Improving Information for Social Policy Decisions -- Copyright -- Contents -- Contents -- Introduction -- OVERVIEW -- Databases and Methods of Data Enhancement -- Model Design -- Computing Technology -- Model Evaluation -- Model Documentation -- MODELS -- Dynamic Simulation of Income Model 2 (DYNASIM2) -- Household Income and Tax Simulation Model (HITSM) -- Micro Analysis of Transfers to Households (MATH) Model -- Multi-Regional Policy Impact Simulation (MRPIS) Model -- Pension and Retirement Income Simulation Model (PRISM) -- Social Policy Simulation Database/Model (SPSD/M) -- Transfer Income Model 2 (TRIM2) -- REFERENCES -- Databases and Methods of Data Enhancement -- 1 Databases for Microsimulation: A Comparison of the March CPS and SIPP -- INTRODUCTION -- DATA NEEDS FOR MODELING INCOME SUPPORT PROGRAMS -- SURVEY DESIGN OF THE MARCH CPS AND THE SIPP -- SURVEY-BASED PROBLEMS -- Population Coverage -- Household and Individual Nonresponse -- Item Nonresponse -- Reporting Errors -- Sample Size -- Data Delivery -- PROBLEMS OF VARIABLE MISSPECIFICATION -- Income Accounting Period -- Income Detail -- Household Composition Reference Period -- Households and Families Versus Program Filing Units -- DATA OMISSIONS -- Asset Holdings -- Expenditures -- Extended Families -- Other Variables for Related Policy Issues -- EVALUATION OF ESTIMATES OF PROGRAM PARTICIPANTS FROM CPS AND SIPP -- THE DIVISION OF LABOR FOR PRODUCTION OF DATABASES FROM CPS AND SIPP -- THE SUITABILITY OF CPS AND SIPP FOR INTEGRATED MODELING OF TAXES AND TRANSFERS -- CONCLUSIONS -- REFERENCES -- 2 Statistical Matching and Microsimulation Models -- INTRODUCTION -- Definition of Statistical Matching -- File Treatment -- Constrained and Unconstrained Statistical Matching -- Choosing the Matching Variables -- EXAMPLES OF STATISTICAL MATCHES IN MICROSIMULATION MODELS.

The EM-AF Statistical Match -- Merge File of the Office of Tax Analysis -- 1966 Merge File for Household Income Data -- Statistics Canada SCF-FEX Match -- AFDC-Census Match -- STATISTICAL MATCHING: ADVANTAGES AND PROBLEMS -- The Advantages of Statistical Matching -- Problems Associated With Statistical Matching -- Conditional Independence -- Limitations in Modeling -- Error Resulting From the Distance Between X(A) and X(B) -- Reweighting of File B Data Resulting From Statistical Matching -- ALTERNATIVES TO STATISTICAL MATCHING -- Variance-Covariance Analysis -- Iterative Proportional Fitting -- More Data Collection -- Multiple Matching and File Concatenation -- Rough Sensitivity Analysis -- CONCLUDING NOTE -- REFERENCES -- Model Design -- 3 Alternative Model Designs: Program Participation Functions and the Allocation of Annual to Monthly Values in TRIM2, MATH… -- INTRODUCTION -- CONVERTING ANNUAL TO MONTHLY VALUES IN TRIM2, MATH, AND HITSM -- Location of the Annual to Monthly Conversion in the Model Run Stream -- TRIM2 -- MATH -- HITSM -- Determination of Monthly Labor Force and Employment Status -- Input Data -- TRIM2 -- MATH -- HITSM -- Comment -- Determination of Monthly Earnings -- Input Data -- TRIM2 -- MATH -- HITSM -- Comment -- Determination of Monthly Unearned Income -- Input Data -- TRIM2 -- MATH -- HITSM -- Comment -- Evaluation of Alternative Months Procedures -- Need for Further Validation -- PARTICIPATION FUNCTIONS FOR SSI, AFDC, AND FOOD STAMPS IN TRIM2, MATH, AND HITSM -- Supplemental Security Income Participation Functions -- TRIM2 -- MATH -- HITSM -- Comment -- AFDC Participation Functions -- TRIM2 -- MATH -- HITSM -- Comment -- Food Stamp Participation Functions -- TRIM2 -- MATH -- HITSM -- Comment -- Evaluation of Alternative Participation Functions -- APPENDIX: PERFORMANCE OF THE AFDC CALIBRATION PROCESS IN TRIM2 -- REFERENCES.

4 DYNASIM2 and PRISM: Examples of Dynamic Modeling -- THE MODELS -- STARTING DATABASES -- CONTROL TOTALS -- SIMULATION OF LONGITUDINAL HISTORIES -- PRISM LABOR FORCE AND PENSION SIMULATIONS -- Labor Force Simulations -- PRISM Pension Coverage and Characteristics -- Interactions Between Pension and Social Security Eligibility and Retirement in PRISM -- DYNASIM2 LABOR FORCE AND PENSION SIMULATIONS -- Labor Force Simulations -- Retirement in DYNASIM2 -- DYNASIM2 Pension Coverage and Characteristics -- PROGRAM SIMULATIONS -- CONCLUSIONS -- REFERENCES -- Computing Technology -- 5 Future Computing Environments for Microsimulation Modeling -- INTRODUCTION -- Characteristics of Microanalytic Simulation Models -- Layered Structure -- Single Period Versus Future Projections -- Static Versus Dynamic Simulation -- Historical Background -- CURRENT STATIC SOCIOECONOMIC MICRO ANALYTIC SIMULATION MODELS -- Overview -- SPSD/M -- History -- Database Creation -- Database Structure and Size -- Database Adjustment -- Operating Characteristics -- SPSD/M Parameters -- Model Execution -- Comparing Model Runs -- Output Facilities -- Auxiliary Models -- Other Software Facilities -- Operating Environment -- Availability, Customer Base, and Technical Support -- Future Work -- TRIM2 -- History -- Database Creation -- Database Structure and Size -- Database Adjustment -- Operating Characteristics -- TRIM2 Parameters -- Model Execution -- Comparing Model Runs -- Output Facilities -- Auxiliary Models -- Other Software Facilities -- Operating Environment -- Availability, Customer Base, and Technical Support -- Future Work -- Comparison -- Summary -- ANTICIPATED ADVANCES IN COMPUTING AND INFORMATION TECHNOLOGY -- Background -- Informed Industry Observers -- Specific Technical Product Information -- Advances in Computer Processors -- Advances in Primary Memory.

Advances in Secondary Memory -- Advances in Computer Systems Architecture -- Economic Studies of Industry Performance -- Analysis of Industry Information -- Assessment and Predictions -- FUTURE PROSPECTS FOR SOCIOECONOMIC MICROANALYTIC SIMULATION MODELS -- Nature of the Demand for Microanalytic Simulation Models -- Factors Affecting the Availability of Microsimulation Models -- Functions of a System for Microanalytic Simulation -- Larger Model Execution on the Desktop -- Advances in Software Methodology -- Model Specification -- Object-Oriented Computing -- Simulation Module Consistency -- Advantages of Desktop-Based Environments -- Summary -- RECOMMENDATIONS AND CONCLUSIONS -- Short-Term Issues -- Porting TRIM2 to an MS-DOS Environment -- Porting TRIM2 to a UNIX Environment -- Translating TRIM2 Modules to the C Language -- Benefits of Porting TRIM2 -- Medium-Term Issues -- REFERENCES AND BIBLIOGRAPHY -- Model Validation -- 6 Variance Estimation of Microsimulation Models Through Sample Reuse -- COMPUTATIONS OF MICROSIMULATION MODELS -- NONPARAMETRIC VARIANCE ESTIMATION -- MODELS AND VARIABILITY -- BOOTSTRAPPING MICROSIMULATION MODELS -- Incorporation of Sensitivity Analyses-Measurement of Total Uncertainty -- Number of Replications Needed -- Use of Resampling Techniques in Constructing Confidence Intervals -- SUMMARY -- REFERENCES -- 7 Evaluations of Microsimulation Models: Literature Review -- HENDRICKS AND HOLDEN (1976A) -- HENDRICKS AND HOLDEN (1976B) -- GENERAL ACCOUNTING OFFICE (1977) -- HOLDEN (1977) -- HAYES (1982) -- JEFFERSON (1983) -- HAVEMAN AND LACKER (1984) -- ICF, INC. (1987) -- KORMENDI AND MEGUIRE (1988) -- BETSON (1988) -- DOYLE AND TRIPPE (1989) -- BEEBOUT AND HAWORTH (1989) -- BURTLESS (1989) -- DISCUSSION -- REFERENCES -- 8 A Validation Experiment with TRIM2 -- OVERVIEW OF THE EXPERIMENT.

CHOICE OF MODEL YEAR, PROGRAM YEAR, AND COMPARISON VALUES -- CHOICE OF COMPONENT MODULES AND ALTERNATIVES FOR STUDY IN TRIM2 -- OUTPUTS EXAMINED -- ANALYSIS OF RESULTS -- Total Variability Due to Use of Alternative Modules -- Analysis of Variance Methods for Sensitivity Analysis and External Validation -- Nonparametric Analysis -- Analysis of Categorical Data -- MAJOR CONCLUSIONS -- LIMITATIONS OF THE PRESENT STUDY -- DESIGN OF EXPERIMENT ISSUES -- SUMMARY -- REFERENCES -- 9 Evaluating the Accuracy of U.S. Population Projection Models -- INTRODUCTION -- NATURE OF POPULATION PROJECTION MODELS -- VALIDATING POPULATION PROJECTIONS -- Sensitivity Analysis -- External Validation -- CONFIDENCE INTERVALS -- CONCLUSIONS -- REFERENCES -- Model Documentation -- 10 Documentation for Microsimulation Models: A Review of TRIM2, MATH, and HITSM -- INTRODUCTION -- PURPOSES OF DOCUMENTATION AND EVALUATION CRITERIA -- TRIM2 -- Critique -- Suggestions -- MATH -- Critique -- Suggestions -- HITSM -- Critique -- Suggestions -- COMPARISONS WITH IEEE STANDARDS -- REFERENCES.