Research and Analysis by Bernard Wixon

Counting the Disabled: Using Survey Self-Reports to Estimate Medical Eligibility for Social Security's Disability Programs
ORES Working Paper No. 90 (released January 2001)
by Debra Dwyer, Jianting Hu, Denton R. Vaughan, and Bernard Wixon

This paper develops an approach for tracking medical eligibility for the Social Security Administration's (SSA's) disability programs on the basis of self-reports from an ongoing survey. Using a structural model of the disability determination process estimated on a sample of applicants, we make out-of-sample predictions of eligibility for nonbeneficiaries in the general population. This work is based on the 1990 panel of the Survey of Income and Program Participation. We use alternative methods of estimating the number of people who would be found eligible if they applied, considering the effects of sample selection adjustments, sample restrictions, and several methods of estimating eligibility/ineligibility from a set of continuous probabilities. The estimates cover a wide range, suggesting the importance of addressing methodological issues. In terms of classification rates for applicants, our preferred measure outperforms the conventional single variable model based on the "prevented" measure.

Under our preferred estimate, 4.4 million people—2.9 percent of the nonbeneficiary population aged 18–64—would meet SSA's medical criteria for disability. Of that group, about one-third have average earnings above the substantial gainful activity limit. Those we classify as medically eligible are similar to allowed applicants in terms of standard measures of activity limitations.

Early Retirees Under Social Security: Health Status and Economic Resources
ORES Working Paper No. 86 (released August 2000)
by Michael V. Leonesio, Denton R. Vaughan, and Bernard Wixon

Some proposals to change the Social Security program to ensure long-run solvency would reduce or eliminate benefits to some early retirees. To what extent might those benefit reductions cause hardship for individuals with precarious financial circumstances and whose health appears to limit their ability to offset reductions in Social Security income through increased earnings? Our research is intended to identify the size and characteristics of the population that might be at risk as a consequence of such changes.

The central finding is that over 20 percent of early Social Security retirees have health problems that substantially impair their ability to work. In fact, among those aged 62–64 who are severely impaired, there are as many Old-Age and Survivors Insurance beneficiaries as there are beneficiaries under SSA's two disability programs. The retirement program functions as a substantial, albeit unofficial, disability program for this age group. Moreover, the majority of the most severely impaired early retirees would not qualify for Disability Insurance benefits.

Early Retirees Under Social Security: Health Status and Economic Resources
from Social Security Bulletin, Vol. 63 No. 4 (released September 2001)
by Michael V. Leonesio, Denton R. Vaughan, and Bernard Wixon

Policies that would reduce or eliminate Social Security benefits for early retirees could have adverse consequences for older workers in poor health. This article documents the health and financial circumstances of beneficiaries aged 62–64. It examines the extent to which poor health limits work among early retirees and assesses the extent to which curtailment of early retirement benefits might lead to increases in the Disability Insurance program rolls.

Modeling SSA's Sequential Disability Determination Process Using Matched SIPP Data
from Social Security Bulletin, Vol. 58 No. 4 (released October 1995)
by Kajal Lahiri, Denton R. Vaughan, and Bernard Wixon

We model the Social Security Administration's (SSA's) disability determination process using household survey information exact matched to SSA administrative information on disability determinations. Survey information on health, activity limitations, demographic traits, and work are taken from the Survey of Income and Program Participation (SIPP). We estimate a multistage sequential logit model, reflecting the structure of the determination procedure used by State Disability Determination Services agencies. The findings suggest that the explanatory power of particular variables can be appropriately ascertained only if they are introduced at the relevant stage of the determination process. Hence, as might be expected by those familiar with the process, medical variables and activity limitations are major factors in the early stages of the process, while past work, age, and education play roles in later stages. The highly detailed administrative information on outcomes at each stage allows clarification of the roles of particular variables. Planned future work will include policy estimates, such as the number of persons in the general population eligible for the disability programs, as well as analysis of applications behavior in a household context.

Policy Analysis Through Microsimulation: The STATS Model
from Social Security Bulletin, Vol. 50 No. 12 (released December 1987)
by Bernard Wixon, Benjamin Bridges, and David Pattison

Simplifying the Supplemental Security Income Program: Options for Eliminating the Counting of In-kind Support and Maintenance
from Social Security Bulletin, Vol. 68 No. 4 (released March 2009)
by Richard Balkus, James Sears, Susan Wilschke, and Bernard Wixon

The Supplemental Security Income (SSI) program's policies for both living arrangements and in-kind support and maintenance (ISM) are intended to direct program benefits toward persons with the least income and support, but they are considered cumbersome to administer and, in some cases, poorly targeted. Benefit restructuring would simplify the SSI program by replacing ISM-related benefit reductions with benefit reductions for recipients living with another adult. This article presents a microsimulation analysis of two benefit restructuring options, showing that the distributional outcomes under both options are inconsistent with a basic rationale of the SSI program.

Simulating Aggregate and Distributional Effects of Various Plans for Modifying the Retirement Earnings Test
ORES Working Paper No. 46 (released July 1990)
by David Pattison, Benjamin Bridges, Michael V. Leonesio, and Bernard Wixon

Social Security's retirement test continues to receive considerable attention among policymakers. During the past several years a variety of proposals have been advanced that would modify or eliminate the test for persons aged 65–69. In January 1989, we completed a study report, prepared for SSA internal use, that examined several of these proposals, analyzing their effect on earnings, taxes, and benefits in the first year of implementation, assumed to be 1990. The analysis included both aggregate estimates and estimates for selected population subgroups.

Although the specific proposals for modifying the retirement test have changed somewhat during the past 2 years, continued congressional interest has prompted the release of this initial version of our research for public discussion. Because we are in the process of revising the report for final publication, readers are cautioned that numbers and interpretations contained in this paper are subject to change.

A Structural Model of Social Security's Disability Determination Process
ORES Working Paper No. 72 (released August 1997)
by Jianting Hu, Kajal Lahiri, Denton R. Vaughan, and Bernard Wixon

We estimate a multistage sequential logit model reflecting the structure of the disability determination process of the Social Security Administration (SSA), as implemented by state Disability Determination Services (DDS) agencies. The model is estimated using household survey information exactly matched to SSA records on disability adjudications from 1989 to 1993. Information on health, activity limitations, demographic traits, and work is taken from the 1990 Survey of Income and Program Participation. We also use information on occupational characteristics from the Directory of Occupational Titles, DDS workload pressure, and local area economic conditions from unpublished SSA sources. Under the program provisions, different criteria dictate the outcomes at different steps of the determination process. We find that without the multistage structural approach, the effects of many of the important health, disability, and vocational factors are not readily discernible. As a result, the split-sample predictions of overall allowance rates from the sequential model performed considerably better than the conventional approach based on a simple allowed/denied logit regression.

Two Papers on a New SIPP-Based Microsimulation Model of SSI and OASDI
ORES Working Paper No. 54 (released December 1991)
by Bernard Wixon and Denton R. Vaughan

This working paper includes two interrelated papers presented at the annual meeting of the American Statistical Association in August 1991. The papers outline the central ideas and the progress to date associated with the development of a new microsimulation model for program analysis at the Social Security Administration (SSA). The first paper, Rationale for a SIPP-Based Microsimulation Model of SSI and OASDI, relates the analytical potential of the proposed model to data development efforts intended to overcome specific information gaps. It also suggests areas in which the model can enrich SSA's ability to address issues specifically related to either the Supplemental Security Income or Old-Age, Survivors, and Disability Insurance programs or issues requiring comparative analysis of both programs. The second paper, Implementing an SSI Model Using the Survey of Income and Program Participation, describes progress on a preliminary version of the model focusing on the SSI program. It includes a brief description of the model, presentation and discussion of initial results, and comparisons with other studies.