear the full cost |
| Adverse selection | Higher-risk individuals disproportionately seek insurance, driving up costs |
| Deductible | Amount the policyholder pays out of pocket before insurance coverage kicks in |
| Copayment | Flat fee paid per service before insurance covers the rest |
| Coinsurance | Policyholder pays a percentage of total costs |
| Fee-for-service | Providers paid per service rendered |
| HMO | Health Maintenance Organization — providers receive a fixed amount per enrollee |
| Cosigner | Person who legally pledges to repay a loan if the original borrower defaults |
| Collateral | Valuable asset pledged as security for a loan |