The kremerian model on population growth

Macro Econonomics.

MACROECONOMICS

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N. GREGORY MANKIW Harvard University

Worth Publishers

EIGHTH EDITION

MACROECONOMICS

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Senior Vice President, Editorial and Production: Catherine Woods

Publisher: Charles Linsmeier

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Composition: MPS Limited

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Cover Art: Jylian Gustlin, Fibonacci 48

Library of Congress Control Number: 2012933861

ISBN-13: 978-1-4292-4002-4

ISBN-10: 1-4292-4002-4

© 2013, 2010, 2007, 2003 by Worth Publishers

All rights reserved.

Printed in the United States of America

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http://www.worthpublishers.com
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about the author

P h

o to

b y

Jo rd

i C

ab ré

N. Gregory Mankiw is the Robert M. Beren Professor of Economics at

Harvard University. He began his study of economics at Princeton University,

where he received an A.B. in 1980. After earning a Ph.D. in economics from

MIT, he began teaching at Harvard in 1985 and was promoted to full professor

in 1987. Today, he regularly teaches both undergraduate and graduate courses

in macroeconomics. He is also author of the best-selling introductory textbook

Principles of Economics (Cengage Learning).

Professor Mankiw is a regular participant in academic and policy debates. His

research ranges across macroeconomics and includes work on price adjustment,

consumer behavior, financial markets, monetary and fiscal policy, and economic

growth. In addition to his duties at Harvard, he has been a research associate of

the National Bureau of Economic Research, a member of the Brookings Panel

on Economic Activity, and an adviser to Congressional Budget Office and the

Federal Reserve Banks of Boston and New York. From 2003 to 2005 he was

chairman of the President’s Council of Economic Advisers.

Professor Mankiw lives in Wellesley, Massachusetts, with his wife, Deborah;

children, Catherine, Nicholas, and Peter; and their border terrier, Tobin.

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To Deborah

Mankiw_Macro_FM.indd viMankiw_Macro_FM.indd vi 04/19/12 6:47 PM04/19/12 6:47 PM

Those branches of politics, or of the laws of social life, on which there exists a collection of facts sufficiently sifted and methodized to form the beginning of a science should be taught ex professo. Among the chief of these is Political Economy, the sources and conditions of wealth and

material prosperity for aggregate bodies of human beings. . . .

The same persons who cry down Logic will generally warn you against

Political Economy. It is unfeeling, they will tell you. It recognises unpleasant

facts. For my part, the most unfeeling thing I know of is the law of gravitation:

it breaks the neck of the best and most amiable person without scruple, if he

forgets for a single moment to give heed to it. The winds and waves too are very

unfeeling. Would you advise those who go to sea to deny the winds and waves –

or to make use of them, and find the means of guarding against their dangers?

My advice to you is to study the great writers on Political Economy, and hold

firmly by whatever in them you find true; and depend upon it that if you are not

selfish or hardhearted already, Political Economy will not make you so.

John Stuart Mill, 1867

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viii |

Preface xxiii Supplements and Media xxxii

part I Introduction 1 Chapter 1 The Science of Macroeconomics 3 Chapter 2 The Data of Macroeconomics 17

part II Classical Theory: The Economy in the Long Run 45 Chapter 3 National Income: Where It Comes

From and Where It Goes 47

Chapter 4 The Monetary System: What It Is and How It Works 81

Chapter 5 Inflation: Its Causes, Effects, and Social Costs 101

Chapter 6 The Open Economy 133 Chapter 7 Unemployment 177

part III Growth Theory: The Economy in the Very Long Run 203 Chapter 8 Economic Growth I: Capital

Accumulation and Population Growth 205

Chapter 9 Economic Growth II: Technology, Empirics, and Policy 235

part IV Business Cycle Theory: The Economy in the Short Run 271 Chapter 10 Introduction to Economic

Fluctuations 273

Chapter 11 Aggregate Demand I: Building the IS–LM Model 303

Chapter 12 Aggregate Demand II: Applying the IS–LM Model 327

Chapter 13 The Open Economy Revisited: The Mundell–Fleming Model and the Exchange-Rate Regime 355

Chapter 14 Aggregate Supply and the Short- Run Tradeoff Between Inflation and Unemployment 397

part V Topics in Macroeconomic Theory 427 Chapter 15 A Dynamic Model of Aggregate

Demand and Aggregate Supply 429

Chapter 16 Understanding Consumer Behavior 465

Chapter 17 The Theory of Investment 497

part VI Topics in Macroeconomic Policy 519 Chapter 18 Alternative Perspectives on

Stabilization Policy 521

Chapter 19 Government Debt and Budget Deficits 543

Chapter 20 The Financial System: Opportunities and Dangers 569

Epilogue What We Know, What We Don’t 593

Glossary 601 Index 611

brief contents

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| ix

Preface xxiii Supplements and Media xxxii

part I Introduction 1

Chapter 1 The Science of Macroeconomics 3

1-1 What Macroeconomists Study 3 � CASE STUDY The Historical Performance of the U.S. Economy 5

1-2 How Economists Think 7 Theory as Model Building 8

� FYI Using Functions to Express Relationships Among Variables 11 The Use of Multiple Models 12

Prices: Flexible Versus Sticky 12

Microeconomic Thinking and Macroeconomic Models 13

� FYI Nobel Macroeconomists 14

1-3 How This Book Proceeds 15

Chapter 2 The Data of Macroeconomics 17

2-1 Measuring the Value of Economic Activity: Gross Domestic Product 18 Income, Expenditure, and the Circular Flow 18

� FYI Stocks and Flows 20 Rules for Computing GDP 20

Real GDP Versus Nominal GDP 23

The GDP Deflator 25

Chain-Weighted Measures of Real GDP 25

� FYI Two Arithmetic Tricks for Working With Percentage Changes 26 The Components of Expenditure 27

� FYI What Is Investment? 28 � CASE STUDY GDP and Its Components 28 Other Measures of Income 29

Seasonal Adjustment 31

2-2 Measuring the Cost of Living: The Consumer Price Index 32 The Price of a Basket of Goods 32

The CPI Versus the GDP Deflator 33

Does the CPI Overstate Inflation? 35

� CASE STUDY The Billion Prices Project 36

contents

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2-3 Measuring Joblessness: The Unemployment Rate 36 The Household Survey 37

� CASE STUDY Trends in Labor-Force Participation 38 The Establishment Survey 40

2-4 Conclusion: From Economic Statistics to Economic Models 41

part II Classical Theory: The Economy in the Long Run 45

Chapter 3 National Income: Where It Comes From and Where It Goes 47

3-1 What Determines the Total Production of Goods and Services? 49 The Factors of Production 49

The Production Function 50

The Supply of Goods and Services 50

3-2 How Is National Income Distributed to the Factors of Production? 51 Factor Prices 51

The Decisions Facing a Competitive Firm 52

The Firm’s Demand for Factors 53

The Division of National Income 56

� CASE STUDY The Black Death and Factor Prices 58 The Cobb—Douglas Production Function 58

� FYI The Growing Gap Between Rich and Poor 62 � CASE STUDY Labor Productivity as the Key Determinant of Real Wages 62

3-3 What Determines the Demand for Goods and Services? 63 Consumption 64

Investment 65

� FYI The Many Different Interest Rates 67 Government Purchases 67

3-4 What Brings the Supply and Demand for Goods and Services Into Equilibrium? 68 Equilibrium in the Market for Goods and Services: The Supply and Demand

for the Economy’s Output 69

Equilibrium in the Financial Markets: The Supply and Demand for Loanable Funds 70

Changes in Saving: The Effects of Fiscal Policy 72

� CASE STUDY Wars and Interest Rates in the United Kingdom, 1730–1920 73 Changes in Investment Demand 74

3-5 Conclusion 76

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Chapter 4 The Monetary System: What It Is and How It Works 81

4-1 What Is Money? 81 The Functions of Money 82

The Types of Money 82

� CASE STUDY Money in a POW Camp 83 The Development of Fiat Money 84

� CASE STUDY Money and Social Conventions on the Island of Yap 84 How the Quantity of Money Is Controlled 85

How the Quantity of Money Is Measured 85

� FYI How Do Credit Cards and Debit Cards Fit Into the Monetary System? 87

4-2 The Role of Banks in the Monetary System 87 100-Percent-Reserve Banking 88

Fractional-Reserve Banking 88

Bank Capital, Leverage, and Capital Requirements 90

4-3 How Central Banks Influence the Money Supply 92 A Model of the Money Supply 92

The Instruments of Monetary Policy 94

� CASE STUDY Quantitative Easing and the Exploding Monetary Base 95 Problems in Monetary Control 96

� CASE STUDY Bank Failures and the Money Supply in the 1930s 97

4-4 Conclusion 98

Chapter 5 Inflation: Its Causes, Effects, and Social Costs 101

5-1 The Quantity Theory of Money 102 Transactions and the Quantity Equation 102

From Transactions to Income 103

The Money Demand Function and the Quantity Equation 104

The Assumption of Constant Velocity 105

Money, Prices, and Inflation 106

� CASE STUDY Inflation and Money Growth 106

5-2 Seigniorage: The Revenue From Printing Money 109 � CASE STUDY Paying for the American Revolution 109

5-3 Inflation and Interest Rates 110 Two Interest Rates: Real and Nominal 110

The Fisher Effect 110

� CASE STUDY Inflation and Nominal Interest Rates 111 Two Real Interest Rates: Ex Ante and Ex Post 112

� CASE STUDY Nominal Interest Rates in the Nineteenth Century 113

5-4 The Nominal Interest Rate and the Demand for Money 114 The Cost of Holding Money 114

Future Money and Current Prices 114

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5-5 The Social Costs of Inflation 116 The Layman’s View and the Classical Response 116

� CASE STUDY What Economists and the Public Say About Inflation 117

The Costs of Expected Inflation 117

The Costs of Unexpected Inflation 119

� CASE STUDY The Free Silver Movement, the Election of 1896, and The Wizard of Oz 120

One Benefit of Inflation 121

5-6 Hyperinflation 121 The Costs of Hyperinflation 122

The Causes of Hyperinflation 122

� CASE STUDY Hyperinflation in Interwar Germany 123 � CASE STUDY Hyperinflation in Zimbabwe 125

5-7 Conclusion: The Classical Dichotomy 126 Appendix: The Cagan Model: How Current and Future Money Affect the Price Level 130

Chapter 6 The Open Economy 133

6-1 The International Flows of Capital and Goods 134 The Role of Net Exports 134

International Capital Flows and the Trade Balance 136

International Flows of Goods and Capital: An Example 138

� FYI The Irrelevance of Bilateral Trade Balances 139

6-2 Saving and Investment in a Small Open Economy 139 Capital Mobility and the World Interest Rate 139

Why Assume a Small Open Economy? 140

The Model 141

How Policies Influence the Trade Balance 142

Evaluating Economic Policy 144

� CASE STUDY The U.S. Trade Deficit 146 � CASE STUDY Why Doesn’t Capital Flow to Poor Countries? 148

6-3 Exchange Rates 149 Nominal and Real Exchange Rates 149

The Real Exchange Rate and the Trade Balance 151

The Determinants of the Real Exchange Rate 151

How Policies Influence the Real Exchange Rate 153

The Effects of Trade Policies 154

The Determinants of the Nominal Exchange Rate 156

� CASE STUDY Inflation and Nominal Exchange Rates 157 The Special Case of Purchasing-Power Parity 159

� CASE STUDY The Big Mac Around the World 160

6-4 Conclusion: The United States as a Large Open Economy 162 Appendix: The Large Open Economy 166

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Net Capital Outflow 166

The Model 168

Policies in the Large Open Economy 170

Conclusion 174

Chapter 7 Unemployment 177

7-1 Job Loss, Job Finding, and the Natural Rate of Unemployment 178 7-2 Job Search and Frictional Unemployment 180

Causes of Frictional Unemployment 181

Public Policy and Frictional Unemployment 181

� CASE STUDY Unemployment Insurance and the Rate of Job Finding 182

7-3 Real-Wage Rigidity and Structural Unemployment 183 Minimum-Wage Laws 184

� CASE STUDY The Characteristics of Minimum-Wage Workers 185 Unions and Collective Bargaining 186

Efficiency Wages 187

� CASE STUDY Henry Ford’s $5 Workday 188

7-4 Labor-Market Experience: The United States 189 The Duration of Unemployment 189

� CASE STUDY The Increase in U.S. Long-Term Unemployment and the Debate Over Unemployment Insurance 190

Variation in the Unemployment Rate Across Demographic Groups 192

Transitions Into and Out of the Labor Force 193

7-5 Labor-Market Experience: Europe 194 The Rise in European Unemployment 194

Unemployment Variation Within Europe 196

� CASE STUDY The Secrets to Happiness 197 The Rise of European Leisure 198

7-6 Conclusion 200

part III Growth Theory: The Economy in the Very Long Run 203

Chapter 8 Economic Growth I: Capital Accumulation and Population Growth 205

8-1 The Accumulation of Capital 206 The Supply and Demand for Goods 206

Growth in the Capital Stock and the Steady State 209

Approaching the Steady State: A Numerical Example 211

� CASE STUDY The Miracle of Japanese and German Growth 213 How Saving Affects Growth 214

� CASE STUDY Saving and Investment Around the World 215

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8-2 The Golden Rule Level of Capital 217 Comparing Steady States 217

Finding the Golden Rule Steady State: A Numerical Example 220

The Transition to the Golden Rule Steady State 222

8-3 Population Growth 224 The Steady State With Population Growth 225

The Effects of Population Growth 226

� CASE STUDY Population Growth Around the World 228 Alternative Perspectives on Population Growth 229

8-4 Conclusion 231

Chapter 9 Economic Growth II: Technology, Empirics, and Policy 235

9-1 Technological Progress in the Solow Model 236 The Efficiency of Labor 236

The Steady State With Technological Progress 237

The Effects of Technological Progress 238

9-2 From Growth Theory to Growth Empirics 239 Balanced Growth 239

Convergence 240

Factor Accumulation Versus Production Efficiency 241

� CASE STUDY Is Free Trade Good for Economic Growth? 242

9-3 Policies to Promote Growth 243 Evaluating the Rate of Saving 244

Changing the Rate of Saving 245

Allocating the Economy’s Investment 246

� CASE STUDY Industrial Policy in Practice 247 Establishing the Right Institutions 248

� CASE STUDY The Colonial Origins of Modern Institutions 249 Encouraging Technological Progress 250

� CASE STUDY The Worldwide Slowdown in Economic Growth 251

9-4 Beyond the Solow Model: Endogenous Growth Theory 253 The Basic Model 254

A Two-Sector Model 255

The Microeconomics of Research and Development 256

The Process of Creative Destruction 257

9-5 Conclusion 258 Appendix: Accounting for the Sources of Economic Growth 262 Increases in the Factors of Production 262

Technological Progress 264

The Sources of Growth in the United States 265

� CASE STUDY Growth in the East Asian Tigers 266 The Solow Residual in the Short Run 267

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part IV Business Cycle Theory: The Economy in the Short Run 271

Chapter 10 Introduction to Economic Fluctuations 273

10-1 The Facts About the Business Cycle 274 GDP and Its Components 274

Unemployment and Okun’s Law 277

Leading Economic Indicators 279

10-2 Time Horizons in Macroeconomics 281 How the Short Run and Long Run Differ 281

� CASE STUDY If You Want to Know Why Firms Have Sticky Prices, Ask Them 282 The Model of Aggregate Supply and Aggregate Demand 284

10-3 Aggregate Demand 285 The Quantity Equation as Aggregate Demand 285

Why the Aggregate Demand Curve Slopes Downward 286

Shifts in the Aggregate Demand Curve 287

10-4 Aggregate Supply 288 The Long Run: The Vertical Aggregate Supply Curve 288

The Short Run: The Horizontal Aggregate Supply Curve 290

From the Short Run to the Long Run 291

� CASE STUDY A Monetary Lesson From French History 293 � FYI David Hume on the Real Effects of Money 294

10-5 Stabilization Policy 294 Shocks to Aggregate Demand 295

Shocks to Aggregate Supply 296

� CASE STUDY How OPEC Helped Cause Stagflation in the 1970s and Euphoria in the 1980s 298

10-6 Conclusion 299

Chapter 11 Aggregate Demand I: Building the IS–LM Model 303

11-1 The Goods Market and the IS Curve 305 The Keynesian Cross 305

� CASE STUDY Cutting Taxes to Stimulate the Economy: The Kennedy and Bush Tax Cuts 312

� CASE STUDY Increasing Government Purchases to Stimulate the Economy: The Obama Spending Plan 313

The Interest Rate, Investment, and the IS Curve 314

How Fiscal Policy Shifts the IS Curve 316

11-2 The Money Market and the LM Curve 317 The Theory of Liquidity Preference 317

� CASE STUDY Does a Monetary Tightening Raise or Lower Interest Rates? 319 Income, Money Demand, and the LM Curve 320

How Monetary Policy Shifts the LM Curve 321

11-3 Conclusion: The Short-Run Equilibrium 322

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Chapter 12 Aggregate Demand II: Applying the IS–LM Model 327

12-1 Explaining Fluctuations With the IS–LM Model 328 How Fiscal Policy Shifts the IS Curve and Changes the Short-Run

Equilibrium 328

How Monetary Policy Shifts the LM Curve and Changes the Short-Run Equilibrium 329

The Interaction Between Monetary and Fiscal Policy 331

� CASE STUDY Policy Analysis With Macroeconometric Models 333 Shocks in the IS–LM Model 334

� CASE STUDY The U.S. Recession of 2001 335 What Is the Fed’s Policy Instrument—The Money Supply

or the Interest Rate? 336

12-2 IS–LM as a Theory of Aggregate Demand 337 From the IS–LM Model to the Aggregate Demand Curve 337

The IS–LM Model in the Short Run and Long Run 340

12-3 The Great Depression 342 The Spending Hypothesis: Shocks to the IS Curve 343

The Money Hypothesis: A Shock to the LM Curve 344

The Money Hypothesis Again: The Effects of Falling Prices 345

Could the Depression Happen Again? 347

� CASE STUDY The Financial Crisis and Economic Downturn of 2008 and 2009 348

� FYI The Liquidity Trap (Also Known as the Zero Lower Bound) 350

12-4 Conclusion 351

Chapter 13 The Open Economy Revisited: The Mundell–Fleming Model and the Exchange-Rate Regime 355

13-1 The Mundell–Fleming Model 357 The Key Assumption: Small Open Economy With Perfect Capital Mobility 357

The Goods Market and the IS* Curve 358

The Money Market and the LM* Curve 358

Putting the Pieces Together 360

13-2 The Small Open Economy Under Floating Exchange Rates 361 Fiscal Policy 362

Monetary Policy 363

Trade Policy 364

13-3 The Small Open Economy Under Fixed Exchange Rates 365 How a Fixed-Exchange-Rate System Works 366

� CASE STUDY The International Gold Standard 367 Fiscal Policy 368

Monetary Policy 368

� CASE STUDY Devaluation and the Recovery From the Great Depression 370

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Trade Policy 370

Policy in the Mundell–Fleming Model: A Summary 371

13-4 Interest Rate Differentials 372 Country Risk and Exchange-Rate Expectations 372

Differentials in the Mundell–Fleming Model 373

� CASE STUDY International Financial Crisis: Mexico 1994–1995 375 � CASE STUDY International Financial Crisis: Asia 1997–1998 376

13-5 Should Exchange Rates Be Floating or Fixed? 377 Pros and Cons of Different Exchange-Rate Systems 377

� CASE STUDY The Debate Over the Euro 378 Speculative Attacks, Currency Boards, and Dollarization 380

The Impossible Trinity 381

� CASE STUDY The Chinese Currency Controversy 382

13-6 From the Short Run to the Long Run: The Mundell–Fleming Model With a Changing Price Level 383

13-7 A Concluding Reminder 386 Appendix: A Short-Run Model of the Large Open Economy 390 Fiscal Policy 392

Monetary Policy 393

A Rule of Thumb 394

Chapter 14 Aggregate Supply and the Short-Run Tradeoff Between Inflation and Unemployment 397

14-1 The Basic Theory of Aggregate Supply 398 The Sticky-Price Model 399

An Alternative Theory: The Imperfect-Information Model 401

� CASE STUDY International Differences in the Aggregate Supply Curve 403 Implications 404

14-2 Inflation, Unemployment, and the Phillips Curve 406 Deriving the Phillips Curve From the Aggregate Supply Curve 406

� FYI The History of the Modern Phillips Curve 408 Adaptive Expectations and Inflation Inertia 408

Two Causes of Rising and Falling Inflation 409

� CASE STUDY Inflation and Unemployment in the United States 409 The Short-Run Tradeoff Between Inflation and Unemployment 412

� FYI How Precise Are Estimates of the Natural Rate of Unemployment? 413 Disinflation and the Sacrifice Ratio 414

Rational Expectations and the Possibility of Painless Disinflation 414

� CASE STUDY The Sacrifice Ratio in Practice 416 Hysteresis and the Challenge to the Natural-Rate Hypothesis 417

14-3 Conclusion 419 Appendix: The Mother of All Models 422

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part V Topics in Macroeconomic Theory 427

Chapter 15 A Dynamic Model of Aggregate Demand and Aggregate Supply 429

15-1 Elements of the Model 430 Output: The Demand for Goods and Services 430

The Real Interest Rate: The Fisher Equation 431

Inflation: The Phillips Curve 432

Expected Inflation: Adaptive Expectations 433

The Nominal Interest Rate: The Monetary-Policy Rule 434

� CASE STUDY The Taylor Rule 435

15-2 Solving the Model 437 The Long-Run Equilibrium 437

The Dynamic Aggregate Supply Curve 439

The Dynamic Aggregate Demand Curve 440

The Short-Run Equilibrium 442

15-3 Using the Model 443 Long-Run Growth 444

A Shock to Aggregate Supply 444

� FYI The Numerical Calibration and Simulation 447 A Shock to Aggregate Demand 448

A Shift in Monetary Policy 449

15-4 Two Applications: Lessons for Monetary Policy 453 The Tradeoff Between Output Variability and Inflation

Variability 453

� CASE STUDY The Fed Versus the European Central Bank 455 The Taylor Principle 456

� CASE STUDY What Caused the Great Inflation? 459

15-5 Conclusion: Toward DSGE Models 460

Chapter 16 Understanding Consumer Behavior 465

16-1 John Maynard Keynes and the Consumption Function 466 Keynes’s Conjectures 466

The Early Empirical Successes 467

Secular Stagnation, Simon Kuznets, and the Consumption Puzzle 468

16-2 Irving Fisher and Intertemporal Choice 470 The Intertemporal Budget Constraint 470

� FYI Present Value, or Why a $1,000,000 Prize Is Worth Only $623,000 472 Consumer Preferences 473

Optimization 474

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How Changes in Income Affect Consumption 475

How Changes in the Real Interest Rate Affect Consumption 476

Constraints on Borrowing 477

16-3 Franco Modigliani and the Life-Cycle Hypothesis 479 The Hypothesis 480

Implications 481

� CASE STUDY The Consumption and Saving of the Elderly 483

16-4 Milton Friedman and the Permanent-Income Hypothesis 484 The Hypothesis 484

Implications 485

� CASE STUDY The 1964 Tax Cut and the 1968 Tax Surcharge 486 � CASE STUDY The Tax Rebates of 2008 486

16-5 Robert Hall and the Random-Walk Hypothesis 487 The Hypothesis 488

Implications 488

� CASE STUDY Do Predictable Changes in Income Lead to Predictable Changes in Consumption? 489

16-6 David Laibson and the Pull of Instant Gratification 490 � CASE STUDY How to Get People to Save More 491

16-7 Conclusion 492

Chapter 17 The Theory of Investment 497

17-1 Business Fixed Investment 498 The Rental Price of Capital 499

The Cost of Capital 500

The Determinants of Investment 502

Taxes and Investment 504

The Stock Market and Tobin’s q 505

� CASE STUDY The Stock Market as an Economic Indicator 506 Alternative Views of the Stock Market: The Efficient Markets Hypothesis Versus

Keynes’s Beauty Contest 507

Financing Constraints 509

17-2 Residential Investment 510 The Stock Equilibrium and the Flow Supply 510

Changes in Housing Demand 511

17-3 Inventory Investment 514 Reasons for Holding Inventories 514

How the Real Interest Rate and Credit Conditions Affect Inventory Investment 515

17-4 Conclusion 515

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part VI Topics in Macroeconomic Policy 519

Chapter 18 Alternative Perspectives on Stabilization Policy 521

18-1 Should Policy Be Active or Passive? 522 Lags in the Implementation and Effects of Policies 522

The Difficult Job of Economic Forecasting 524

� CASE STUDY Mistakes in Forecasting 524 Ignorance, Expectations, and the Lucas Critique 526

The Historical Record 527

� CASE STUDY Is the Stabilization of the Economy a Figment of the Data? 528

18-2 Should Policy Be Conducted by Rule or by Discretion? 529 Distrust of Policymakers and the Political Process 529

The Time Inconsistency of Discretionary Policy 530

� CASE STUDY Alexander Hamilton Versus Time Inconsistency 532 Rules for Monetary Policy 532

� CASE STUDY Inflation Targeting: Rule or Constrained Discretion? 533 � CASE STUDY Central-Bank Independence 534

18-3 Conclusion: Making Policy in an Uncertain World 536 Appendix: Time Inconsistency and the Tradeoff Between Inflation and Unemployment 539

Chapter 19 Government Debt and Budget Deficits 543

19-1 The Size of the Government Debt 544 � CASE STUDY The Troubling Long-Term Outlook for Fiscal Policy 547

19-2 Problems in Measurement 548 Measurement Problem 1: Inflation 549

Measurement Problem 2: Capital Assets 549

Measurement Problem 3: Uncounted Liabilities 550

Measurement Problem 4: The Business Cycle 551

Summing Up 551

19-3 The Traditional View of Government Debt 552 � FYI Taxes and Incentives 554

19-4 The Ricardian View of Government Debt 554 The Basic Logic of Ricardian Equivalence 555

Consumers and Future Taxes 556

� CASE STUDY George Bush’s Withholding Experiment 557 � CASE STUDY Why Do Parents Leave Bequests? 559 Making a Choice 559

� FYI Ricardo on Ricardian Equivalence 560

19-5 Other Perspectives on Government Debt 561 Balanced Budgets Versus Optimal Fiscal Policy 561

Fiscal Effects on Monetary Policy 562

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Debt and the Political Process 563

International Dimensions 563

� CASE STUDY The Benefits of Indexed Bonds 564

19-6 Conclusion 565

Chapter 20 The Financial System: Opportunities and Dangers 569

20-1 What Does the Financial System Do? 570 Financing Investment 570

Sharing Risk 571

Dealing With Asymmetric Information 572

Fostering Economic Growth 573

� CASE STUDY Microfinance: Professor Yunus’s Profound Idea 574

20-2 Financial Crises 575 The Anatomy of a Crisis 576

� FYI The TED Spread 578 � CASE STUDY Who Should Be Blamed for the Financial Crisis

of 2008–2009? 580 Policy Responses to a Crisis 581

Policies to Prevent Crises 585

� FYI CoCo Bonds 586 � CASE STUDY The European Sovereign Debt Crisis 587

20-3 Conclusion 588

Epilogue What We Know, What We Don’t 593

The Four Most Important Lessons of Macroeconomics 593 Lesson 1: In the long run, a country’s capacity to produce goods and services

determines the standard of living of its citizens. 594

Lesson 2: In the short run, aggregate demand influences the amount of goods and services that a country produces. 594

Lesson 3: In the long run, the rate of money growth determines the rate of inflation, but it does not affect the rate of unemployment. 595

Lesson 4: In the short run, policymakers who control monetary and fiscal policy face a tradeoff between inflation and unemployment. 595

The Four Most Important Unresolved Questions of Macroeconomics 596 Question 1: How should policymakers try to promote growth in the economy’s

natural level of output? 596

Question 2: Should policymakers try to stabilize the economy? If so, how? 597

Question 3: How costly is inflation, and how costly is reducing inflation? 598

Question 4: How big a problem are government budget deficits? 599

Conclusion 600

Glossary 601

Index 611

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An economist must be “mathematician, historian, statesman, philosopher, in some degree . . . as aloof and incorruptible as an artist, yet sometimes as near the earth as a politician.” So remarked John Maynard Keynes, the great British economist who, as much as anyone, could be called the father of macroeconomics. No single statement summarizes better what it means to be an economist.

As Keynes’s assessment suggests, students who aim to learn economics need to draw on many disparate talents. The job of helping students find and develop these talents falls to instructors and textbook authors. When writing this textbook for intermediate-level courses in macroeconomics, my goal was to make macroeco- nomics understandable, relevant, and (believe it or not) fun. Those of us who have chosen to be professional macroeconomists have done so because we are fasci- nated by the field. More important, we believe that the study of macroeconomics can illuminate much about the world and that the lessons learned, if properly applied, can make the world a better place. I hope this book conveys not only our profession’s accumulated wisdom but also its enthusiasm and sense of purpose.

This Book’s Approach

Macroeconomists share a common body of knowledge, but they do not all have the same perspective on how that knowledge is best taught. Let me begin this new edition by recapping four of my objectives, which together define this book’s approach to the field.

First, I try to offer a balance between short-run and long-run issues in macro- economics. All economists agree that public policies and other events influence the economy over different time horizons. We live in our own short run, but we also live in the long run that our parents bequeathed us. As a result, courses in macroeconomics need to cover both short-run topics, such as the business cycle and stabilization policy, and long-run topics, such as economic growth, the natural rate of unemployment, persistent inflation, and the effects of government debt. Neither time horizon trumps the other.

Second, I integrate the insights of Keynesian and classical theories. Although Keynes’s General Theory provides the foundation for much of our current under- standing of economic fluctuations, it is important to remember that classical economics provides the right answers to many fundamental questions. In this book I incorporate many of the contributions of the classical economists before Keynes and the new classical economists of the past several decades. Substantial coverage is given, for example, to the loanable-funds theory of the interest rate, the quantity theory of money, and the problem of time inconsistency. At the same time, I recognize that many of the ideas of Keynes and the new Keynesians are necessary for understanding economic fluctuations. Substantial coverage is given

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also to the IS –LM model of aggregate demand, the short-run tradeoff between inflation and unemployment, and modern models of business cycle dynamics.

Third, I present macroeconomics using a variety of simple models. Instead of pretending that there is one model that is complete enough to explain all facets of the economy, I encourage students to learn how to use and compare a set of prominent models. This approach has the pedagogical value that each model can be kept relatively simple and presented within one or two chapters. More important, this approach asks students to think like economists, who always keep various models in mind when analyzing economic events or public policies.

Fourth, I emphasize that macroeconomics is an empirical discipline, moti- vated and guided by a wide array of experience. This book contains numerous Case Studies that use macroeconomic theory to shed light on real-world data or events. To highlight the broad applicability of the basic theory, I have drawn the Case Studies both from current issues facing the world’s economies and from dramatic historical episodes. The Case Studies analyze the policies of Alexander Hamilton, Henry Ford, George Bush (both of them!), and Barack Obama. They teach the reader how to apply economic principles to issues from fourteenth- century Europe, the island of Yap, the land of Oz, and today’s newspaper.

What’s New in the Eighth Edition?

Economics instructors are vigilant in keeping their lectures up to date as the economic landscape changes. Textbook authors cannot be less so. This book is therefore updated about every three years. Each revision reflects new events in the economy as well as new research about the best way to understand macro- economic developments.

One significant change in this edition is that some of the existing material has been reorganized. Over the past several years, monetary policymakers at the Federal Reserve have engaged in a variety of unconventional measures to prop up a weak banking system and promote recovery from a deep recession. Understanding these policies requires a strong background in the details of the monetary system. As a result, this edition covers the topic earlier in the book than did previous editions. A complete treatment of the monetary system and the tools of monetary policy can now be found in Chapter 4.

The biggest change in the book, however, is the addition of Chapter 20, “The Financial System: Opportunities and Dangers.” Over the past several years, in the aftermath of the financial crisis and economic downturn of 2008 and 2009, econ- omists have developed a renewed appreciation of the crucial linkages between the financial system and the broader economy. Chapter 20 gives students a deeper look at this topic. It begins by discussing the functions of the financial system. It then discusses the causes and effects of financial crises, as well as the government policies that aim to deal with crises and to prevent future ones.

All the other chapters in the book have been updated to incorporate the latest data and recent events. Here are some of the noteworthy additions:

� Chapter 2 has a new Case Study on the Billion Prices Project, which uses data found on the internet to monitor inflation trends.

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� Chapter 3 has a new FYI box on the growing gap between rich and poor.

� Chapter 4 has a new Case Study on quantitative easing and the recent explosion in the monetary base.

� Chapter 7 has a new Case Study on the recent increase in long-term unemployment and the debate over unemployment insurance.

� Chapter 9 has a new Case Study about industrial policy in practice.

� Chapter 16 has a new Case Study about new research that studies the tax rebates of 2008.

As always, all the changes that I made, and the many others that I considered, were evaluated keeping in mind the benefits of brevity. From my own experience as a student, I know that long books are less likely to be read. My goal in this book is to offer the clearest, most up-to-date, most accessible course in macro- economics in the fewest words possible.

The Arrangement of Topics

My strategy for teaching macroeconomics is first to examine the long run when prices are flexible and then to examine the short run when prices are sticky. This approach has several advantages. First, because the classical dichotomy per- mits the separation of real and monetary issues, the long-run material is easier for students to understand. Second, when students begin studying short-run fluctuations, they understand fully the long-run equilibrium around which the economy is fluctuating. Third, beginning with market-clearing models makes clearer the link between macroeconomics and microeconomics. Fourth, students learn first the material that is less controversial among macroeconomists. For all these reasons, the strategy of beginning with long-run classical models simplifies the teaching of macroeconomics.

Let’s now move from strategy to tactics. What follows is a whirlwind tour of the book.

Part One, Introduction

The introductory material in Part One is brief so that students can get to the core topics quickly. Chapter l discusses the broad questions that mac- roeconomists address and the economist’s approach of building models to explain the world. Chapter 2 introduces the key data of macroeconomics, emphasizing gross domestic product, the consumer price index, and the unemployment rate.

Part Two, Classical Theory: The Economy in the Long Run

Part Two examines the long run over which prices are flexible. Chapter 3 pres- ents the basic classical model of national income. In this model, the factors of production and the production technology determine the level of income, and the marginal products of the factors determine its distribution to households. In addition, the model shows how fiscal policy influences the allocation of the

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economy’s resources among consumption, investment, and government pur- chases, and it highlights how the real interest rate equilibrates the supply and demand for goods and services.

Money and the price level are introduced next. Chapter 4 examines the mon- etary system and the tools of monetary policy. Chapter 5 begins the discussion of the effects of monetary policy. Because prices are assumed to be fully flexible, the chapter presents the prominent ideas of classical monetary theory: the quantity theory of money, the inflation tax, the Fisher effect, the social costs of inflation, and the causes and costs of hyperinflation.

The study of open-economy macroeconomics begins in Chapter 6. Maintaining the assumption of full employment, this chapter presents models to explain the trade balance and the exchange rate. Various policy issues are addressed: the relationship between the budget deficit and the trade deficit, the macroeconomic impact of protectionist trade policies, and the effect of monetary policy on the value of a currency in the market for foreign exchange.

Chapter 7 relaxes the assumption of full employment by discussing the dynamics of the labor market and the natural rate of unemployment. It examines various causes of unemployment, including job search, minimum-wage laws, union power, and efficiency wages. It also presents some important facts about patterns of unemployment.

Part Three, Growth Theory: The Economy in the Very Long Run

Part Three makes the classical analysis of the economy dynamic by developing the tools of modern growth theory. Chapter 8 introduces the Solow growth model as a description of how the economy evolves over time. This chapter emphasizes the roles of capital accumulation and population growth. Chapter 9 then adds technological progress to the Solow model. It uses the model to discuss growth experiences around the world as well as public policies that influence the level and growth of the standard of living. Finally, Chapter 9 introduces students to the modern theories of endogenous growth.

Part Four, Business Cycle Theory: The Economy in the Short Run

Part Four examines the short run when prices are sticky. It begins in Chapter 10 by examining some of the key facts that describe short-run fluctuations in eco- nomic activity. The chapter then introduces the model of aggregate supply and aggregate demand as well as the role of stabilization policy. Subsequent chapters refine the ideas introduced in this chapter.

Chapters 11 and 12 look more closely at aggregate demand. Chapter 11 pres- ents the Keynesian cross and the theory of liquidity preference and uses these models as building blocks for developing the IS –LM model. Chapter 12 uses the IS –LM model to explain economic fluctuations and the aggregate demand curve. It concludes with an extended case study of the Great Depression.

The study of short-run fluctuations continues in Chapter 13, which focuses on aggregate demand in an open economy. This chapter presents the Mundell– Fleming model and shows how monetary and fiscal policies affect the economy

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under floating and fixed exchange-rate systems. It also discusses the debate over whether exchange rates should be floating or fixed.

Chapter 14 looks more closely at aggregate supply. It examines various approaches to explaining the short-run aggregate supply curve and discusses the short-run tradeoff between inflation and unemployment.

Part Five, Topics in Macroeconomic Theory

After developing basic theories to explain the economy in the long run and in the short run, the book turns to several topics that refine our understanding of the economy. Part Five focuses on theoretical topics, while Part Six focuses on policy topics. These chapters are written to be used flexibly, so instructors can pick and choose which topics to cover. Some of these chapters can also be cov- ered earlier in the course, depending on the instructor’s preferences.

Chapter 15 develops a dynamic model of aggregate demand and aggregate sup- ply. It builds on ideas that students have already encountered and uses those ideas as stepping-stones to take the student close to the frontier of knowledge concerning short-run economic fluctuations. The model presented here is a simplified version of modern dynamic, stochastic, general equilibrium (DSGE) models.

The next two chapters analyze more fully some of the microeconomic deci- sions behind macroeconomic phenomena. Chapter 16 presents the various theories of consumer behavior, including the Keynesian consumption func- tion, Fisher’s model of intertemporal choice, Modigliani’s life-cycle hypothesis, Friedman’s permanent-income hypothesis, Hall’s random-walk hypothesis, and Laibson’s model of instant gratification. Chapter 17 examines the theory behind the investment function.

Part Six, Topics in Macroeconomic Policy

Once the student has solid command of standard macroeconomic models, the book uses these models as the foundation for discussing some of the key debates over economic policy. Chapter 18 considers the debate over how policymakers should respond to short-run economic fluctuations. It emphasizes two broad questions: Should monetary and fiscal policy be active or passive? Should policy be conducted by rule or by discretion? The chapter presents arguments on both sides of these questions.

Chapter 19 focuses on the various debates over government debt and budget deficits. It gives a broad picture about the magnitude of government indebted- ness, discusses why measuring budget deficits is not always straightforward, recaps the traditional view of the effects of government debt, presents Ricardian equiva- lence as an alternative view, and discusses various other perspectives on govern- ment debt. As in the previous chapter, students are not handed conclusions but are given the tools to evaluate the alternative viewpoints on their own.

Chapter 20 discusses the financial system and its linkages to the overall economy. It begins by examining what the financial system does: financing investment, sharing risk, dealing with asymmetric information, and foster- ing economic growth. It then discusses the causes of financial crises, their

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macroeconomic impact, and the policies that might mitigate their effects and reduce their likelihood.

Epilogue

The book ends with a brief epilogue that reviews the broad lessons about which most macroeconomists agree and discusses some of the most important open questions. Regardless of which chapters an instructor chooses to cover, this capstone chapter can be used to remind students how the many models and themes of macroeconomics relate to one another. Here and throughout the book, I emphasize that despite the disagreements among macroeconomists, there is much that we know about how the economy works.

Alternative Routes Through the Text

Although I have organized the material in the way that I prefer to teach intermediate-level macroeconomics, I understand that other instructors have different preferences. I tried to keep this in mind as I wrote the book so that it would offer a degree of flexibility. Here are a few ways that instructors might consider rearranging the material:

� Some instructors are eager to cover short-run economic fluctuations. For such a course, I recommend covering Chapters 1 through 5 so stu- dents are grounded in the basics of classical theory and then jumping to Chapters 10, 11, 12, 14, and 15 to cover the model of aggregate demand and aggregate supply.

� Some instructors are eager to cover long-run economic growth. These instructors can cover Chapters 8 and 9 immediately after Chapter 3.

� An instructor who wants to defer (or even skip) open-economy macro- economics can put off Chapters 6 and 13 without loss of continuity.

� An instructor who wants to emphasize economic policy can skip Chapters 8, 9, 15, 16, and 17 in order to get to Chapters 18, 19, and 20 more quickly.

Experience with previous editions suggests this text complements well a variety of approaches to the field.

Learning Tools

I am pleased that students have found the previous editions of this book user- friendly. I have tried to make this eighth edition even more so.

Case Studies

Economics comes to life when it is applied to understanding actual events. Therefore, the numerous Case Studies (many new or revised in this edition) are an important learning tool, integrated closely with the theoretical material presented in each

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chapter. The frequency with which these Case Studies occur ensures that a student does not have to grapple with an overdose of theory before seeing the theory applied. Students report that the Case Studies are their favorite part of the book.

FYI Boxes

These boxes present ancillary material “for your information.” I use these boxes to clarify difficult concepts, to provide additional information about the tools of economics, and to show how economics relates to our daily lives. Several are new or revised in this edition.

Graphs

Understanding graphical analysis is a key part of learning macroeconomics, and I have worked hard to make the figures easy to follow. I often use comment boxes within figures that describe briefly and draw attention to the important points that the figures illustrate. They should help students both learn and review the material.

Mathematical Notes

I use occasional mathematical footnotes to keep more difficult material out of the body of the text. These notes make an argument more rigorous or present a proof of a mathematical result. They can easily be skipped by those students who have not been introduced to the necessary mathematical tools.

Chapter Summaries

Every chapter ends with a brief, nontechnical summary of its major lessons. Students can use the summaries to place the material in perspective and to review for exams.

Key Concepts

Learning the language of a field is a major part of any course. Within the chapter, each key concept is in boldface when it is introduced. At the end of the chapter, the key concepts are listed for review.

Questions for Review

After studying a chapter, students can immediately test their understanding of its basic lessons by answering the Questions for Review.

Problems and Applications

Every chapter includes Problems and Applications designed for homework assignments. Some of these are numerical applications of the theory in the chap- ter. Others encourage the student to go beyond the material in the chapter by addressing new issues that are closely related to the chapter topics.

Chapter Appendices

Several chapters include appendices that offer additional material, sometimes at a higher level of mathematical sophistication. These are designed so that

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instructors can cover certain topics in greater depth if they wish. The appendices can be skipped altogether without loss of continuity.

Glossary

To help students become familiar with the language of macroeconomics, a glossary of more than 250 terms is provided at the back of the book.

Translations The English-language version of this book has been used in dozens of countries. To make the book more accessible for students around the world, editions are (or will soon be) available in 15 other languages: Armenian, Chinese, French, German, Greek, Hungarian, Indonesian, Italian, Japanese, Korean, Portuguese, Romanian, Russian, Spanish, and Ukrainian. In addition, a Canadian adapta- tion coauthored with William Scarth (McMaster University) and a European adaptation coauthored with Mark Taylor (University of Warwick) are available. Instructors who would like information about these versions of the book should contact Worth Publishers.

Acknowledgments

Since I started writing the first edition of this book more than two decades ago, I have benefited from the input of many reviewers and colleagues in the econom- ics profession. Now that the book is in its eighth edition, these individuals are too numerous to list in their entirety. However, I continue to be grateful for their willingness to have given up their scarce time to help me improve the economics and pedagogy of this text. Their advice has made this book a better teaching tool for hundreds of thousands of students around the world.

I would like to mention those instructors whose recent input shaped this new edition:

Mohsen Bahmani- Oskooee University of Wisconsin– Milwaukee

Quentin Duroy Denison University

John W. Graham Rutgers University at Newark

Denise Hazlett Whitman College

Nancy Jianakoplos Colorado State University

Roger Kaufman Smith College

Carlos F. Liard-Muriente Central Connecticut State University

Robert G. Murphy Boston College

Ebere Oriaku Elizabeth City State University

Andrew Paizis New York University

Brian P. Rosario American River College and California State University

Thomas Scheiding University of Wisconsin–Stout

David E. Spencer Brigham Young University

Henry Terrell George Washington University

Bill Yang Georgia Southern University

Nora Underwood University of Central Florida

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In addition, I am grateful to Yang Du, a student at Harvard, who helped me update the data, refine my prose, and proofread the entire book.

The people at Worth Publishers have continued to be congenial and dedicated. I would like to thank Catherine Woods, Senior Vice President, Editorial and Production; Charles Linsmeier, Publisher; Sarah Dorger, Senior Acquisitions Editor; Scott Guile, Executive Marketing Manager; Julie Tompkins, Marketing Assistant; Paul Shensa, Consulting Editor; Tom Acox, Digital Solutions Coordinator; Lukia Kliossis, Associate Media Editor; Mary Melis, Assistant Editor; Lisa Kinne, Associate Managing Editor; Tracey Kuehn, Director of Print and Digital Development, Worth; Barbara Seixas, Production Manager; Kevin Kall, Designer; Karen Osborne, Copy Editor; Edgar Bonilla, Supplements Project Editor; and Stacey Alexander, Supplements Manager.

Many other people made valuable contributions as well. Most important, Jane Tufts, freelance developmental editor, worked her magic on this book once again, confirming that she’s the best in the business. Alexandra Nickerson did a great job preparing the index. Deborah Mankiw, my wife and in-house editor, continued to be the first reader of new material, providing the right mix of criti- cism and encouragement.

Finally, I would like to thank my three children, Catherine, Nicholas, and Peter. They helped immensely with this revision—both by providing a pleas- ant distraction and by reminding me that textbooks are written for the next generation.

Cambridge, Massachusetts May 2012

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Supplements

Worth Publishers has worked closely with Greg Mankiw and a team of talented economics instructors to put together a variety of supplements to aid instructors and students. We have been delighted at the positive feedback we have received on these supplements. Here is a summary of the resources available.

For Instructors

Instructor’s Resources

Robert G. Murphy (Boston College) has revised the impressive resource manual for instructors to appear on the Instructor’s Web site. For each chapter of this book, the manual contains notes to the instructor, a detailed lecture outline, additional Case Studies, and coverage of advanced topics. Instructors can use the manual to prepare their lectures, and they can reproduce whatever pages they choose as handouts for students. Each chapter also contains a Dismal Scientist Activity (www.dismalscientist.com), which challenges students to combine the chapter knowledge with a high-powered business database and analysis service that offers real-time monitoring of the global economy.

Solutions Manual

Nora Underwood (University of Central Florida) has updated the Solutions Manual for all of the Questions for Review and Problems and Applications. The manual also contains the answers to selected questions from the Student Guide and Workbook.

Test Bank

Nancy Jianakoplos (Colorado State University) has updated and revised the Test Bank so that it now includes over 2,500 multiple-choice questions, numerical problems, and short-answer graphical questions to accompany each chapter of the text. The Test Bank is available both as a printed book and on a CD-ROM. The CD includes our flexible test-generating software, which instructors can use to easily write and edit questions as well as create and print tests.

PowerPoint Slides

Ron Cronovich (Carthage College) has revised his PowerPoint presentations of the material in each chapter. They feature animated graphs with careful explana- tions and additional case studies, data, and helpful notes to the instructor. Designed to be customized or used “as is,” they include easy instructions for those who have little experience with PowerPoint. They are available on the Web site (www. worthpublishers.com/mankiw).

supplements and media

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http://www.dismalscientist.com
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For Students

Student Guide and Workbook

Roger Kaufman (Smith College) has revised his superb study guide for students. This guide offers various ways for students to learn the material in the text and assess their understanding.

� Fill-In Questions give students the opportunity to review and check their knowledge of the key terms and concepts in the chapter.

� Multiple-Choice Questions allow students to test themselves on the chapter material.

� Exercises guide students step by step through the various models using graphs and numerical examples.

� Problems ask students to apply the models on their own.

� Questions to Think About require critical thinking as well as economic analysis.

� Data Questions ask students to obtain and learn about readily available economic data.

Online Offerings

FOR MACROECONOMICS www.youreconportal .com

With EconPortal (available Spring 2013) instructors get a complete learning management system, ready to use without hours of prepwork. Students get easy access to learning resources specific to the course and the textbook. And virtually every aspect of EconPortal is customizable.

New to EconPortal � LearningCurve Formative Quizzing Engine bringing adaptive question

selection, personalized study plans, and state-of-the-art question analysis to game-like activities that keep students engaged.

Also Featuring:

� The Eighth Edition Test Bank, with questions sortable by level, skill, for- mat, and topic.

� All end-of-chapter problems easily assignable and automatically gradable.

� Student self-assessment resources tied specifically to the book.

� An HTML-based eBook that allows for note-taking (both public and private), custom syllabi (chapters and sections), highlighting, instructor– student communication, and more! Also available stand-alone as a low- cost text purchase option.

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Companion Web Site for Students and Instructors (www.worthpublishers. com/mankiw)

For each chapter in the textbook, the tools on the companion Web site include the following:

� Self-Tests. Students can test their knowledge of the material in the book by taking multiple-choice tests on any chapter. After the student responds, the program explains the answer and directs the student to specific sections in the book for additional study. Students may also test their knowledge of key terms using the flashcards.

� Web Links. Students can access real-world information via specifically chosen hyperlinks relating to chapter content.

� Sample Essays. Students can view chapter-specific essay questions followed by sample essay answers.

� Data Plotter. Originally created by David Weil, Brown University. Students can explore macroeconomic data with time-series graphs and scatterplots.

� Macro Models. These modules provide simulations of the models presented in the book. Students can change the exogenous variables and see the outcomes in terms of shifting curves and recalculated numerical values of the endogenous variables. Each module contains exercises that instructors can assign as homework.

� A Game for Macroeconomists. Also originally created by David Weil, Brown University, the game allows students to become president of the United States in the year 2017 and to make macroeconomic policy decisions based on news events, economic statistics, and approval ratings. It gives students a sense of the complex interconnections that influence the econ- omy. It is also fun to play.

� Flashcards. Students can test their knowledge of the definitions in the glossary with these virtual flashcards.

Along with the Instructor’s Resources (see p. xxxii), the following additional instructor support material is available:

� PowerPoint Lecture Presentations. These customizable PowerPoint slides, prepared by Ronald Cronovich (Carthage College), are designed to assist instructors with lecture preparation and presentations.

� Images from the Textbook. Instructors have access to a complete set of fig- ures and tables from the textbook in high-res and low-res JPEG formats. The textbook art has been processed for “high-resolution” (150 dpi). These figures and photographs have been especially formatted for maxi- mum readability in large lecture halls and follow standards that were set and tested in a real university auditorium.

� Solutions Manual. Instructors have access to detailed solutions to the Questions for Review and Problems and Applications.

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The Aplia/Worth partnership combines Worth texts and eBooks with Aplia’s interactive problem sets, news analyses, tutorials, and economic experiments—all in a format that saves professors time while encouraging students.

Aplia for Macroeconomics Features: � Homework sets correlated to the text that can be assigned and graded

online. An easy-to-use gradebook tracks results.

� Multiple purchase options. Students can access Aplia free for the first two weeks of the course, then decide if they want to purchase an eBook or a text package. Students purchasing an eBook can also purchase a physical text directly from Aplia at about half off the retail price.

� Algorithmic problem sets. Students can take the tests up to three times with new iterations of the problems each time.

eBook Students who purchase the eBook have access to these interactive features:

� Quick, intuitive navigation

� Customizable note-taking

� Highlighting

� Searchable glossary

With the eBook, instructors can do the following:

� Focus only on the chapters they want to use. Instructors can assign the entire text or a custom version with only the chapters that correspond to their syllabus. Students see the customized version, with selected chapters only.

� Annotate any page of the text. Instructors’ notes can include text, Web links, and even photos and images from the book’s media or other sources. Students can get an eBook annotated just for them, customized for the course.

WebCT The Mankiw WebCT e-pack enables instructors to create a thorough online course or a course Web site. The e-pack contains online materials that facilitate critical thinking and learning, including preprogrammed quizzes and tests that are fully functional in the WebCT environment.

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BlackBoard The Mankiw BlackBoard course cartridge makes it possible to combine Black- Board’s popular tools and easy-to-use interface with the text’s Web content, includ- ing preprogrammed quizzes and tests. The result is an interactive, comprehensive online course that allows for effortless implementation, management, and use. The files are organized and prebuilt to work within the BlackBoard software.

Additional Offerings

i-clicker Developed by a team of University of Illinois physicists, i-clicker is the most flexible and most reliable classroom response system available. It is the only solution created for educators, by educators—with continuous product improve- ments made through direct classroom testing and faculty feedback. No matter their level of technical expertise, instructors will appreciate the i-clicker because the focus remains on teaching, not the technology. To learn more about packaging i-clicker with this textbook, please contact your local sales representative or visit www.iclicker.com.

Dismal Scientist A high-powered business database and analysis service comes to the classroom! Dismal Scientist offers real-time monitoring of the global economy, produced locally by economists and other professionals at Moody’s Economy.com around the world. Dismal Scientist is free when packaged with this text. Please contact your local sales representative or go to www.dismalscientist.com.

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http://www.iclicker.com
http://www.dismalscientist.com
MACROECONOMICS

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P A R T I

Introduction

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3

The Science of Macroeconomics

1C H A P T E R

The whole of science is nothing more than the refi nement of everyday thinking.

—Albert Einstein

When Albert Einstein made the above observation about the nature of science, he was probably referring to physics, chemistry, and other natural sciences. But the statement is equally true when applied to social sciences like economics. As a participant in the economy, and as a citizen in a democracy, you cannot help but think about economic issues as you go about your life or when you enter the voting booth. But if you are like most people, your everyday thinking about economics has probably been casual rather than rigorous (or at least it was before you took your fi rst economics course). The goal of studying economics is to refi ne that thinking. This book aims to help you in that endeavor, focusing on the part of the fi eld called macroeconomics, which studies the forces that infl uence the economy as a whole.

1-1 What Macroeconomists Study

Why have some countries experienced rapid growth in incomes over the past century while others stay mired in poverty? Why do some countries have high rates of infl ation while others maintain stable prices? Why do all countries experience recessions and depressions—recurrent periods of falling incomes and rising unemployment—and how can government policy reduce the frequency and severity of these episodes? Macroeconomics attempts to answer these and many related questions.

To appreciate the importance of macroeconomics, you need only read the newspaper or listen to the news. Every day you can see headlines such as INCOME GROWTH REBOUNDS, FED MOVES TO COMBAT INFLA- TION, or STOCKS FALL AMID RECESSION FEARS. These macroeconomic events may seem abstract, but they touch all of our lives. Business executives forecasting the demand for their products must guess how fast consumers’ incomes will grow. Senior citizens living on fi xed incomes wonder how fast prices will rise. Recent college graduates looking for jobs hope that the economy will boom and that fi rms will be hiring.

Because the state of the economy affects everyone, macroeconomic issues play a central role in national political debates. Voters are aware of how the economy

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4 | P A R T I Introduction

is doing, and they know that government policy can affect the economy in pow- erful ways. As a result, the popularity of an incumbent president often rises when the economy is doing well and falls when it is doing poorly.

Macroeconomic issues are also central to world politics, and the international news is fi lled with macroeconomic questions. Was it a good move for much of Europe to adopt a common currency? Should China maintain a fi xed exchange rate against the U.S. dollar? Why is the United States running large trade defi cits? How can poor nations raise their standards of living? When world leaders meet, these topics are often high on their agenda.

Although the job of making economic policy belongs to world leaders, the job of explaining the workings of the economy as a whole falls to macroeconomists. Toward this end, macroeconomists collect data on incomes, prices, unemployment, and many other variables from different time periods and different countries. They then attempt to formulate general theories to explain these data. Like astronomers studying the evolution of stars or biologists studying the evolution of species, macroeconomists cannot conduct controlled experiments in a laboratory. Instead, they must make use of the data that history gives them. Macroeconomists observe that economies differ across countries and that they change over time. These observations provide both the motivation for developing macroeconomic theories and the data for testing them.

To be sure, macroeconomics is a young and imperfect science. The macroecon- omist’s ability to predict the future course of economic events is no better than the meteorologist’s ability to predict next month’s weather. But, as you will see, macroeconomists know quite a lot about how economies work. This knowledge is useful both for explaining economic events and for formulating economic policy.