1 Comparative Statics and the Paradigm of Economics 1
1.1 Introduction 1
1.2 The Marginalist Paradigm 3
1.3 Theories and Refutable Propositions 9
The Structure of Theories 10
Refutable Propositions 12
1.4 Theories Versus Models;Comparative Statics 14
1.5 Examples of Comparative Statics 16
Problems 23
Selected References 24
Bibliography 24
2 Review of Calculus(One Variable) 25
2.1 Functions,Slopes,and Elasticity 25
2.2 Maxima and Minima 27
2.3 Continuous Compounding 28
2.4 The Mean Value Theorem 31
2.5 Taylor’s Series 32
Applications of Taylor’s Series:Derivation of the First-and Second-Order Conditions for a Maximum;Concavity and Convexity 34
3 Functions of Several Variables 37
3.1 Functions of Several Variables 37
3.2 Level Curves:Ⅰ 37
3.3 Partial Derivatives 39
3.4 The Chain Rule 45
Second Derivatives by the Chain Rule 47
3.5 Level Curves:Ⅱ 49
Convexity of the Level Curves 51
Monotonic Transformations and Diminishing Marginal Utility 53
Problems 55
3.6 Homogeneous Functions and Euler’s Theorem 56
Problems 65
Selected References 65
4 Profit Maximization 66
4.1 Unconstrained Maxima and Minima:First-Order Necessary Conditions 66
4.2 Sufficient Conditions for Maxima and Minima:Two Variables 68 Problems 72
4.3 An Extended Footnote 73
4.4 An Application of Maximizing Behavior:The Profit-Maximizing Firm 74
The Supply Function 81
4.5 Homogeneity of the Demand and Supply Functions;Elasticities 82
Elasticities 83
4.6 The Long Run and the Short Run:An Example of the Le Chatelier Principle 84
A More Fundamental Look at the Le Chatelier Principle 86
Problems 87
4.7 Analysis of Finite Changes:A Digression 91
Appendix 92
Taylor Series for Functions of Several Variables 92
Concavity and the Maximum Conditions 93
Selected References 95
5 Matrices and Determinants 96
5.1 Matrices 96
5.2 Determinants,Cramer’s Rule 98
5.3 The Implicit Function Theorem 105
Problems 109
Appendix 110
Simple Matrix Operations 110
The Rank of a Matrix 112
The Inverse of a Matrix 113
Orthogonality 115
Problems 116
Selected References 116
6 Comparative Statics:The Traditional Methodology 117
6.1 Introduction;Profit Maximization Once More 117
6.2 Generalization to n Variables 121
First-Order Necessary Conditions 121
Second-Order Sufficient Conditions 121
Profit Maximization:n Factors 124
6.3 The Theory of Constrained Maxima and Minima:First-Order Necessary Conditions 128
6.4 Constrained Maximization with More than One Constraint:A Digression 132
6.5 Second-Order Conditions 134
The Geometry of Constrained Maximization 138
6.6 General Methodology 141
Problems 148
Selected References 150
7 The Envelope Theorem and Duality 151
7.1 History of the Problem 151
7.2 The Profit Function 152
7.3 General Comparative Statics Analysis:Unconstrained Models 156
7.4 Models with Constraints 159
Comparative Statics:Primal-Dual Analysis 161
An Important Special Case 165
Interpretation of the Lagrange Multiplier 166
Le Chatelier Effects 169
Problems 172
Bibliography 174
8 The Derivation of Cost Functions 175
8.1 The Cost Function 175
8.2 Marginal Cost 179
8.3 Average Cost 180
8.4 A General Relationship Between Average and Marginal Costs 181
8.5 The Cost Minimization Problem 183
8.6 The Factor Demand Curves 189
Interpretation of the Lagrange Multiplier 189
8.7 Comparative Statics Relations:The Traditional Methodology 193
8.8 Comparative Statics Relations Using Duality Theory 202
Reciprocity Conditions 202
Cost Curves in the Short and Long Run 205
Factor Demands in the Short and Long Run 207
Relation to Profit Maximization 209
8.9 Elasticities;Further Properties of the Factor Demand Curves 211
Homogeneity 212
Output Elasticities 216
8.10 The Average Cost Curve 216
8.11 Analysis of Firms in Long-Run Competitive Equilibrium 218
Analysis of Factor Demands in the Long Run 220
Problems 222
Selected References 224
9 Cost and Production Functions:Special Topics 225
9.1 Homogeneous and Homothetic Production Functions 225
9.2 The Cost Function:Further Properties 228
Homothetic Functions 232
9.3 The Duality of Cost and Production Functions 234
The Importance of Duality 237
9.4 Elasticity of Substitution;the Constant-Elasticity-of-Substitution(CES)Production Function 238
Generalizations to n Factors 248
The Generalized Leontief Cost Function 249
Problems 250
Bibliography 250
10 The Derivation of Consumer Demand Functions 252
10.1 Introductory Remarks:The Behavioral Postulates 252
10.2 Utility Maximization 261
Interpretation of the Lagrange Multiplier 266
Roy’s Identity 268
10.3 The Relationship Between the Utility Maximization Model and the Cost Minimization Model 272
10.4 The Comparative Statics of the Utility Maximization Model;the Traditional Derivation of the Slutsky Equation 276
10.5 The Modern Derivation of the Slutsky Equation 282
Conditional Demands 286
The Addition of a New Commodity 288
10.6 Elasticity Formulas for Money-Income-Held-Constant and Real-Income-Held-Constant Demand Curves 291
The Slutsky Equation in Elasticity Form 291
Compensated Demand Curves 294
10.7 Special Topics 297
Separable Utility Functions 297
The Labor-Leisure Choice 299
Slutsky Versus Hicks Compensations 304
The Division of Labor Is Limited by the Extent of the Market 306
Problems 310
Selected References 313
11 Special Topics in Consumer Theory 314
11.1 Revealed Preference and Exchange 314
11.2 The Strong Axiom of Revealed Preference and Integrability 322
Integrability 325
11.3 The Composite Commodity Theorem 332
Shipping the Good Apples Out 335
11.4 Household Production Functions 341
Comparative Statics 345
11.5 Consumer’s Surplus 347
Example 354
Empirical Approximations 355
11.6 Empirical Estimation and Functional Forms 357
Linear Expenditure System 357
CES Utility Function 359
Indirect Addilog Utility Function 360
Translog Specifications 361
Almost Ideal Demand System 362
Problems 363
References on Theory 366
References on Functional Forms 366
12 Intertemporal Choice 368
12.1 n-Period Utility Maximization 368
Time Preference 371
Fisherian Investment 378
The Fisher Separation Theorem 380
Real Versus Nominal Interest Rates 382
12.2 The Determination of the Interest Rate 384
12.3 Stocks and Flows 387
Problems 391
Selected References 392
13 Behavior Under Uncertainty 394
13.1 Uncertainty and Probability 394
Random Variables and Probability Distributions 395
Mean and Variance 396
13.2 Specification of Preferences 399
State Preference Approach 399
The Expected Utility Hypothesis 400
Cardinal and Ordinal Utility 401
13.3 Risk Aversion 403
Measures of Risk Aversion 405
Mean-Variance Utility Function 406
Gambling,Insurance,and Diversification 409
13.4 Comparative Statics 411
Allocation of Wealth to Risky Assets 411
Output Decisions Under Price Uncertainty 412
Increases in Riskiness 413
Problems 416
Selected References 416
14 Maximization with Inequality and Nonnegativity Constraints 418
14.1 Nonnegativity 418
Functions of Two or More Variables 423
14.2 Inequality Constraints 427
14.3 The Saddle Point Theorem 432
14.4 Nonlinear Programming 437
14.5 An “Adding-Up” Theorem 440
Problems 442
Appendix 443
Bibliography 446
15 Contracts and Incentives 448
15.1 The Organization of Production 448
15.2 Principal-Agent Models 449
Comparative Statics 452
Multitask Agency 454
15.3 Performance Measurement 457
Choosing the Performance Measure 460
15.4 Costly Monitoring and Efficiency Wages 461
15.5 Team Production 463
15.6 Incomplete Contracts 466
Factors Affecting Ownership Structure 469
Problems 471
Selected References 471
16 Markets with Imperfect Information 473
16.1 The Value of Information in Decision Making 473
16.2 Search 474
Sequential Search 476
Equilibrium Price Dispersion 478
16.3 Adverse Selection 482
Favorable Selection 485
16.4 Signaling 487
A More General Analysis 490
16.5 Monopolistic Screening 491
Problems 496
Selected References 497
17 General Equilibrium Ⅰ:Linear Models 498
17.1 Introduction:Fixed-Coefficient Technology 498
17.2 The Linear Activity Analysis Model:A Specific Example 507
17.3 The Rybczynski Theorem 513
17.4 The Stolper-Samuelson Theorem 515
17.5 The Dual Problem 517
17.6 The Simplex Algorithm 526
Mathematical Prerequisites 526
The Simplex Algorithm:Example 530
Problems 534
Bibliography 536
18 General Equilibrium Ⅱ:Nonlinear Models 537
18.1 Tangency Conditions 537
18.2 General Comparative Statics Results 545
18.3 The Factor Price Equalization and Related Theorems 550
The Four-Equation Model 556
The Factor Price Equalization Theorem 558
The Stolper-Samuelson Theorems 559
The Rybczynski Theorem 566
18.4 Applications of the Two-Good,Two-Factor Model 568
18.5 Summary and Conclusions 572
Problems 574
Bibliography 576
19 Welfare Economics 577
19.1 Social Welfare Functions 577
19.2 The Pareto Conditions 581
Pure Exchange 581
Production 584
19.3 The Classical “Theorems” of Welfare Economics 591
19.4 A “Nontheorem” About Taxation 594
19.5 The Theory of the Second Best 595
19.6 Public Goods 597
19.7 Consumer’s Surplus as a Measure of Welfare Gains and Losses 600
19.8 Property Rights and Transactions Costs 604
The Coase Theorem 608
The Theory of Share Tenancy:An Application of the Coase Theorem 611
Problems 615
Bibliography 616
20 Resource Allocation over Time:Optimal Control Theory 617
20.1 The Meaning of Dynamics 617
Brief History 621
20.2 Solution to the Problem 621
The Calculus of Variations 627
Endpoint(Transversality)Conditions 629
Autonomous Problems 630
Sufficient Conditions 632
20.3 Solutions to Differential Equations 633
Simultaneous Differential Equations 636
20.4 Interpretations and Solutions 637
Intertemporal Choice 637
Harvesting a Renewable Resource 640
Capital Utilization 644
Problems 649
Selected References 650
Hints and Answers 652
Index 661